# Liney Halo



## kvom (Aug 11, 2009)

I was inspired by Bogstandard's starting to build this engine, and it looks as if it would be a good (or ambitious) step up from my first two engine builds. For those not familiar with this engine, it's a 5-cylinder radial: http://lineymachine.googlepages.com/l5

Since I still have a bit to finish on the paddleduck engine plus blinging it and Brian's beam engine, I will work on this in fits and starts as time allows. In the meantime, I still need to accumulate tooling that I don't already have.

The first bit is a very thin lathe grooving tool to cut the fins on all the cylinders. The plans are showing .025" grooves, which seems almost paper thin to me. I started by grinding the end of a 3/8" HSS blank on grinding wheel, till I had a width of around .07. The remainder of the forming was done on a manual surface grinder at school. The sides need relief, and I guessed at a 5-degree angle on each side (10 degrees included). To achieve this a sine vise was set at 5 degrees using gauge blocks, and the tool clamped in the vise with the botom side of the tool on the high side of the vise jaws. The left side of the tool must be ground first in order to support the tool with a parallel when grinding the other.

I actually ground it down to .03", but decided to stop as the bottom of the blade was so thin. I think that 5 degrees is too much; 2.5 should be better.

Here's the result:







The grooves in the cylinders aren't critical dimensionally, and aren't deep. We'll see how the tool holds up.

Another necessity for this build is a rotary table, and some of the parts will require that it be mounted vertically. I'd been shopping for a rotab for some time, and found the PhaseII 8" H/V on sale at Enco. Unfortunately they don't honor the free shipping on these tables, and shipping would have raised the price by $75. I called MSC, which has a local presence, and was told that they'd match the Enco price. I picked it up yesterday.

Here's the packing crate, along with a piece of 2" thick 8" diameter aluminum that will be a mounting plate for a 3-jaw chuck eventually. Alongside is a D1-3 backplate that I will use to attach the aluminum to the lathe to cleam up the faces and edges.






Inside the crate:






Once out on the workbench, the only pre-install work to do is to fill it up with spindle oil and clean the table surfaces with mineral spirits to remove the residue from the packing paper. A think coat of oil and it's ready to be mounted.






Eventually I will try to separate the vise and rotab a bit, but I didn't want to take the time to retram the vise. There is no vertical slot for the right side. Instead it must be clamped with this supplied bolt/nut/clamp combo:






There are two other similar clamps for mounting the table vertically.

Here's the first method I decided to try to center the table under the mill spindle. I chucked a conic piece of metal that I use as a bull center on the lathe, and positioned the table so that it fit snugly all around when lowered into the center hole. Then I measured with a DTI, which showed that I was less than .005 out of dead center; good enough for me!


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## ariz (Aug 11, 2009)

wooow kvom, the halo5 that you are going to start is fantastic, surely a step up as you said, but not too ambitious for you, the paddleduck wasn't a joke
however, you have the determination to overcome the difficulties, when they will arrive

and double wooow... the phase II is a good rotary table :bow:, I also wanted to buy one, but it isn't the right moment now
it looks great, and being a 8'' rt, looking how it stays on the table, I think that your mill would not be small: what mill do you have? 


BTW, the tool for the fins on your next engine is very well done, stop there, nobody will measure the fins of your halo5


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## zeeprogrammer (Aug 11, 2009)

Oh this is going to be interesting!


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## kvom (Aug 11, 2009)

The rotab doesn't come with t-slot nuts, and the slots are smaller than the Bridgeport table slots. I measured the slots and did some internet searching. One eBay seller has the size that fits at a price of $22 for 10. I can't see needing 10, so I decided to make some. The width of the slots at table height indicate the need for 7/16" studs. I happen to have a foot or so of 7/16-14 threaded rod, so I went to the local hardware store to purchase the locking nuts. Once back home, I discovered that my tap&die set has a 7/16-20 NF tap but not the NC. Back to the store to purchase a tap. I then spent a good 90 minutes milling the necessary t-nut form in a 6" length of mystery steel (definitely not 12L14, lots of blue chips ;D), then cut off 4 1" pieces.

After dinner I need to drill and tap them. Hoping not to break the tap.


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## kvom (Aug 14, 2009)

After working on the Jeep all afternoon, I still had a little energy for some machining. I haven't decided which chuck to buy for the rotab, so I started to clea up the aluminum mounting plate. The first order of business was to center the lathe backing plate and drill four holes for the 3/8" mounting bolts:






Note that since the disc is 8.25" in diameter, I couldn't clamp it normally in the vise. I reversed the hard jaws on the Kurt to allow clamping it for drilling. Once the holes were through, I pulled out this countersink that I'd gotten along with the mill in order for the bolts heads to be below the surface of the plate. Useful gadget. 






Now I could mount it at the lathe to clean up the face and sides.






Then I flycut the reverse side, hopefully yielding a plate that will keep the enventual chuck square to the rotary table.






The next step will be to cut 4 mounting notches into the side to attach it to the rotab.






In the meantime, I will try to start on one part via the CNC lathe at school: the cam housing. The first screenshot show the simulation of the g-code for drilling and boringL






Assuming that works properly, the piece is turned around in the vise to turn the front profile:






I'll try them out on Monday afternoon.


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## arnoldb (Aug 16, 2009)

Looks like you end up with the same predicament I do - first need to make tools to start on a project 
Nice start on the Halo - looks like a nice one to build!

Regards, Arnold


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## kvom (Aug 16, 2009)

I bought a 6" plain back chuck on eBay last night. It has 2 piece jaws, so even if the runout is too high I can still make soft jaws.

I also found a 8" D1-3 3-jaw chuck with 2-piece jaws on PM. That too will get soft jaws for lathe work.


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## kvom (Aug 18, 2009)

I ran the first half of the cam housing programs on Monday night. Since we have to share the lathe setups, I was limited to using the existing chuck jaws and could add only the boring bar to the tool holder. The existing 3-jaw chuck was set for 2.5" stock, so I needed to adjust the program to turn down from there as opposed to the 2" I had previewed. Since I couldn't drill the stock on the CNC lathe, I needed to cut off 1.5" thick discs of aluminum bar and then drill them 11/32 on the manual lathe.

Using the Haas CNC lathe there is a longish setup process where you touch off the X and Z coordinates for each of the tools your program will use. In this case I was using a turning/facing tool, the boring bar, and the parting tool.

Eventually I was ready to cut, but the first pass is always done by single stepping the program to make sure there are no gross errors that would break a tool or the machine. This took about 15 minutes to make the first piece.

Next I measured the critical dimensions. The boring depth was .008" too shallow as measured by a depth mic; since this is the critical dimension of the part, I needed to adjust an offset for the boring bar to correct for it. The second part was run a bit faster, and then remeasured to confirm the dimension is fixed.

The last two copies were run at full speed, taking 7 minutes machine time for each. One of the pieces received a slight ding, likely by hitting a chuck jaw when parted, so I have two "scrappies" and two good parts.






The second program to form the nose will likely need to wait until next week, as a new set of jaws needs to be bored to chuck the 1.675" diameter. The jawqs on these lathes are hydraulic and have a fairly short range of motion, so they need to be bored to fit a given depth and diameter, similar to soft jaws.

So producing the two good parts has taken approximately 6 hours, including programming, setup, and run time. It's interesting to work on, but obviously inefficient for small quantities.


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## kvom (Aug 19, 2009)

My cheap Chinese 6" plain back chuck arrived today, so I spent the afternoon working to get it mounted on the rotary table. The first order of business was to verify the bolt circle of the 3 mounting holes in the back. I used the DRO to verify that the diameter is 142mm. The holes are threaded M8-1.25, so it was off to the hardweare store to purchase bolts of the correct length. After drilling the holes, I countersunk them with a .5" endmill, but the hole was still a few thou too small. A few minutes with the grinder reduced the heads so that I could attach the chuck to the plate.

With the chuck mounted, there is a 3/4" flange remaining for mounting slots. I milled these with the side flutes of a 1/2" endmill. Here's the result mounted on the rotab:






I removed one of the top jaws for measurement, as I intend to make a set of soft jaws. The next step will be to center the chuck body on the table, and then meaure the runout with the supplied jaws.


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## Bernd (Aug 19, 2009)

Kirk,

Might I suggest some washers under those bolts. Hate to see you ruin that nice aluinum plate. I know there's no room on the one side of the bolt. Grind the edge of the washer down so it'll fit.

Bernd


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## kvom (Aug 20, 2009)

Found some washers that fit unmodified. I don't plan to ever remove the chuck from the plate, but the washers do give the advantage that they clear the bolts from the side of the chuck.

I got the rotab chuck dialed in today, although it took longer than it should have. I was holding the DTI in the spindle, but a better idea would have been to use the mag holder on the table. Indicating on the body of the chuck, I got it to within .001". Next I need to clamp a round bar and indicate to see how concentric the jaws might be.


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## kvom (Aug 25, 2009)

I turned the other side of the cam housings on the Hass lathe last night. It turns out one of my "good" ones was bad, so I have 2 good ones left. Hopefully I can drill all of the necessary hole (20 of them) without screwing up on at least one of the two.






Since I have machine time this week, I'm going to CNC the driveshaft as well. I cut off 4 2.25" pieces of 3/4" 12L14 before leaving. I'll face off at home, and turn them on Thursday if all goes well.


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## kvom (Aug 28, 2009)

I turned the driveshaft on the Haas lathe at school last night. I started with 4 blanks and managed to get only one good part. Since I won't have access to the machine anytime in the near future, this is the last part for this engine I'll be able to make via CNC. However, at least I was able to run the two parts that have the critical dimensions.






I still need to drill and tap 3 holes on the part. I bought a package of 2-56 taps on eBay yesterday, so hopefully I won't fubar this.


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## kvom (Sep 12, 2009)

I have been working on the crankcase over the past few nights as time permitted. I'm sure John will make this a lot differently as he has 6 to do, but here's my effort.

