Liney RV-1 - A New Double Wide

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Sshire

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Liney RV-1 - A New Double Wide

Part 1

“The way to succeed is to double your error rate.”
Thomas J. Watson
Chairman and CEO of IBM


I had the plans for the RV-1 on the bench for a few months while I was working on the boiler. I was following Bill Lindsey’s build and didn’t realize, until he finished it, that it was smaller than I had imagined. So, all dimensions times two seemed doable.

I printed a second set of the drawings and, with a calculator to check my math, wrote the new 2X dimensions on the plans.
I went through the brass and aluminum stores and ordered what I didn’t have.
Most pieces laid out on the bench all ready for their weight reduction.



The base plate, a .375 6061 piece, becoming square.



The 2” face mill gives a beautiful surface.



Even with the DRO, I feel better marking out the piece. That way, I have a better chance of catching a screwup before it happens.



After finding the 0,0 corner and zeroing out the DRO, I plunged an end mill and began making the cutout for the flywheel. I changed to a smaller diameter end mill for the corners and finishing pass.



With the flywheel opening cut and mounting holes drilled, it was good to see that each hole was perfectly positioned on the scribe lines.



I like to mill a bevel on plates. Cutting the edge against the fixed vise jaw makes everything work nicely with the bevels all around matching at the corners. Cut, turn 90 degrees, cut, turn, etc.



First part done. Of course, more sanding and polishing will come later.



The flywheel bearing “towers” are next. I had seen these acetal bearings with stainless steel balls and though that this might be a good engine for a tryout. They are described as “no lube” if run under 2500 rpm. Maybe.


The primary problem is that they are wider than the .5” x .5” brass square. Even though there appears to be plenty of room for a wider piece, I had another idea. And I’m not in love with straight square pieces.


That looks like it might fit.



A bit of drilling and boring got me just under what I need. The engineering data for the acetal bearings gives from 0 to -.003” interference. The bearing O.D. is .625.





I’m going to line bore the last 1 or 2 thou when the blocks are mounted on the baseplate. For now, the bearing almost presses in.



Good enough for now so I parted off two pieces.



I wasn’t overly concerned with the internal finish as that will go away when they are bored to size.



For the bottom of the bearing tower, I rounded off the corners of the .5” square bar.



The two pieces are roughly to length. The action then moves to the mill to make both the same length and to mill a recess for the round bearing shells.



Ready for their debut on the soldering stage.



That’s today’s output. More tomorrow. Don’t change that channel.
 
Ought to be a real nice engine. Might have to work your compressor some to keep it running! Or are you running it on steam... :)

Chuck
 
Hey, Chuck
After I spent a month building the damn boiler (twice), it's running on steam
 
Liney RV-1 - A New Double Wide

Part 2


After silver soldering the bearing towers, I cut a piece of 2”x2” brass to rough size and then off to the mill to square it. This will be the valve block.



Switching rods in the depth mike to a 1” to 2”, I milled the block until it was close enough to a 2” cube.





Now a 1” diameter through hole for the rotary valve (tomorrow’s part du jour). Center was located and spot drilled.



Then a series of drills starting with about .25” and getting up to my largest, a .75 Silver and Deming.





I took the .75” hole out to 1” with the boring head. I really need a thicker shank boring bar that is long enough. This was the only bar I had that would go 2” deep. While the knee power feed moved up slowly, I kept fiddling with the VFD speed dial to keep the chatter to a “less than butt clenching” level.
Surprisingly, the bore had a good finish. I’m thinking that indexable boring bars might be a good idea.



The block is attached to the baseplate with 4 screws. The drawings show them as 2-56. At this scale, 5-40 look about right. Drilled and tapped.



After discussions here and with Doug at Liney, I did go with a 2x diameter hole for the intake and exhaust. Both the exhaust at the top and the intake in the back, have counterbores for the exhaust stack and intake piping. . Since I’m in the process of standardizing everything to ¼-40, thats what I drilled and tapped.





With the drilling and tapping complete, the last op on this part (aside from sanding and polishing) is milling the “cooling” fins.

.125 end mill. .25 movement for each cut. I marked out the lines for the stopped cuts.



So there is your part for today and I’m at this step. Rotary valve tomorrow.

 
Can you elaborate on the 90 deg bevelling / chamferring endmill? that makes your nice 45 deg corners? Ive seen spotting drills & countersinks etc. in tool catalogs ground at 90 deg. Is that what it is? Or a purpose designed chamfering tool? Gotta get me some of those.

SS> I like to mill a bevel on plates. Cutting the edge against the fixed vise jaw makes everything work nicely with the bevels all around matching at the corners. Cut, turn 90 degrees, cut, turn, etc.

