# Another Rupnow Air Hit n Miss Engine



## bmac2 (Jan 6, 2014)

Though Im tempted to build a Solar Wind Turbine Biomass Gasified Powered Brine Pump or whatever that stuff is on the homepage. 
I feel like Im the only one that hasnt built Brian Rupnow's Hit n Miss Version of Chuck Fellows "Horizontal Single". 
This will be engine No.6 for me so first let me impart upon you my vast knowledge of hit and miss engines . . .
I like them . . . . . and I think there cool. . . . . This could be a long build


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## bmac2 (Jan 6, 2014)

Looking over the plans and Brians excellent build log I should be able to pull it off. As usual All good things start with a 4x6 Band saw. To those of you who enjoy this hobby without one I salute you. Mine is a fourth hand dumpster dive I got for free and needed a lot of love and a little welding to get it to where it is today, cutting relatively straight and it hardly throwing the blade any more. But without it Id be collecting stamps.

I dont have any 1 1/4 stock so Ill flip the page to Metal Butchers Chucks single and make the base, frame sides, and front from 1/4'' thick aluminum with 4-40 screws.


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## bmac2 (Jan 6, 2014)

The cylinder is 1 ¼ mystery metal. And Im going to building up the flywheels.


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## bmac2 (Jan 6, 2014)

Cleaned up the two blanks for the sides and when Krazy glue them tougher before laying them out and milling them to the final dimensions.


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## bmac2 (Jan 6, 2014)

I decided to try doing the cylinder in the mill. Turned out to be a bad idea, the bore turned out fine but it took me over an hour to get it trued up in the lathe to cut the shoulder.


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## Brian Rupnow (Jan 6, 2014)

Although I would like to take credit for that engine, I can not. It was designed by Chuck Fellows, and he is the true originator of this marvelous little engine. I wanted to build Chuck's engine, but had to draw it up in Solidworks and create drawings to work to. So--Thank me for all the pretty drawings, but please, give credit to Chuck Fellows. He is the true genius behind this engine.---Brian Rupnow


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## bmac2 (Jan 6, 2014)

Hi Brian
This is definitely Chucks engine. I think Chuck Fellows is the engine whisperer or something. Im just going for the 2 stroke version chickening out on the gears, and want to give the hit and miss a try which I thought was your addition. 
I hope I can do justice on both of your efforts


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## bmac2 (Jan 6, 2014)

Damn the weather is bad everywhere. At times like this I just close my eyes and say at least Im not in Winnipeg (-50 yesterday with the wind chill)
On with the build. I decided to go with a built up the crank with Loctite and pins. Let it sit overnight and cleaned it up on the mill.


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## bmac2 (Jan 6, 2014)

Im going to try Brians trick with the piston and start with a piece of 1 x 1 aluminum.


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## bmac2 (Jan 6, 2014)

Yep. That square end sure comes in handy once its moved to the mill.
Center it up and done. That is one fast setup.


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## bmac2 (Jan 6, 2014)

The bearing blocks are simply brass sized per the drawings, and I drilled them in place with witness marks on the inside. Once all the holes are tap and the blocks are bolted down I dialed it in on the lathe to drill/ream the holes. I picked up a couple of sets of feeler gauges from Busy Bee Tools a while back for a couple bucks each and use them as shims when I just have to have that extra little bit to get things on the center line in the lathe.


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## bmac2 (Jan 7, 2014)

Wanted to try for a classic I beam style for the con rod because this is the first engine Ive built with a rod big enough it try it on. 
After drilling the holes for the screws and adding witness marks I split the blank


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## bmac2 (Jan 7, 2014)

Once taped and screwed together started to rough out the shape


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## bmac2 (Jan 7, 2014)

With a piece of 1/8 in the small end and another in the ¼ hole in the big end to set the angle I milled it down to the final width.


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## bmac2 (Jan 7, 2014)

Now. To round off the small end I saw this method on http://www.modelenginenews.org/index.html (Making Conrods, Made Easy) and decided to give it a try


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## bmac2 (Jan 7, 2014)

Ok. Milling cutter intact, conrod intact, and no blood. Ill call that a success.


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## bmac2 (Jan 7, 2014)

Oiled Up the bits so far and let them running In


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## Swifty (Jan 7, 2014)

I'm following along Bob, just watch out for your fingers if you are rotating that rod by hand. Cutters are prone to grab and not very forgiving.

Paul.


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## bmac2 (Jan 7, 2014)

I hear ya Paul. If that rod had been less than 3 I never would have tried it. It would pull a bit on one side then push when cutting the other. Once centered it was pretty much neutral but no replacement for a part *solidly bolted down* to my rotary table.


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## bmac2 (Jan 8, 2014)

So its time to start the head . . . I cut out the blank and cleaned it up . . . But Im not sure I like it. It just looks too big. When I was looking for another engine to build I snagged a bunch of pics of engine (I know. I leach) and remember seeing this. Tried to find it again but despite the search engines valiant efforts I gave up but I think once again it came from that deep mind of Mr. Fellows.


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## bmac2 (Jan 8, 2014)

So no chips just burn up the electrons in the old CAD. To my very limited experience this should/could work. I think it might be more to scale with the rest of the engine and I could run the airline out the back.


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## bmac2 (Jan 9, 2014)

Looks like Ive got a decent stash of 1 1/4 cold rolled so a quick trip out to the garage to cut off the blank for the head. Cold out there, the 4x6 didnt sound happy with me. Cleaned up both ends of the blank and got it to the right size in the lathe


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## bmac2 (Jan 9, 2014)

Pin pointed off the edge to establish a 0,0 reference for the iGaging DROs. I know, these things are not perfect but they beat the crap out of the ½ turn of slack I get out of the hand wheels on my Mini Mill and I did the X and Y axis for under $100.00


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## bmac2 (Jan 9, 2014)

Was going to have the bracket as a bolt on but thought if I made it part of the head with a small (.10) shoulder I would have a good vertical reference. Roughed out bracket and milled the 1/8 slot for the rocker arm then spotted the locations for the bolt holes


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## bmac2 (Jan 9, 2014)

With the head drilled and counter sunk I used it as a drilling jig for the cylinder.