Since I had a precision 1" bore in the rotab chuck's soft jaws, I chucked a piece of 2" dia. aluminum rod in the lathe and turned down one end to 1" diameter. On the other end I turned down 1" in length to the required diameter of 1.65". I then bored the interior to .75" for a depth of 1". I don't have a good boring setup for the lathe as yet, so further boring will be done on the mill.

Having previously dialed the rotab in to work on the cam housing, I was able to chuck the raw crankcase without further ado. I then used an endmill to enlarge the bore to just over 1".






Since all of the holes to be drilled and tapped into the interior will cause burrs, I plan to bore to the final diameter of 1.25" after all the drilling is done. This will remove the burrs, which might be difficult to access otherwise.

Next the mounting holes for the cam housing were drilled.






With the crankcase still in the chuck, I tilted the rotab to the vertical position. Here's my method of squaring it to the mill table:






The mounts for the cylinders were machined next. I used a .75" endmill that was actually only .725", so each flat needed two extra passes to attain the necessary width.






I spot drilled the five holes needed in each flat, then drilled and reamed the center hole to .500".






Next there were 20 mounting holes to be drilled with a #50 drill. I have two of them, but somehow I have lost or misplaced one of them. Since there are a lot of holes this size to be drilled I hope I find the spare.






Given the angles of the mounting holes, I just tapped them 2-56 using the guide I had previously made to tap on the mill or lathe. It turned out to be very easy to tap aluminum with this setup. The weight of the chuck was enough to start the tap cutting, and the taps cut very well. Less than minute for each hole.






Trial fit of some screws:






Unchucked the crankcase and put it on the tapping stand to tap the 5 holes for mounting the cam housing.






The next step will be to bore the interior to final dimension. I will hold off parting off the crankcase as long as possible.


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## zeeprogrammer (Sep 12, 2009)

Wow. That looks really good kvom.


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## joe d (Sep 12, 2009)

Looking good, Kvom!

Please keep up with posting your progress, this one is on my "want to build" list, so a tutorial will come in VERY handy :

Cheers, Joe


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## Maryak (Sep 12, 2009)

kvom,

Lovely job on the crankcase. :bow: :bow:

Best Regards
Bob


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## ariz (Sep 13, 2009)

a very well done work on that crankase kvom :bow:

I'm happy that your tapping stand works well too

keep up on this great built


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## Paolo (Sep 13, 2009)

Great Job... :bow: :bow: :bow:
Paolo


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## kvom (Sep 16, 2009)

Here's the finishing touches on the crankshaft. I drilled the center hole on the lathe, and then mounted in the collet block to drill the two holes in the flange (these holes are used to attach the cams).






Then all three holes are tapped 2-56 at the tapping stand. Once again, the weight of the tap and chuck were enough to start the tap easily in the steel (12L14).


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## kvom (Sep 17, 2009)

I recently bought some 1-1/4" brass round via eBay for the cylinders, and since they arrived I decided to make the first one to see if my imagined machining sequence would work. It's a bit different from John's, but doesn't require any jigs.

The first step is to turn the basic shape. First turn the 3/4" upper section, then drill and ream the bore, and part off at 1" of length. I then reversed the piece in the chuck and faced the cut end. After measuring, I rechucked on the 3/4" section and turned the bottom to 1/2" diameter leaving .100" for the flange. That completes the lathe work for now.







I chucked the 3/4" end in a 5C collet block, mounted the block horizontally in the mill vise, and milled the flange to 3/4" square.






Next I mounted collet block vertically, located the center, and drilled the 4 mounting holes in the corners.






A quick test fit onto the crankcase:






Finally I reversed the piece in the collet block using a 1/2" collet, squared the flanges to the block using my height gauge, and drilled the mounting holes for the head.






Given that I have too many balls in the air project-wise, I probably won't make the other 4 anytime soon. In any case, I still need to tap the holes on the top, and cut the fins. I will definitely be following John's process for setting up the parting tool in the lathe for that. Once the fins are cut, the only remaining worj will be to shorten the 1/2" spigot to .100"; it's made ~2.5" initially to give more surface for chucking in the collet and lathe.


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## kvom (Sep 28, 2009)

Today I finished roughing out the other 4 cylinders. They all need the same finishing: tap the holes where the head mounts, cut the fins, and trim the bottom spigots to length. In the meantime, a poser shot to test fit on the crankcase:


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## Cedge (Sep 28, 2009)

Kvom
You're looking darned good so far. I'm quietly watching your progress and planning for the time when I take on one of these little engines, so keep it going!!

Steve


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## zeeprogrammer (Sep 29, 2009)

Looking pretty real kvom.
You've got two very nice projects going (i.e. the Paddleducks too).


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## CrewCab (Sep 29, 2009)

Kirk,

I seem to remember about 12 months or so back you were just gonna just "lurk" till you had a bit more experience, well ....... your lurking days are certainly over ................. excellent work mate :bow:

Very well done ;D

CC


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## Krown Kustoms (Sep 29, 2009)

Very nice,
that is going to be nice
-B-


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## kvom (Sep 30, 2009)

Made a few more parts fpr the engine. First up was the crank and crank pin. I turned the crank from a piece of 1" 12L14. Faced the end of the rod, then turned .25" down to the .75" required diameter, and finally drilled the clearance hole (#43 drill .25" deep). The face needs to be countersunk to accept the flat screw. I should have used a screw to test the depth, but eyeballed it instead. I will need to deepen it so that it sits flush, else the conrods will hit the protruding screw.  

Before parting it off, I took the rod off the lathe, mounted it in a 5C collet and collet block, and used the mill to drill the offset hole for the crank pin. This was actually unnecessary as I had to mill the reverse side after parting off, and I could have drilled the hole then. Once I had milled the reverse to achieve the required disc thickness, I needed to counterbore the center hole 3/16" diameter and .04" deep to match the crankshaft.

The crank pin was made from 3/8" drill rod. Here are the two parts:






and assembled onto the crankshaft:






Next up was finish boring the crankcase to 1.28". The interior finish isn't very good (using a brazed carbide boring bar). I think HSS would have been better. The holes make for an interrupted cut. I'm thinking now that drilling these after boring would be preferable, as with the thinner walls it's possible to debur the inner edges from the outside.






Test fit with the cam housing:






Final work for the day was to turn the push rods from .25" brass rod. This was not a difficult job, but was rather tedious as I need 10 of them. Each took ~10 minutes and three adjustments of the toolpost. First face the end, then turn to .125" diameter for a length of .465", and finally part off to .500". Once I had the 10 blanks, I mounted the shafts in a smaller collet and used a form tool to round off the heads, as shown in the plans. Had I not had the form tool, I could have also used my 1/8" corner rounding endmill mounted in a toolholder.


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## cobra428 (Sep 30, 2009)

kvom 
Nice work Thm:
Tony


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## itowbig (Sep 30, 2009)

ya man nice work im watching and wishing i could get this good.


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## woodchip85 (Sep 30, 2009)

Looking good kvom, Thm: lovely job. After watching you and bogstandard build this engine i wanted to have ago a building a radial 5 cylinder, but to my own design. Any ways to cut the story short i hit a few design problems :wall: when it came to the valves and timing, so i bought a set of plans for the linley halo and wow am i happy. 

Ill be watching your progress until i have time to start mine.


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## kvom (Sep 30, 2009)

Thanks for the support.

I hope to see your progress soon too, woodchip.  

Since I don't have any brass the correct size for the heads, I'm planning to make the heads from aluminum and the valve cover from brass, just reversing the materials in the plans. Today I started on one of the heads. There is a lot of milling and drilling to do on a fairly small block of metal, but after a lot of studying the 3 separate drawings of the head I think I have it figured out. I did everything but drill and ream the holes for the pushrods, plus I need to acquire a 1/16" endmill to make the slot for the inlet. Pictures to come later. I spent about 5 hours getting to this point; for the remainder, using a vise stop to perform the same ops on all will save a lot of time. I still think it will take ~2 hours each.


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## kvom (Oct 1, 2009)

Last night and today I made the first head. I still need a 1/16" endmill to finish a couple of minor operations, plus a 1/8" reamer, but this is it in essence:






As can be seen, lots of holes to drill in 4 of six sides. On the top are 7 holes: 4 through hols for mounting to the cylinder, one tapped hole in the center for attaching the rocker bracket, and the two holes on the little "plastforms" for the pushrods.

On "front" you can see 9 holes: 6 for attaching the valve cover, two holes for the valves, and one hole giving access to the cylinder. I still need to connect this hole to the right valve hole with an air passage, hence the need for the small endmill.

The bottom side has two holes that open to the cylinder. On the left it opens very slightly to the rear of the left (input) valve hole. On the right it joins with the small hole in the front.

The right side, a small exhaust hole joints to the right valve hole.

I didn't understand how the valves worked until I had made the head and understood the interconnections of the air passages. While the plans seem accurate, there is very little in the way of explanations or assembly instructions. The valving works as follows:

1) The two valve holes are counter bored and will contain a ball bearing that is larger than the inner part of the bore. When the pushrod for a hole is raised, the ball seals that hole, blocking any air passage. The left hole is the input side. The air inlet in the valve cover opens to this hole. When the pushrod descends (pushed by the rocker arm), it pushes the ball outward permitting air to enter the cylinder bore.

2) Conversely, the right ball valve prevents are from leaving the cylinder until its pushrod descends. Then the piston's upward motion pushed air through the right bottom hole, into the lateral hole, through the small air passage, into the right valve hole, past the valve ball, and out the exhaust hole.

Obviously the rocker arms must be out of phase by 180 degrees so that one valve is shut while the other is open.

The valve cover was made next. I started with a 1/4" piece of brass plate, but mistakenly milled it to 1/8" thickness before milling the countersinks for the mounting screws. I don't have a set of parallels that will allow me to hold it securely to mill these now, so I will likely throw this one out and make 5 more. In any case, here's how the head looks with the cover attached:






The hole in the left center is the inlet.