2013-10-25_170225.jpg
 
Stan,
Nice looking work with the usual top notch photo documentation. Did drilling that brass block in steps cause you any grief, or did you grind the rake off the end of your drills?

Cheers,
Phil
 
Phil
No grinding. Small diamond hone to "take the edge off". No problems.
 
Liney RV-1 - A New Double Wide

Part 3

The Rotary Valve


The O.D. of the valve is 1”. The closest 6061 round I have is 1.5” and, since the largest 5C collet is 1.125”, the 5C chuck had to come off and the 3 jaw replaced it. I actually have a custom 1.25” collet but that wasn’t a help here.



The 6061 round was chucked in the 3 jaw and turned down until it fit. Then the 5C chuck was put back on. With the small live center in place, the piece was turned to 1.00”



As I got close, I kept checking with the valve block until it just slid on



Next, 1” of each end is turned to .5” diameter. I first marked the length with a parting tool.



Again, when the DRO indicated that I was close, I began measuring. This is close enough.



Then the part was marked for the 1" length of the .5" O.D. section at the other end.



The valve is 4” in length and is to have a .25” hole from end to end. This directs air (or steam) to the cylinders. With no 4” long, .25” drill, I had to drill from both ends and have the hole meet in the center.
That’s what I love about the collets and the Set-Tru chuck. Take parts out, put them back, flip them end for end and it still is correct.



This is not the center drill from the previous photo. It’s the .25” bit in as far as it would go. I must have pulled it out 20 times to clear chips.



The part was reversed in the collet and drilled from the other end.



The holes met perfectly. This ¼” tube slipped right through.



Moving to the mill.

The final op was the cross drilled holes to meet the air passage. I found center and then the edge.



And then drilled until it met the passage.





The finished rotary valve.



The progress photo.



Hoping to get an early start on the cylinders tomorrow. The football game starts at 1:00. (That’s the one where the ball has pointy ends)
 
Stan,
I had to google liney rv1 to figure out what you are working on. Cute little engine.
Art
 
Liney RV-1 - A New Double Wide

Part 4

Cylinders


The cylinders ride on the rotary valve. In my 2X version, they start with a 6” brass square bar - 1”x1”.



Off to the bandsaw to cut the piece in half.



Once again, I had to dismount the 5C chuck. The largest square, 5C collet is .75”. The brass is 1”x1”.

Mounted the 4-jaw and clocked the piece in. My plan is to turn the round sections and drill and ream the cylinders for the pistons. At that point, the round part will fit in a 5C collet and I’ll change back to that.



Turned to somewhere near .95” but not a critical dimension as it’s the outside of the cylinder.



If I’m not turning into a shoulder, I would use the tangential toolholder with a round toolbit. This gives a beautiful finish. The finish is not so beautiful here but a bit of fettling (I was dying to get that in) and Scotchbite made it acceptable.





Drilling and reaming the cylinder bore, repeat the whole process for the other cylinder and that finishes the 4-jaw.





Moving to the mill to drill and ream the .5” hole for the rotary valve.



A nice slip fit. Repeat for the other cylinder.



When I was involved with “whistle-mania” a few weeks ago, I made the decorative cap with a carbide wood-router bit. I wanted to make the end of the cylinder round and another carbide router bit was put into a toolholder and did a nice job.





We now leave your regularly scheduled built log so I can watch the football game (remember, the ball with the pointy ends)



Game over.

The cylinder end is drilled and tapped for 6-40 set screws to hold the cylinder to the valve,



Two more parts to add. More polishing to eliminate the final tool marks will come.



Not quite looking like an engine but getting closer.



Pistons tomorrow. Stay tuned.
 
A wood router bit? Who'da thunk? Fantastic work Stan. I'm enjoying watching your progress because I have no idea what the finished engine looks like and the suspense is building

Cheers,
Phil
 
There was a question on modelenginemaker.com about the size of this engine. I thought I'd post this here, as well.

 
Liney RV-1 - A New Double Wide

Part 5

Pistons


Today's machine porn: the pistons.

The pistons are to fit in the .344 cylinder bore. Started with a stainless square bar; .375”
Initially, I took a cut with my Warner HSS tooling. and wasn’t completely happy with the finish.




I changed to this carbide tool with a really big radius and, with the lathe cranked up to about 1200 rpm, got a better result.



When I got close (.434) I slowly approached a nice fit for the piston. Make a cut, check the fit, move in a half thou, repeat. If I close off the valve hole with my thumb, the piston pops when removed and I can feel the suction. I’ll accept that as a good fit.



Then the usual sequence of spot drill, drill, ream and chamfer for the crank pin holes.





Two more parts in hand for scale.



Here’s where they fit.