I then made a rocker arm bracket, but I'm not very happy with it either. The top can be optionally rounded over with a file or corner rounding bit, but I made it slightly too thin so that the cross hole is not centered. Once again I think it's a throwaway. In any case, this shows how it mounts to the head:


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## woodchip85 (Oct 2, 2009)

Looking even better kvom, sorry to hear about the mishaps. 

Has anyone any idea about problems that could occur if i scaled the plans of this engine up. I think id struggle with some of the smaller parts with the machines and tooling i have to hand.


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## Krown Kustoms (Oct 2, 2009)

Not sure of any problems, but you would probably need a bigger airplane. :big:
-B-


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## kvom (Oct 2, 2009)

For my money the biggest issue in scaling up would be determining what fasteners to use. If you build to plan you can buy a fastener kit from Liney that has the needed 2-56 screws, nuts, washers, as well as steel balls, 2 bearings, springs, and some pins. Most of the 2-56 screws are SHCS, but there are a few flat heads. Obviously the two bearings would have to be obtained to match the crankshaft, and then the cam housing dimensions might need to be refigured to match whatever bearings are to be used.

That said, I have not been finding the size of the parts very difficult to manage. One challenge is milling the fins on the cylinders, but there are optional, or can be made wider than plan. As said before, all screws are 2-56, and so you mainly need the tap and body drills for this size. Tapping in brass, Al, and steel with these taps has been much easier than 5-40 or larger. Almost all the other needed drills holes are 1/8" (you do need over/under reamers for this size).


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## Krown Kustoms (Oct 2, 2009)

By the way
If I havent said it yet, the build looks great KVOM.
I look foreward to seeing more.
-B-


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## Cedge (Oct 2, 2009)

Kvom
Tapping 2-56 will either teach one patience and humility or it will turn you into a raving consumer of cheap rot gut.... *beer* . It isn't that bad once you have a feel for the tension on the tap, but I've broken my share of them, especially in aluminum.

I've learned that I sometimes prefer to make a first run part, knowing it is destined for the scrap bin. Often I'll even make it from cheaper materials. I get the mistakes out of the way early on and then the rest of the parts go off with a lot fewer problems. 

I looked at the plans for this engine today and you're right..... The designer was quite generous with all he holes in those head assemblies. All I can say from here is that you are doing yeoman's duty with the tiny things. I do believe that you've even got George looking at it all with a sense of awe.

Steve


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## kvom (Oct 4, 2009)

Yesterday and this morning I had high hopes of finishing 5 cylinder heads. I had milled the profiles, spot drilled all 18 holes on each, and had drilled the 4 though mounting holes on each as well. The first task this morning was drilling the 2 valve holes. The plans call for a 5/32 drill, but mine is missing so I decided to use the nearest number drill (#23). This hole is drilled to a depth of .400", and then a #8 (.200 nominal) is used as a counter bore. Unfortunately, when i did the first hole with the #8, there was no swarf.  After some investigation, I found that the tip of the #23 had broken off halfway, and somehow this resulted in oversize holes. Effectively, all 5 heads were now ruined. I was not a happy camper, although I had managed to refine the machining process so that I had wasted only 3-4 hours on all 5 rather than the 3-4 hours I spent making the first one solo.  

The other sad thing is that I had two #23 drills; the good one wa sitting in the space 5/32 in the drill index, and had I used that one all would be well.

Rather than restart the heads immediately, I decided to work on the valve covers. A couple of hours work resulted in a satisfactory result:






Nothing too difficult in machining these, given a vise stop and a DRO.


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## zeeprogrammer (Oct 5, 2009)

I wish I could loan you an anvil...but I haven't got one! :big:

Seriously though, sorry about the heads.
Nice looking valves!


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## kvom (Oct 6, 2009)

I was thinking of something other than a little hole for the exhaust, but it will be an "add-on" once the engine runs. As for a rigid manifold, I suspect I could still use these flanges as long as the input pipe fits the 6-32 threads. That too would be an add-on.

Yesterday I started making the rocker brackets, and today I drilled the holes. I'm still waiting for my set of O/U reamers to arrive; when they do I can ream the cross hole .124".






I also finished the milling part of a set of new heads, but didn't feel up to the marathon of drilling they need, so I set them aside for another day.

Then started on the bearing carrier. I had a piece of aluminum that just needed a bit of turning on the lathe to arrive at this:






The left side is turned to 1" diameter so that it would chuck accurately in the soft jaws on the rotab. The right end was faced; it's diameter is about .200" larger than the final diameter of the carrier. Then I invoked Marv Klotz's flywheel program to get parameters for milling the spokes. Everything is drilled/milled .150" deep or more:






Once I obtain the 3/8" under reamer for the center hole, I will turn the outer diameter on the lathe and part off the carrier at the specified .125" thickness. I did countersink the mounting holes after the picture was taken as they use flat head screws.


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## Brian Rupnow (Oct 8, 2009)

Kvom---I haven't said anything before now on this thread, but I want you to know how impressed I am with your work. You are going places with this build that I am quite sure are beyond my capabilities. Best of luck, and yes, I watch your builds as well.----Brian


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## kvom (Oct 8, 2009)

Thanks Brian. I'm enjoying this one. Your radial will be done long before mine.


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## kvom (Oct 9, 2009)

Made the cams:







I turned some brass rod down to .780" and drilled the center hole, then mounted it in the rotary table to mill the rest of the profile and drill the mounting holes. Then it was back to the lathe to part off two "slices". Finally I milled the cams to the desired thickness.

Here they are mounted on the driveshaft:






The dimensions given result in a very precise, tight fit. To get the screws to line up with the taped holes in the shaft I needed to file the center hole slightly to give some wiggle room. I also think a #43 drill for the mounting holes would be preferable to the #44.

One issue to resolve at assembly time is the angle the crank pin needs relative to the cam lobes. The cam nearest the end drives the input valve, so I'm guessing that the valve should start to open somewhat just before TDC. Comments?


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## Deanofid (Oct 10, 2009)

I'm enjoying watching your progress on this, Kvom. Sorry to hear you have to remake the heads!
This is an impressive looking engine when finished, and I was pretty smitten with it the first time I heard it run in a video. It sure sounded good, to go along with it's good looks. I'm rooting for your success!

The prints look pretty good from what I see in your pictures here, but seem to use unconventional dimensioning. 
In your picture of the cams, what does the call-out of 11 degrees refer to? The end of the .680" dia? It almost looks like it's referencing the outer dia of the #44 hole. Just curious about that.

Thanks for the write up here.

Dean


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## kvom (Oct 10, 2009)

I think the 11-degree is an error. Since the flats are milled at 10 degrees from the centerline, 11 ought to be 10 as well. In any case it's unnecessary.

WRT dimensioning, Liney states that some dimensions are left off to keep the drawings uncluttered. Sometimes you need to look at the drawings for another part to find a dimension. So far I haven't had any difficulties in that respect.


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## Deanofid (Oct 10, 2009)

kvom  said:
			
		

> WRT dimensioning, Liney states that some dimensions are left off to keep the drawings uncluttered. Sometimes you need to look at the drawings for another part to find a dimension. So far I haven't had any difficulties in that respect.



I was thinking about his use of extension lines and the practice of using "dia" in place of "R" for incomplete circle lines. I don't mean to imply there's anything wrong with the prints. Was just something I noticed.
Thanks,

Dean


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## kvom (Oct 13, 2009)

After a weekend spent mostly watching the Presidents Cup golf matches on TV and some assorted honey-dos, I spent the afternoon in the shop making a little progress.

The first order of business was to get the bearing retainer finished. Since I now had a 3/8 under reamer, I mounted the piece in the lathe and reamed the center hole to .374. Then I parted off the part and spend some time cleaning up the mounting holes; the tapping stand was useful for this. Then there was the obligatory trial fit:






Looks as if I need a deeper countersink for the screws, and some filing to make the spokes a bit nicer. I did a quick test of the bearing supplied by Liney, and it looks as if it will be a nice fit - not loose but not terribly tight either.

Not being overly ambitious, I decided to just make the rocker pins. Although these are pretty darn simple, they were tedious to make with lots of ins and outs on the collet chuck. First, hacksaw off 5 pieces of 1/8" brass rod a bit longer than the finish length; next face all 10 ends to get accurate length measurement. Then face off to final length. Now I needed to center drill each end, as I was not sure that I would get a straight hole drilling through from one end. So I drilled halfway, then turned around and drilled through from the other side. The final operation was threading each end, using the bushing I made to fit the tapping chuck. So I probably spent two hours just to make these 5 small, simple parts.


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## Deanofid (Oct 13, 2009)

Sometimes small "simple" parts seem to take the most time, but it's pretty neat when you make a bunch up and they all fit! Enjoying your build.

Dean


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## kvom (Oct 16, 2009)

More shop time making little fiddly parts the past few days.

Since I obtained my O/U reamers, I reamed the cross hole of the rocker bracket and inserted the rocker pins. Not a press fit, but I suppose brass rod isn't necessarily on size.






Next I started on the rocker arms. I first took a 6x6" piece of 1/4" aluminum plate and cut off as slice that I machined to 1" wide. I then milled the profile of the arms. The sides of the center section were milled with a 1/8" ballend endmill to obtain the rounded corner profile. I then used a 1/4" endmill to slice off 10 pieces. At the end of the cut the pieces would snap off leaving a large burr that would need to be milled off later.






The next machining steps required the use of soft jaws on my Kurt vise, as both the rockers and the connecting rods to follow are 1/8" thick. After mounting the jaws, I milled off the existing slot with a 1/8" endmill to get a flat starting point. Then I clamped a 6" rule between the jaws to allow clamping room later, located the center of the slot with the edge finder, and milled a 3/32" deep slot with a 1/8" endmill.






After positioning a vise stop and locating the x-axis with the edge finder, I was able to mill off the burr from each piece, and then drill the vertical hole that will accept the pushrod:






The same setup was used to spot drill, drill, and ream the cross hole for the rocker pin.






Finally, I cut four pieces of 1/8" square brass rod (using a wire cutter is quicker than hacksawing), and used the same vise slots to mill to length, drill the cross holes, and finally mill the slot in the end (1/16" endmill):






For those who haven't tried soft jaws and have a vise with removable hard jaws, I can recommend them for holding thin pieces where parallels are impractical. Note that you can drill into the jaws through the pieces, which is not a good idea with hard jaws.


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## zeeprogrammer (Oct 16, 2009)

You weren't kidding when you said 'fiddly parts'. Wow. Nice job.


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## ariz (Oct 17, 2009)

I see that you do manage these serial pieces in a neat way

very efficient and very well done!


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## kvom (Oct 18, 2009)

Yesterday and today I worked on the most challenging part thus far, the master rod. Because of the irregular shape I figured I needed a jig to hold it. First I reduced a small piece of 1/4" brass to .375" wide by 1.25" long and drilled the holes needed for the wrist and crank pins. After reaming the crank pin hole, I machined it to 1/16" thickness.

For the jig, I found a 3" diameter disc of aluminum about 3/4" thick. I turned one side for a 1" diameter spigot that would mount on the rotab, and then turned the other side with a small .125" spigot that would be a tight fit for the crank pin hole. Once mounted on the rotab and centered under the spindle, I set the rotab to 0 degrees and drilled a .063" hole .850" from the center. I then could mount the workpiece on the center spigot and hold it laterally with a piece of 1/16" drill rod. I then drilled the 4 holes to which the other connecting rods will be pinned:






Next using a 1/8" endmill I tried to carefully machine the profile using a combination of linear and rotary motions. Unfortunately it seems I had a slight undercut on one side.






I trimmed the tail to length leaving a workable, although less than perfect, master rod.






Some lessons I learned. I had intended to drill and tap a hole in the tail as a hold-down (for that reason it was left long). When I first mounted it on the jig it was very solid, so I neglected that step. On a do-over I would do so as the piece did have a tendancy to lift when milling the tail portion. Rather than the spigot in the center of the jig, I would just drill a hole and insert some 1/8" drill rod.


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## zeeprogrammer (Oct 18, 2009)

Nice kvom. I'm going through a similar process on my reversing lever. It is very much a learning experience.


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## kvom (Oct 18, 2009)

Since my house was invaded this afternoon by 7-8 teenagers at the invitation of my daughters, I decided to hide out in the shop. It was finally time to turn the fins in the cylinders, as they had been waiting since 9/28 to be finished up. Bogstandard has a fine writeup on setting up the very thin parting tool (.025", no relief), and I followed it pretty much as written. Since the tool needed a surface grinder to create, others attempting this build might choose to use a wider, commercial tool and cut fewer fins (or no fins at all). I was able to chuck the parts in my Jacobs Rubberflex collet chuck, and the cuts were surprisingly easy. 

Like Bogs I had written down a list of X-Y coords for each cut, and it took only about an hour or so for all 5. Having a DRO on the lathe makes this a much easier proposition. Then I reversed them in the chuck to cut down the bottom spigot to length. One thing I did differently was using a 1/16" parting tool to turn down the three bottom fins; this avoided the thin wires that would result from using the thinner tool.






My list of to-do parts is getting smaller. I still need to drill the many, many holes in the heads and make the 5 pistons, and then I can think about some assembly, a base for mounting, and some sort of air manifold.


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## Penguingeoff (Oct 21, 2009)

Gday all. Just ordered the Halo plans and castings from Liney. The thread and video sold me. I am also building the PM lathe which I plan to power by the Halo on steam. I will post when I start it. Geoff. PS, I live in PENGUIN, Tasmania.


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## kvom (Oct 21, 2009)

That combination should be really interesting!

FWIW, the kit doesn't have castings, just bar stock and fasteners. I ordered just the fasteners and used my own metal.


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## kvom (Oct 21, 2009)

I had a little more shop time before leaving for the long weekend, so I "caught up" on some tapping. This model needs a lot of tapped holes. Each of the 5 cylinders and their attached parts total 20 2-56 holes.  Without the tapping stand I made a short while ago this would have been mission impossible.  ;D


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## Deanofid (Oct 22, 2009)

Man.. That's a lotta little holes to tap. I had about 10 little bittys to do today and that was enough at one time. 100 tapped holes at a whack is real dedication!

Enjoying your build.

Dean


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## Penguingeoff (Oct 23, 2009)

Now to put the cat amongst the pidgeons. Correct me if I'm wrong, but with the cam proflie being what it is, it looks to be an easy job to add another 4 cylinders and turn it into a 9. If you are making 5 cyclinders , not much extra time for another 4. Once I start will make a 5 and a 9. Geoff


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## cfellows (Oct 24, 2009)

Penguingeoff  said:
			
		

> Now to put the cat amongst the pidgeons. Correct me if I'm wrong, but with the cam proflie being what it is, it looks to be an easy job to add another 4 cylinders and turn it into a 9. If you are making 5 cyclinders , not much extra time for another 4. Once I start will make a 5 and a 9. Geoff



How about 10 cylinders...

http://www.homemodelenginemachinist.com/index.php?topic=3835.msg39257#msg39257


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## kvom (Oct 29, 2009)

After a 4-day weekend offroading the Jeep and 3 more days doing various maintenance work, I finally had an afternoon in the shop to get back to the engine.

First I finished all of the remaining drilling on the 4 headers (I will need to remake the 5th). Then I put one of them together completely along with the cylinder. Here's a looksee:







Originally I was going to leave the valve cover thicker than the plans, as I had made them from .25" thick brass plate. However, I needed to attach them with the shortest screws, so the options were to machine them thinner or cut the counterbores deeper. FWIW, I milled the counterbores with a 3/16" endmill; the plans show using a 1/8" endmill, but since the head of the screw is larger than that milling the bores is more complicated/tedious.

Some of the brass plungers were a bit too large to fit the holes, even though I measured them at .125" and the holes were reamed with a .126" reamer. Once they're machined they are a PITA to hold and polish down to size (I used a needlenose plier). So a recommended alternative would be to make the heads first and test for fit on the lathe before parting off and machining the heads.

Next step is to clean up the interiors of the cam housing and crankcase, plus part off the crankcase and make some pistons. Then it will be time for a trial assembly. I also need to start thinking of a mount design.



> Now to put the cat amongst the pidgeons. Correct me if I'm wrong, but with the cam proflie being what it is, it looks to be an easy job to add another 4 cylinders and turn it into a 9. If you are making 5 cyclinders , not much extra time for another 4. Once I start will make a 5 and a 9. Geoff



It doesn't sound that easy to me. The dimensions of the crankcase allow space for only 5, so a 9 cylinder model needs smaller cylinders or a larger crankcase. If you are good with cad/cam software then I suppose getting the correct dimensions would be doable.



> How about 10 cylinders...



If you made two 5-cylinder engines and connected them back to back with a common crankshaft then most of the dimensions would remain the same. However, I don't think that would be as attractive as the piston rods and cams would then be hidden from view. Unless the crankcases were made of lucite.  ;D


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## ariz (Oct 30, 2009)

this is a very nice piece of work kvom!

1 of 5 done! go kvom go


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## Deanofid (Oct 30, 2009)

Looks really good, Kvom. Really good. Seeing it put together as a complete assembly really shows off all your hard work, (and skills)!

Dean


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## zeeprogrammer (Oct 30, 2009)

You're such a tease kvom.
I'm liking it.


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## kvom (Oct 30, 2009)

I had another full afternoon in the shop. Today I started with the pistons. Chucking some 1/2" diameter aluminum rod, for each I turned 1/2" length down to .375 and individually fitted each to its own piston, trying to attain a rough sliding fit. Then I parted each off,

To finish a piston, I chucked it in a 5C collet block with .25" exposed, then placed the block vertically in the mill vise. I used an edge finder the first time to find the center. First operation was to mill off the nub from parting and bring to length.






Then with a 1/8" endmill (1/16" for the master piston) I cut a slot .200" deep, then widened the slot .003" on each side with two more passes.






Then it was a simple matter to chuck the collet block horizontally and spot drill/drill the cross hole for the wrist pin. Once removed from the collet and deburred, I was able to assemble the conrods to the pistons using the pins supplied by Liney. The holes are not a press fit, but I doubt that's critical. Here's a "family" portrait:






The pistons still need a bit of toothpaste lapping to slide smoothly. I didn;t cut any oil grooves but I did chamfer the tops of the pistons.

After smoothing the inside of the cam housing with Scotchbrite, I wanted to do a trial assembly of the front portion of the engine.  The first task was to machine the bearing carrier to its planned thickness of .125".  I had previously parted it off oversize and needed to removed .016" from the back. To do this I decided to use my "new" chuck with soft jaws on the lathe. I had made the jaws over a month previously, but this was the first opportunity to try it.

First, I machined a pocket .100" deep and 1.275" in diameter to match the part. This allowed me to then chuck the disc securely and take the facing cut:






Now after deburring, I laid out the components for assembly:

Cam housing, front bearing, driveshaft, rear bearing, and bearing carrier:






The rear bearing is a tight fit to the bearing carrier:






Then screw the bearing carrier to the cam housing to complete the assembly:






It's important that the bearing carrier press both bearing firmly against the driveshaft to eliminate any slack but not so that the "preload" causes binding. I need to do some tweaking here. I also noticed a few more issues to fiddle with.

1) The plunger holes are slightly too small for the supplied ball bearings to slide freely, so may need deburring or mild filing.

2) The rear cam seems a bit too far forward and may be interfering with the front plungers. I may need to add a shim.