Tomorrow, the cranks. Then a few simple bits and the flywheel. I’m thinking about a cast iron outer rim with a press-fit brass center, but that could change.
 
Liney RV-1 - A New Double Wide

Part 6

Flywheel


I was going to make the cranks, spacers and shafts today, but I needed some quality time with cast iron.
Big chunk here; a bit over 3” diameter.



I’d really hate to do this with a hacksaw.



Here’s my CoC with the Ballpoint Font.



Unbolted the step jaws and replaced them with my soft jaws. The spacer keeps tension on the jaws while I’m boring them. Since the soft jaws are bored in place, everything stays concentric and the part can be flipped to machine the other side without having to indicate anything. Since I started using these, no more wobbly flywheels. Less than 1 foot of 6061 and worth every penny.



I dug out the carbide tooling since I use my Warner indexable HSS and the tangential holder for damn near everything. Cast iron likes the carbide.



After facing and turning side one to diameter, I flipped the part and finished side 2.



Hogging out the center recess. I kept the depth to .200” to maintain the flywheel’s mass. Normally my flywheel webs are much thinner.

So that’s one side roughed out. Flip and repeat.



Since everything is concentric at this point, the part was drilled and bored to .249”
The .250 shaft will be a press fit.



Now to the Bridgeport to drill the decorative holes. After centering the flywheel with the Blake, I had the DRO do the pattern. Never trusting my “on the fly” dimensions, I ran thru the bolt hole circle and just touched off each one. Looks correct.



So off we go. Just turn the handles until the DRO reads zero, make the hole, display the next hole on the DRO and repeat.



Running through the hole pattern again for the chamfers.



Had some chatter at the outer edge of the web. The coarsest paper I had was 220 and removing the tool marks was taking forever. Ordered 60, 80 and 120 grit emery from McMaster to do the finishing,

Here it is with a size reference. 13oz (370gm).



Looks like one more day of machining to see if it’s a runner. Then finishing, fettling, polishing, and whatever else.

Try and remain calm, but no parts tomorrow. I have a bunch of things that must be done.
Look for the next installment on Thursday evening.
 
Looking Very Nice. I hope it is a good runner.

Cheers,

Tom
 
I built the RV-1 a few years ago and was thrilled to see it run the very 1st time !! Your 2X version is going to run very nicely. One change I should have done was to use a heavier flywheel, AL is just too light, brass or steel would have been better. Though it still runs like a champ ! Looks like you're using steel, so that I'd think will work very nicely !

Mike
 
Mike
Good old USA cast iron. As heavy as I could get.
 
Liney RV-1 - A New Double Wide

Part 7

Everything Else


I know you all missed having this captivating build log yesterday, so I did a major push today. All parts are made. Tomorrow: assembly, intake and exhaust port drilling and…

First the cranks. Brass round bar turned to size then drilled and reamed .251 for a sliding fit of the flywheel shaft. It will be held in position with 6-40 setscrews.



Parted off both cranks then it’s off to the mill.



I switched to a v-jaw on the vise and then indicated center.



The second hole for the crank pin was spot drilled, drilled and reamed .249 for a press fit.





Next, the cranks were smoothed out with the face mill.



I placed the cranks upright in the vise and used a 1-2-3 block to align the two holes, close-enough, to vertical. At one point, I was going to make a fixture with flat sides and dowel pins which would slip into the holes. I’d then chuck up the DTI to adjust for a vertical orientation. Never happened. Close-enough here won’t impact the operation of the engine.



After finding the centerline, I used a .50” ball end mill to remove what shouldn’t be there.





Quality time with Oliver to smooth out tool marks and to round over the sharp corners.



Two more parts for the “finished” box.



Next, two aluminum spacers, 1.25” diameter. These slip on the rotary valve between the valve block and the cylinders.



After drilling and reaming to .501”, both spacers are parted off.



Since the bearing towers are .5” wide and the bearings are .25” wide, I needed a filler to take up the space. I turned these to .001” over the I.D. of the ring. The center hole is .015” oversize so there isn’t any chance of interference with the shaft. When I looked at this picture, I realized that I need to do more fettling to blend the ring with the base.



Here’s the filler ready to press in.



And pressed.



The housing, flipped over with the bearing ready to go under the press. Anxious to see how these acetal bearings work out. They are supposed to be “No-lube” under 2500 RPM.



Two more for the “finished” box.



The cranks after sanding and polishing. The hole being done here will be for the 6-40 setscrew to affix the crank to the shaft.



Family portrait of all parts.



The shafts, after press fitting. Tomorrow, I’ll assemble everything and drill the intake and exhaust ports in situ.

Then, get some air in it and see if it’s a runner.

 

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