3) The crank is not sitting perfectly straight on the end of the shaft. I suspect the counterbore bottom is not flat. In any case, the thickness of the crank or depth of the counterbore can be modified to center the conrods under the cylinders, so I will hold off until I'm ready to fit the crankcase.


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## zeeprogrammer (Oct 30, 2009)

Nice again kvom. I do enjoy the detail.


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## kvom (Oct 31, 2009)

I had a couple of hours before the Halloween visitors start arriving to tweak the cam housing issues.

I discovered upon inspection that the front cam was not seating flat against the driveshaft flange. With tight tolerances on all the parts, the clearance holes were not large enough to allow the screws to enter perfectly straight. I drilled them out with a #43 drill as opposed to the original #42, and with some careful tightening both cams set flush.

Since the camming surfaces are so close to the inner diameter of the cam housing, it's important that the shaft and cams be as perfectly centered as possible. How the bearing carrier is screwed to the housing is important, as it seems that the slightest cant in the carrier can cause the cams to rub. So tightening the screws evenly all around going in circles was necessary. I marked both the carrier and housing to ensure that any reassembly matches up the same set of holes.  When assembled, the bearing preload seems good, so I don't think any adjustment will be needed.

I cleaned up the pushrod holes, and now the supplied ball bearings and my brass pushrods fit nicely.

I also parted off the crankcase and turned the back flush, so that I can start thinking how to build a base.


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## kvom (Nov 1, 2009)

Got into the shop around noon, and decided to verify that the pushrods would correctly activate the rocker arms and valves as designed. The pushrods are just 1/16" drillrod 1.4" long, so I cut off a couple with wire cutters and filed the ends. Here's the assembly with one cylinder:






It seems to work! At least the plungers that activate the valves go up and down. It takes a fair amount of force to turn the shaft with just fingers. As Liney suggestes, I will need to attach a small chuck or the equivalent to turn it manually with all 5 cylinders mounted. I may need fewer turns on the springs as well.

Given that assembling further without something to hold the engine securely would be difficult, I spent the rest of the session making the first part of an engine mount. First, I took the piece of aluminum from which I parted the crankcase, faced it on the lathe, and then drilled and tapped 5 holes to match the rear mounting surface of the crankcase.






Next, I found a piece of aluminum plate that had a hole in a useable spot, and with the aid of a little trig and the DRO, I drilled holes to match the jig.






Then after enlarging the hole a bit on the mill, I mounted the plate on the jig...






... and milled the hole to match the innder diameter of the crankcase.






Successful test fit:






Some more milling, flycutting, on the rotab and vise yielded this:






A test fit of the crankcase and a couple of cylinders to show that there is clearance for air supply:






I won't be able to complete the mount until I get a propeller and determine the necessary height above the base, but this part will be very useful in assembling and testing.


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## Deanofid (Nov 1, 2009)

Things are looking better all the time, Kvom. I like how the crankcase, cam housing, and bearing carrier (star shaped part) came out. They look very "aero", if you get my meaning. Thanks for the progress updates. I really like the appearance of this engine, and following your work.

Keep up the good work, etc!

Dean


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## zeeprogrammer (Nov 2, 2009)

Wow kvom. It's looking good.


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## kustomkb (Nov 2, 2009)

Nice work.

I love the sound this engine makes.


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## Krown Kustoms (Nov 2, 2009)

Looks great, I love the mount.
Simple yet effective.
-B-


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## kvom (Nov 2, 2009)

Not much time to work on it today. I decided to mount all of the cylinders and see what it takes to get the pistons and conrods hooked to the crank. Mounting the pistons to the crankcase isn't so easy as the tolerances are quite close. The clearance holes for the 4 screws leave almost no wiggle room. I'd advise a future builder to go up one size (e.g., #42 instead of #43) on the holes, and also take the bottom spigot down to .495" or so. In fact, I'd probably recommend going larger on almost all of the screw clearance holes to make assembly easier.

Once I got the cylinders screwed on, I decided to just remake the crank as it will not sit straight on the end on the shaft. I got the mounting holed drilled and the counterbore done, and parted it off. Now I need to face the parted side and thread the hole for the crank pin.

The final parts fabrication will be to cut four pieces of 1/16" drill rod .150" long that pin the 4 conrods to the master rod. These are "loose" and restrained on either end by the crank and the collar of the crank pin. Getting everything together and in place might be an exercise in dexterity. I'm thinking the easiest way may be lay everything carefully on the crank pin collar and try to each the crank onto it.  I'm also not sure if the assembly of crank, conrods, and pistons can be fitted with the cylinders on the crankcase.  If so, that will be my preference.


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## kvom (Nov 4, 2009)

I tried a little assemble of the conrods yesterday, and found that there are a few problems to overcome.

First, I had neglected to round over the ends that attach to the master rod, since these aren't visible when the engine is assembled. However, unless I do so, then the corners will hit the crank pin. So I will need to file all 4 ends to clear the crank pin.

The second issue is that the assembled rods and crank pin cover the mounting hole for the crank, meaning the crank needs to be attached to the crankshaft before attaching the pin and rods. So I will need to attach the front of the engine to the crankcase with the crank attached, or else attach the crank to the crankshaft+bearing carrier and then try to fit it all together.

The second problem is the tiny pins that connect the conrod to the master rod. I had no luck trying to get one together using some needlenose pliers, so I will need to try again using some tweezers.


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## kvom (Nov 8, 2009)

Since I blew a start cap on the RPC this week, the lathe was out of operation until this weekend. Once I got things back together, I finished remaking the crank, and it now sits square on the shaft. I also managed to file the ends of the conrods so that they will assemble with the master rod and the crank pin.

So now comes the problem of assembly. I discovered that there is no way to insert the assembled conrods/pistons with the cylinders attached. So my plan is to insert the pistons into the clyinders with the conrods attached, and try to assemble the rods inside the crankcase. If that proves too hard I can try it without the cylinders and and/or pistons, and then install the cylinders over the pistons.


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## Bill Mc (Nov 9, 2009)

Hi KVOM - I know this is a little off subject but I think I also have a defective start capacitor on my Chinese lathe (Busy Bee Craftex CT039). I have to give the chuck a spin when I turn the lathe on to get it rolling. Could you give me a heads up on diagnosing and correction of this problem? Is it hard to fix? Thank you - Billmc


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## kvom (Nov 9, 2009)

In my case the capacitor blew its top, so it was quite easy to locate and replace. No help on the lathe I'm afraid, although if it's a 1-phase motor you can usually remove/replace the cap.


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## kvom (Nov 9, 2009)

After a lot of unsuccesful fumbling, I finally figured I would never get the conrods attached while they were in the crankcase. So I disassembled everything, and was successful in pinning the rods together.






The pins themselves were a bit of a struggle: 1/16" drillrod .150" long. In order to get them cut to length I made a "jig" by milling a small piece of aluminum .15" thick and drilling a 1/16" through hole. I inserted some drill rod, cut it off close with a wire cutter, and then filed it flat to the jig. Still, these are the smallest "parts" I've ever had to deal with.

With the rods assembled, they can be inserted into the crankcase via one of the cylinder holes:






Then I attached the front section to the crankcase and screwed the crank pin to the crank.






I discovered that I needed to file the profile of the master rod so that the screw attaching the crank to the crankshaft is accessible with the rods attached. This is because the timing is adjusted by rotating the rods relative to the cams.

Next session I'll attach the pistons to the rods and then the cylinders to see what kind of friction there is in the works.


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## zeeprogrammer (Nov 9, 2009)

This is great kvom. Looking forward to seeing the pistons and cylinders assembled.


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## Brian Rupnow (Nov 9, 2009)

By now you can understand the true meaning of "picking fly$hit out of pepper"!!!


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## Deanofid (Nov 9, 2009)

Good work, Kvom. I enjoy your assembly fit-ups almost as much as your construction. 

Dean


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## ariz (Nov 10, 2009)

it's going to be very interesting now   

you're doing a great work kvom, I'm curious to see the next step, pistons & cylinders  :


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## kvom (Nov 11, 2009)

This afternoon I took a short time to attach the pistons to the conrods, and then slide the cylinders over the pistons to attach them to the crankcase:












After a bit of twiddling the engine turns very smoothly with finger pressure, *except* if the screw for the crank pin is turned down tight, binding the conrods.

I'm pretty sure I know the reason for this. When I milled the crankcase I left the front edge an extra .01" or so from the center line, intending to have room for adjustment later. Well, the time for adjustment has arrived. There are several options for aligning the conrods:

1) Mill a bit off the front of the crankcase
2) Make the crank disk thicker
3) Make the crank pin longer

I think the one I'll choose eventually is none-of-the-above. The next time I disassemble the engine I will make an insert a thin brass washer between the crank pin and the disk.

I don't think leaving the crank pin screw slightly loose is a good option, as the rotation of the engine will tend to cause the screw to tighten.

I received a package from Enco today with a supple of 1/4" hose barbs, so I will think about making a manifold to supply air to all 5 cylinders.

I noticed when turning the crank that the pistons expose most of the wrist pins when at their lowest point. It might be a good idea for future builds to make the cylinder spigot slightly longer. That said, the chance of a pin working loose is pretty remote.


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## Brian Rupnow (Nov 11, 2009)

Kvom--I had to do the same on the radial I built. I used a 0.25" long shoulder bolt as the crank pin, and the hub was 0.25" thick. I didn't want to disassemble everything, so I made a very, very, very thin washer out of brass and put it under the end of the shoulder bolt to free up the hub.---Brian


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## zeeprogrammer (Nov 11, 2009)

That's looking very fine kvom. Nice.


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## ariz (Nov 12, 2009)

:bow: :bow: :bow:

now it looks like a radial engine! wow, all those parts together in synchronicity


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## Maryak (Nov 12, 2009)

kvom,

Catching up with things since my moving experience.

I LIKE IT. :bow: :bow:

Best Regards
Bob


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## kvom (Dec 3, 2009)

I have been spending shop time working on the Jeep, but decided to finish a small step on the Halo.

In order to provide a grip to set the timing as well as provide some flywheel effect during tuning, Liney recommends attaching a small weight to the propeller shaft. I had recently gotten a broken driveshaft from an offroad buddy, and decided to use the splined end to make this. I mounted the shaft in the lathe and faced the end, drilled a 1/4" hole, and then sliced off a 1" piece on the bandsaw. I then used the mill to remove the saw marks.

The next step is to provide a means of securing the weight to the shaft. Based on an earlier suggestion, I obtained some #4 lead shot from a shotgun shell. These will be used to press against the shaft. Since the shot measure 1/8" in diameter, I drilled a 1/8" hole through to the center. Given the splines on the sides, the hole was made with a 1/4" endmill to create a flat spot followed by a 1/8" endmill to mill the hole.






I need a set screw to hold the shot in place, and a 8-32 is the next size up where the tap drill is > 1/8". The particular steel was quite hard to tap, as it feels "sticky". Fearing breaking off my tap, I managed to make only about 4 threads, so I hope these are enough. Here's a shot of the weight mounted on the engine shaft:






The brass rod was there to tamp down the lead shot into the hold. In didn't have a 8-32 setscrem on hand, so that is another item on the shopping list.


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## kvom (Dec 4, 2009)

To get a runner, I will need to supply air to all 5 cylinders individually. So I made this simple manifold for a small piece of aluminum bar.






Drilled 3 through holes and threaded the 6 openings 1/4-27 NPT. Then 5 hose barbs for 1/4" plastic tube and ther 6th hole for the regulator line.

The "tuning" instructions are to do each cylinder individually, where you are primarily setting the length of the pushrods so that the input and output valves open and close properly. I realized that I could do this with the tubing attached to all of the cylinders by having only the cylinder being tested have pushrods installed. On a cylinder without pushrods the input valve will be held closed by the air pressure.

This manifold is a temporary fixture; I hope to incorporate a better design into the final design of a stand and base.

We are going offroading tomorrow (snow possible ), so if I don't break anything on the Jeep I might be able to make some more progress on the engine next week.


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## cobra428 (Dec 4, 2009)

Kvom,
Looking good man. That gets heads and valves?? Oh, I picked up an electronic non wiggler. Man that thing is awesome :bow:M y thank you for turning me on to that. I was going to get one a while ago and I said ahhhhh, it's the same. As I'm sure you know, wow this it is dam accurate tool.

Thanks Again

Tony


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## kvom (Dec 8, 2009)

Despite a list of things I "should" be doing, I spent most of the afternoon doing some fit and assembly of the heads to the cylinders. For any interested onlookers, here's the procedure (just repeat 5 times).

First, place the valve balls into the input (left) and output valve bores.






I found it tricky to get the depth correct, so before further assembly I tested each visually by pushing the plunger while looking to see that the ball moves upward. If not, the bore is not deep enough. Using a depth mic, I determined how much more was needed to reach the indicated .185". Then I chucked the head in the vise and used a #8 reamer in the mill to deepen it. Mostly I needed around .005" or so.

Next, fasten the valve cover to the head, making sure that the inlet hole is on the left.






Next the head must be attached to the cylinder. Note that one hole is counterbored do allow the rocker bracket to sit flat. For this reason the bracket is attached after the head.

The plungers are now inserted along with their springs. I cut down the springs to 3 turns to reduce the force on the cams. We'll see if it need more or less when we try to get it to run.






Finally the rocker bracket and arms are attached.






With all 5 heads assembled, we have this front view:






And from the rear:






I need to get some more plastic tubing to attach my little manifold, and then cut the pushrods to length before the first trial with air.


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## Deanofid (Dec 8, 2009)

Really looking good, Kvom. Quite a bit to putting it together, it seems. 
Pretty exciting, getting so close to air time!

Dean


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## zeeprogrammer (Dec 8, 2009)

Like Dean said...exciting. It looks great.


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## kvom (Dec 9, 2009)

This afternoon I hooked the manifold to the engine and applied 5 PSI air. As I feared, there is significant leakage around the input valve seats. Of 5 heads, only one seals completely. Three others have smaller leaks (e.g., when I push in the plunger the airflow increases significantly). The last head seems not to seal whatever. 

What I should have done, prior to assembly, is test each head's valves. If I insert the balls and apply air, then no air should escape. Similarly, I can turn the valve cover around so that the input barb is over the output valve and test it in the same way. In testing the output, air will still flow out the bottom, but not from the side exhaust hole. Blocking the bottom hole should result in no air flow at all.

So I have made a simple manifold with just one output barb that should make this testing easier. However, when I discover which valves are defective, I'm not too sure I'll be able to fix them.

For other builders, this testing might be appropriate while partially machining the heads. If you drill/ream the plunger holes, drill the valve holes, and drill/tap the valve cover holes, the valves can be tested before doing the rest of the machining of the heads. Just an idea. If I have to remake the heads I will likely test them this way.


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## kvom (Dec 10, 2009)

Thanks to a suggestion to seat the balls in the valve bores (from Cedge and Chuck Foster) by tapping them in with a drift and a hammer, I think I can get the valves to work. I did the first 4 before it was time for dinner and a rest. The seating isn't absolutely perfect in all of them, but hopefully good enough. 

I did find a few things for other builders to watch out for. First, the hole for the inlet barb isn't completely over the inlet valve bore, and the threaded portion of the barb is thicker than the valve cover. So when I tightened the barb I got leaks between the cover and the head. So when seating the balls I also gave the inside surfaces a rub with 360 sandpaper and Scotchbrite. 

I was also finding a fair amount of small swarf, including some round "wires" that seem to result from the drilling/reaming process. I made sure to pick these out with tweezers and also to blow air through all the passages. I think the wires are burrs created when drilling/reaming the holes for the plungers. I drilled these holes first and the valve bores last, but perhaps the order should be reversed.


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## zeeprogrammer (Dec 10, 2009)

No one doubts you can fix it. Just a matter of time.

Here's hoping it's very little time.


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## dreeves (Dec 10, 2009)

In Looking over the prints for the engine I did not find any reference to the ball. I understand how it will work but one question. Is there springs to push pressure on the ball to seat them?


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## kvom (Dec 11, 2009)

dreeves  said:
			
		

> In Looking over the prints for the engine I did not find any reference to the ball. I understand how it will work but one question. Is there springs to push pressure on the ball to seat them?



Seating is provided by air pressure on both valves. For the input valve the pressure is "direct". When the input valve is open air enters the cylinder and also flows, via the exhaust route, to the output valve, which will be closed.


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## dreeves (Dec 12, 2009)

What Dia. Balls are used?


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## kvom (Dec 12, 2009)

Per the plans, the ball needs to fit inside the .200" bore and seat on the .156" bore. I didn't measure but I think they are 3/16".


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## dreeves (Dec 12, 2009)

Thanks, My plans do not even mention balls are used. I have redrawn the engine in autocad


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## kvom (Dec 12, 2009)

There are two sizes of balls used. The 3/16" for the valves, and 1/8" balls for the rod lifters. These small balls ride on the cam surfaces; the rod plungers sit on top of these; the pushrods connect the plungers to the rocker arms. 

Rather than any assembly drawings, Liney provides a set of transparent sheets with various assemblies drawn to scale. By putting these on top of each other you get an idea of how the parts interact.

Today I spent a couple of hours in the shop. The first order of business was to make a new "flywheel", as the one I made from the end of an axle shaft was too hard to tap for a set screw. I made the one in the photo from a scrap piece of hex 12L14 steel. I drilled the cross hole 1/8", then counterbored with a #7 drill and tapped for the 1/4-20 screw. There are 3 #4 lead shot between the engine shaft and the set screw.







After finishing seating the valves in the last head, I worked a bit on the pushrods. These are simply 1.4" lengths of 1/16" drill rod. I cut them a bit long with a wire cutter, then filed both ends flat and to length. However, my first fitting showed them to be a bit short. So now it seems that either I need to have longer rods, or else the valve plungers need to extend higher from the heads. The latter means that the springs may need to be longer.

From the plans, the cams have a radius difference of only .05" between the open and closed valve positions. This means that the plungers will only move .05" to open the valves. Somy next shop session goal will be to determine where then plungers need to be in the closed position, and adjust to suit.


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## kvom (Dec 14, 2009)

Did a couple of small tasks on the engine:

First I remade the crank pin a bit longer so that I could tighten the screw without binding the piston rods. There is really no reason that it can't be longer than the plan's dimension.

I "discovered" that I had failed to machine the pocket in the head that I was test fitting the pushrods on. That meant that the rocker and its arms were .05" too high. Hopefully the next time I put it together things will fit better.

As far as I can tell, I have everything set to try a test run the next time I get into the shop.


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## ariz (Dec 14, 2009)

wow, can't wait to see the results......


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## zeeprogrammer (Dec 14, 2009)

kvom  said:
			
		

> As far as I can tell, I have everything set to try a test run the next time I get into the shop.



Pic! Pic! This will be great!


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## Cedge (Dec 14, 2009)

Zee, Kvom....
We've all been cheering both of you on and watching all your hard work as it has come together. With both of your engines nearing completion, you two are just about to create the perfect storm for the POM voters....LOL 

Steve 

Steve


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## Deanofid (Dec 15, 2009)

Cedge  said:
			
		

> Zee, Kvom....
> We've all been cheering both of you on and watching all your hard work as it has come together. With both of your engines nearing completion, you two are just about to create the perfect storm for the POM voters....LOL
> Steve



No kidding!!

Dean


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## zeeprogrammer (Dec 15, 2009)

Now stop that! I'm hardly in kvom's league.
But I'll be happy to be a nominee and make his win easier. ;D
Please return to the original broadcast. ;D

Much appreciated.


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## kvom (Dec 15, 2009)

Thanks for everyone's support. But to be realistic, even if it turns over on the "test stand" I will still need to make a suitable base plus a manifold to replace the 5-armed monstrosity I cobbled together. I have some ideas on this, but nothing solid yet.


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## kvom (Dec 17, 2009)

I did the recommended tuning and adjustments as recommended by Liney for the first cylinder, and after some fiddling got a runner. Here's the evidence:

[ame]http://www.youtube.com/watch?v=IvhgMdTBUYM[/ame]​
To get enough flywheel weight I clamped my tapping station chuck onto the shaft. On the video, I started it at 40 PSI and gradually reduced the pressure to 20 PSI at which point it stops. With more cylinders and some run-in I expect it will run at a fairly low pressure. For other builders I will reiterate the setup process and some issues I encountered.

My first "concern" was realizing that the pushrod holes in the cam housing are not centered on the cylinder. It seems that my setup on the rotab was a bit off. While the drawings from Liney show the pushrod for the inlet valve connected to the rear hole, I decided to reverse this to make the rods more upright. Since the cams are symmetric, this isn't a problem as long as all cylinders are set the same.

The first adjustment is to set the crank pin/conrods relative to the cams. This is the sole timing adjustment and is needed only for the first cylinder. I slightly loosened the screw that holds the crank to the shaft and then turned the shaft until I felt the inlet cam contact the ball bearing that pushes the inlet rod. Holding the shaft steady, I pushed on the crankpin so that the piston was at TDC (i.e., you want the inlet valve to start to open at TDC). Now it's time to tighten the crank to the shaft; however, the conrod blocks access to the screw head, so I needed to slowly rotate the shaft and crankpin together until I could get to the screw with a small screwdriver. It's for this reason that you need some friction with the screw initially: loose enough to be able to adjust the crank pin but tight enough so that the pin turns with the shaft. Note that I set it up so that the engine turns CCW as seen from the front; to reverse this direction turn the crank pin 180 degrees relative to the cam.

Next, the travel of the rocker arms needs to be adjusted. Connect air at low pressure and turn the shaft until the inlet valve is open. Then adjust the outlet rocker via the SHCS until air is coming out of the exhaust. Next back it off until no air is exhausting. The exhaust pushrod length is now set. Now you can lock the adjustment screw with a 2-56 jam nut. The small issue I had with this is that the screws supplied may not be long enough to protrude out the top of the rocker. For this reason, I plan to use longer screws on the other cylinders and cut off any excess once the jam nuts are in place. A 3/16" nut driver is an excellent tool for tightening these small nuts.

The same procedure is followed for the other pushrod. Turn the crank so that the exhaust is open and adjust the inlet pushrod until air enters the inlet valve; then back off and lock the jam nut.


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## shred (Dec 17, 2009)

Sweet, it runs.. only 4 more cylinders to go, right?


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## zeeprogrammer (Dec 17, 2009)

Fantastic! I bet that felt superb!
When you got it going an 'oh!' popped out of me.
Congratulations.


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## Deanofid (Dec 17, 2009)

That one cylinder has a lot of work to do all by its lonesome. Once you get its pals bolted up, I'll bet it runs down nice and slow, and on a lot less pressure.

Good going, Kvom.  Will be great to see it all up and swinging a prop!

Dean


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## kvom (Dec 18, 2009)

Last night I started to assemble the other cylinders. With two installed the engine wouldn't run, although each would kick the piston. I suspect that the additional resistance of the springs plus the cams against the followers stalls it out.

So I just added each cylinders, adjusting the valves as described above. When I got to the last one I discovered that one of the rocker arms was sitting cockeyed; looks like it wasn't chucked properly when drilling the cross hole. Luckily I had made one extra arm, which needs only to be drilled & tapped. So once I can do that I can try a 5-cylinder run.


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## kvom (Dec 19, 2009)

My first 5-cylinder trial was not a success.  ???

First I had to remake the skewed rocker arm, and the blank I had left over from the first batch was too thin. So I spent probably an hour making one from a bit of 1/4" thick aluminum. Note to self: finally buy a set of thin parallels.

Once assembled, the last head seemed pretty leaky on the output valve, but I decided to hook it up anyway. Applied air up to 60 PSI without a runner. Then I noticed that the crank had become loosened from the shaft so that it wasn't turning. By then it was to late to pursue a readjustment.

With all cylinders attached, there is a fair amount of force needed to turn the shaft by hand. Lifting the pushrod to open a valve has a hole train of friction and resistance to overcome, and since there is only one piston delivering a power stroke at the point of contact it needs to have enough power to overcome the resistance. A heavier flywheel would help as well.


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## zeeprogrammer (Dec 19, 2009)

First trial was a success.

A trial is unsuccessful when nothing is learned.

We all know you'll get there.


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## vlmarshall (Dec 19, 2009)

zeeprogrammer  said:
			
		

> First trial was a success.
> A trial is unsuccessful when nothing is learned.


Now, THERE'S a cool quote. ;D

Keep at it, man, and keep us updated. You'll get it, and I wanna see it.


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## ksouers (Dec 19, 2009)

zee, I like that! Mind if I steal it?

kvom, I know you'll get it figured out. It's always the basics, one step at a time.


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## rleete (Dec 19, 2009)

Wow, that sounds great, even with only one cylinder. Can't wait to hear the finished engine.


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## kvom (Dec 27, 2009)

Rather than work on getting the engine to run, I decided to start building the manifold, which will be a lot more practical than the temporary "octopus" I cobbled together. So getting back into the shop after a few days away visiting relatives, I fabricated the two pieces shown to the right of the engine mount I made earlier:






The center part has the circular air canal, and the brass part on the right is the cover. All three pieces bolt together and attach to the crankcase as shown here:






To make it operational, I need to make/find 5 small hose barbs that will attach to new holes in the brass cover, as well air inlet barb.

FWIW, the aluminum part is .5" thick, and the brass cover is .2" thick. The air channel is 3/16" wide and .35" deep.


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## kvom (Dec 30, 2009)

I decided to make the hose barbs myself using some .25" brass round. Nothing too complicated other than some tedious tool changes on the lathe. Outer barb diameter is 3/16", with the inner diameter 1/8" and the air passage 1/16". I then drilled the mounting holes in the manifold cover, reamed oversize, and fixed the barbs with red loctite. The inlet barb I just cut from a store-bought connector and loctited to the body of the manifold.







With the loctite cured overnight, I assembled to the mount and crankcase.






Then it was time to connect some platic tubing.






I gave the moving parts a dose of oil and hooked up the air. Unfortunately things went less well from there. It turns out that the inside seal between the manifold cover and body isn't airtight, and all the air is exiting there rather than going to the cylinders. So my plan is to make a gasket from oiled kraft paper, as shown on a recent thread.

As I was disassembling the manifold from the engine, I noticed that it wasn't screwed tight. So now it seems that the mounting screws are several threads too long, meaning that the cover was not cinched down tightly to the body. Rather than cut the screws down, I'm still going to make the gasket first. 

While everything was assembled, I did a few minutes run-in with the electric drill, and the mechanism doses seem to be turning with less force. I may attach it to the mill spindle and let it turn at low speed for a longer period while the gasket making gets underway.


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## kvom (Dec 30, 2009)

We have a runner. ;D That is all.

















































Film at 11 (or when my daughter tells me where she hid the camera)  :big:


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## Deanofid (Dec 30, 2009)

That's a dirty trick, Kvom! I scrolled down, then a little more, then all the way. No movin' picture!

I'm glad you got it going, and I'm staying up 'til 11 waiting to see.
It's quite a build. Heck, each jug and head is a build on it's own!

Tapping my foot.

Dean


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## kvom (Dec 30, 2009)

[ame]http://www.youtube.com/watch?v=0ia59lEwFEQ[/ame]​

After the early afternoon trial, I made a paper gasket and oiled it to try to seal the manifold. I still needed to shorten the screws to get everything tight.  I also hooked the shaft to the mill and ran it for about 30 minutes at ~300 rpm. At the end, the mechanism was slightly less tight.

I then needed to readjust the timing. The connection of the crank to the shaft is by a single flat-head screw. If the engine is turned the wrong way, the screw will loosen and the crank will not be turning. *So it is important that the engine only turn clockwise as viewed from the front*.

I also adjusted the timing so that the piston is slightly past TDC when the inlet valve opens.

Once all this was done I reattached the air and started to turn the engine by hand via the attached chuck. I started to feel a bit of a kick, and then it sprang to life. The manifold is still leaky, but not as badly as before so that the cylinders are getting air. I imagine that with a better sealed air supply it should run at lower supply pressure.


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## Deanofid (Dec 30, 2009)

Great!! And I didn't even have to stay up late to see it. Thanks for the vid, and congratulations!

I know you'll get it smoothed out. You've got the hard part knocked.

Dean


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## zeeprogrammer (Dec 30, 2009)

Congratulations kvom.
Thanks for the vid.
It's wonderful.

Yeah when I saw the other post I was thinking, 'dirty rotten scoundrel tricky thing to do' ;D but I kept checking in...glad I did!


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## rake60 (Dec 30, 2009)

Runs pretty damn good for having, "a little friction in the system".

Congratulations kvom on a magnificently documented build! :bow: :bow: :bow: 

Rick


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## Maryak (Dec 31, 2009)

kvom,

Great stuff. Your persistence has sure paid dividends. :bow:

Congratulations for a fine engine. :bow:

Best Regards
Bob


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## ariz (Dec 31, 2009)

congrats kvom, great running engine, great looking one too, and a very well documented build :bow: :bow: :bow:

you may be very proud of it! 5 cylinders (so 5 pistons, 10 valves, etc.), lot of work and everything that must run in synchronism... well done :bow:


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## ozzie46 (Dec 31, 2009)

Congrats. Nice runner. Persistence pays huge dividends. I never had any doubts. :

 Ron


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## Brian Rupnow (Dec 31, 2009)

Kvom---Its been a great thread, and you've done a magnificent job. congratulations!!!!--Brian


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## kvom (Dec 31, 2009)

Thanks to everyone for following along. Credit is due to John "Bogstandard" for first pointing me towards this engine and also for demonstrating how to cut very thin fins in the cylinders.

I still need to make a suitable base as well as fix up the manifold. I'm thinking I may try some RTV in place of the gasket. Or I may try a different design.

Then I'll need to study up on polishing and bling, as this and my previous builds all need some.

For anyone considering this build, I can recommend it as a "step up" for those like myself who have done a couple of builds. My thoughts are:

1) The tolerances are not particularly tight, except in a couple of places.

2) I was initially intimidated by the use of 2-56 screws for all the fasteners, but in reality they pose no problems whatsover. I didn't break any drills (50 and 43 for the holes) nor a tap. Use of a tapping stand or equivalent is a definite requirement. Since I have a DRO on my mill, lining up the clearance holes to the tapped holes was straightforward. That said, there is no reason that the clearance holes couldn't be drilled somewhat larger to make fitting easier.

3) A rotary table is a requirement for this build, and was the major tooling expense I had. I made soft jaws for the rotab chuck, and these made precise positioning on the rotab much easier and faster.

4) Other tools I bought to make the build easer were a set of O/U reamers and the 2-56 HSS taps. Buying the fasterners and bearings from Liney along with the plans was also a good idea, as there were 5 different lengths of screws, the two bearings, hose barbs, wrist pins, and all the little balls. While everything could be sourced elsewhere, having everything delivered in one package was very convenient. I did buy a box of 2-56 x 1" SHCS as extras.

5) Materials are pretty flexible. While I used brass for the cylinders for looks it's not really a necessity. Aluminum can be substituted for brass in the cylinders and heads. In any case, I bought the brass rod needed for the cylinders on eBay for less than $15, of which I used only about a quarter.

6) While I used a CNC lathe to make the cam housing, it wasn't necessary to do so. Turning the rounded profile on the nose was easy with CNC, but could also be done manually with a bit more effort. The actual shape of the nose profile isn't critical in any case.

7) To cut the very thin fins on the cylinders I needed a surface grinder to make the grooving tool. The fins are of course decorative and a normal cutoff tool could be used for wider fins (or no fins at all).

And finally, it should be possible to make this engine with fewer cylinders given suitable modifications to some measurements.


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## vlmarshall (Dec 31, 2009)

Congrats! I really like the way these things sound. :bow:


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## GailInNM (Dec 31, 2009)

Congratulations on a very nice build. Thanks for the journey.
Gail in NM


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## joe d (Dec 31, 2009)

Kvom

Congrats and thanks from me too! I've enjoyed following along.

Joe


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## shred (Dec 31, 2009)

Sweet! Thanks for the notes and observations as well. It can be tough to look at a finished model like that and know if it's within your capabilities.


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## cfellows (Dec 31, 2009)

Nice job, KVOM. Gotta build me a radial one of these days.


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## hobby (Dec 31, 2009)

Very nice job on getting your engine running.

Excellent craftsmanship.


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## kvom (Jan 1, 2010)

I spent the afternoon rethinking and then remaking the manifold. Here's the result:






The body, made of 12L14 steel is actually two pieces. The first piece I turned as a disk 2.000" in diameter, .5" thick, and bored out to 1.250". I then used a grooving/cutoff tool to turn a groove into the outside .25" wide and .35" deep to provide the air channel. The second piece I turned 2.25" in diameter and bored .199. I then pressed piece one into the bore of piece two. Then it was off to the rotab to drill the mounting holes and holes for the air barbs.

I mounted it to the engine, and while it's not 100% airtight at the pressed seam, it's a lot better then before.

Unfortunately, the engine then decided not to cooperate by running at any pressure. Seems the crank screw had loosened up again. Arghh!

So next shop session I'll adjust the timing again and tighten the screw. I also want to check all the valve again as I didn't seem to feel proper airflow from every exhaust port.


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## dreeves (Jan 2, 2010)

Ref to the leak. Can you soft solder if at the seam?


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## kvom (Jan 2, 2010)

I am not very sure where the leaks are. The next time I disassemble the mount I plan to submerge it in WD40 and blow air in. It may not be significant. I can feel air inside the crankcase, but that can also be escaping around the pistons.


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## kvom (Jan 2, 2010)

I spent a while in the shop this afternoon getting a start on the base.







One lesson learned was that when cutting a deep slot with a small endmill, clearing the swarf as it cuts is a good idea. Cost me a 3/16" carbide endmill to learn this.


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## jack.39 (Jan 2, 2010)

A most commendable build! To say the maker is formidably competent would not do him enough justice!

So much more involved, intricate, and inspiring a project that it makes my steam locomotive look like the relic it is.

Somewhere, when I was a kid, my Dad having taken me to some sort of open house or show, an old 2-seater airplane was on display, having a big, radial engine, finned cylinders sticking out all over. My Dad, Tool & Die Maker he was, always marvelled at works of mechanical construction, and he explained to me that all those the pistons within the cylinders each had a connecting rod which somehow had to connect to a crankshaft. It troubled him no end to not know exactly how that was accomplished. I will never forget that conversation, or the fact that, years later, after he had died, my mind resurrected the scene from that show while I was looking at a picture in some book showing how a "master crankpin" was made to attach those rods...........

Thanks for listening to my story! jack


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## Krown Kustoms (Jan 2, 2010)

Great build KVOM, I learned alot.
-B-


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## gbritnell (Jan 2, 2010)

Very nice work Kvom. This certainly isn't an easy build by any means. I'm sure you'll get all the bugs out.
gbritnell


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## kvom (Jan 2, 2010)

I've had a lot of fun making this.

As far as my being "formidably competent", that's hardly true. I know Jack is being both polite towards me and extremely modest in comparing it to his loco. I'm still a newbie at this, and while the little engine looks complex it's actually pretty simple in concept. I did learn some new techniques in the build, which was one of my goals in starting it. 

There is no way I could build an engine of any sort at this stage without plans to go by. So the people I really admire on this site are those that conceive their own models and then execute them. People like George, Jack, Cedge, tel, Maryak, Gail, and many more are the real inspirations for me to try to improve.


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## kvom (Jan 4, 2010)

Sunday I took the engine "mostly" apart for some tweaking.

First job was to test the manifold for leaks. I submerged it in wd40 and applied air while blocking the barb outlets with my fingers. I got leakage from the back seam and also around the barb holes. However, In think neither of these may be a big problem. I could use a silicone sealant on the back as that surface presses to the mount and hence is not visible.

Next, I filed the leading edge of the cams where they start to lift, giving a more gradual approach. The plans call for a .125 radius, but I just eyeballed it.  With the cam housing reattached to the crankshaft I did about 15 minutes of run-in powered by the mill at 800-1000 rpm. Afterwards the shaft and cams spin quite freely under finger pressure.

Next, I tested each head's input valve individually. Four were airtight, but the 5th was not. On disassembly I found a couple of tiny pieces of swarf in the valve bore that were keeping the ball from sealing. After cleanout with brake cleaner and air, I reseated the ball and retested until I got a clean seal. This valve may have been one reason I needed such high pressure on the first test run, as the cylinder would have been pressurized full time. I noticed that there is some air leakage between the head and the valve covers, but I don't believe this will be significant.

This morning my objective was to run the engine on each cylinder solo. I did so on the first two before stopping for lunch. The first one ran on 40 psi, certainly an improvement, but the second ran on 25!

One discovery I made inadvertantly is that interchanging the pushrod positions changes the direction of rotation. Seems logical when you thuink about it, but was a surprise when I did the first run of the morning when I switched them unintentionally.


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## Maryak (Jan 5, 2010)

kvom,

Thanks for the kind words. I have yet to tackle a multi cylinder model engine and a boiler so I don't think I am quite in the same class as the others you mentioned but it sure gave me warm fuzzies. :bow: :bow:

Now all I have to do is keep clear of the "Fluffy Bunnies," especially if they are overshadowed by a pink terry towelling dressing gown. : 

tel can explain, (I hope). ???

Best Regards
Bob


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## kvom (Jan 6, 2010)

I put it all back together and applied air.  Ran a few pounds lighter (i.e., 70 PSI) but came to a halt when the crank pin came loose.  

Another reason not to run it CCW.

So it needs another partial disassembly, retuning, etc. I think I am going to put this off until I can get a polishing setup established so that I can bling it at the same time. Meanwhile I need to put the finishing touches on the paddleducks engine.

And the shop was such a mess I spent the rest of the afternoon cleaning up (and still not done).


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## ariz (Jan 6, 2010)

I understand you kvom, when an engine (or two) are about to be finished, usually the shop is such a mess that one day isn't enough to clean it...

the liney halo however is a wonderful engine and everything is worth to build it
how are going the POM votes? I voted for you, hope you catch the victory :-*


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## vlmarshall (Jan 6, 2010)

That engine really has the look of an internal-combustion radial. :bow: I can't wait to see it finished and polished.


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## dreeves (Jun 2, 2011)

KVOM,

I would like to know if your Halo is running any better since you last posted the video. I just started making chips on this engine.

Dave


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## kvom (Jun 2, 2011)

Like all my other engines (except the flame eater), the Halo is sitting in pieces in a drawer waiting for me to "bling" it and build a better manifold.   I also would want to remake the master rod, and probably then remake the heads from brass rather than aluminum. Still, it was fun to make.


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## dreeves (Jun 2, 2011)

I plan to use brass for the heads as well. Thanks for the response

Dave


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## JaguarB (Jun 5, 2011)

To stop the crank turning on the crank shaft I set mime up then using a dremmel by hand drilled and fitted a 1/16 pin as like a key / key way this is captured by the end plate / washer

yours Paul 

see

http://www.boscott.co.uk/youtube.html


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## lazylathe (Jun 5, 2011)

Great build kvom!!! ;D

Can't wait to see it all blingefied!!!!

Andrew


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