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## bmac2 (Jan 9, 2014)

Used that nice .10 shoulder to help set the head up vertically for drilling and as I still had the 1/8 in mill in I spot the center for the ¼ hole for the valves.


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## bmac2 (Jan 9, 2014)

Bobs tip of the day. Ok you experienced guys can skip on to the next part. This is for us rookies. Im paranoid after drilling a nice hole on the table on my drill press while step drilling. Id set the depth stop but didnt take into account that as I went up in drill size they get _longer_. So with the set up for this piece I know I have 1 ¼ inches of material set 1/2 inch (tool blank) off the bottom of my vice for a total of 1 3/4 inches. I set the bit so its just above the work piece and used a 1 3/8 parallel to set the depth stop on the mill. Repeat with all the bits and I have a nicely reamed ¼ in hole in the head and no damage to my vise.


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## bmac2 (Jan 9, 2014)

Milled a 3/8 in flat top and bottom of the head for the intake and exhaust, drilled and tapped the 4 holes and it's done. I think with that shoulder it me longer to type this than it did to make the head.


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## bmac2 (Jan 9, 2014)

If you are looking for small taps I cant say enough about these Sowa spiral taps. Ive only broken 1 and that was because I was stupid and trying to use it free hand in some gummy brass. Nothing is more reassuring than seeing long (relative to a 2-56 tap) curly shaving coming up out of the hole.


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## cfellows (Jan 9, 2014)

Bob, the drawing you have in response #21 should work OK.  The other drawing you showed was mine, but I'm not the originator of that valve actuating mechanism.  I first saw that design in the 5 cylinder radial engine, the Liney Halo.  I used it on this engine:

http://www.homemodelenginemachinist.com/f43/anzani-3-cylinder-radial-compressed-air-13574/

But I later changed it to a rotary tube valve arrangement.

Chuck


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## bmac2 (Jan 9, 2014)

Hi Chuck. Glad to see youre vertical again and thanks for the encouragement. 
Thank you Mr. Liney Halo. Hope I dont mess up your design.
Im way more comfortable working directly from plans than winging it on my own. Let Captain Kirk go where no man has gone before I like drawings.  Your Inverted Compressed Air Hit n Miss sounds great. To my uneducated eye the governor arrangement looks a lot more like what Ive seen on real (if thats right word) engines. One of these days Im going to have to man up and give gear cutting a go.


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## bmac2 (Jan 10, 2014)

The valve seat is just 1/4brass ¼ long. I havent a clue if the angle would matter a lot so I just used a ¼ center drill as I find they drill clean with a not bad finish.


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## bmac2 (Jan 10, 2014)

The ball for the valve is .184 stainless steel salvaged from a small pump type hand sanitizer. 
http://www.homemodelenginemachinist.com/f25/free-stuff-21757/


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## bmac2 (Jan 10, 2014)

With the valve seat krazy glued down and the ball hot glued to a specific rod (the rod has to be long enough to hold, be stiff enough, and most importantly be within reach without having to get off my chair) I honed it in.


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## bmac2 (Jan 10, 2014)

Aaaa.:wall: The pin I want to use for the valve rod (?) is hardened stainless steel out of an old hard drive measuring .0377. Id milled a 1/8 hole .10 down in the center of the head to reduce the amount of steel I need to drill through with that little #62 drill bit. Unfortunately the hole doesnt go in the center but worked out to be just south of that. The 2 holes dont overlap (barely) so I just filled in the hole with some JB weld. I think it will be ok


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## bmac2 (Jan 10, 2014)

When I tested the seal I couldnt hear any leaking from the ball but it was leaking around intake manifold. Used some copper tape to make a gasket under it and cant hear any air escaping with 10lbs on the intake.


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## bmac2 (Jan 10, 2014)

The internal parts done its time to set it aside and start on the flywheels.
I hate flywheels.


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## bmac2 (Jan 10, 2014)

Chilly In the Garage. Ill have to let the old 4x6 free run for a while to warm things up.


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## bmac2 (Jan 10, 2014)

Back in the warm basement, the blanks for the outer rims have been cleaned up.


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## bmac2 (Jan 11, 2014)

Going to try for a spoked flywheel using aluminum. Its just over 8th of an inch thick but I cant see where thickness is critical. Krazy glued and bolted the 2 blanks tougher and took the outside dimension down to size then bored the ¾ hole in the center. The copper strips are to protect the aluminum from the jaws.


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## bmac2 (Jan 11, 2014)

This is the spoke pattern I came up with. Used a center drill to mark out the corners. That is some soft aluminum, no wonder I got it for free. Have to see how this is going to come out.
Drift off topic here for just a minute. In the picture you can see Ive taken the battery out of my Chinese calipers. I was lucky if I got a month out of a battery whether I was using it a lot or it just sat in the drawer. Checking on the internet I found out that with some of these cheaper calipers, when you turn them off all that does is turn off the display. A quick check for this is to open the jaws, turn the unit off, move the jaws and turn it back on. If the display shows the new reading its only the display thats shut off with the switch. By removing the battery at the end of the day Im getting about 6 months or better out of a battery. Im going to save up my birthday money and one day get a good one.


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## bmac2 (Jan 11, 2014)

_LET THE CHIPS FLY_! 
Oh. That looked a little rough.


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## bmac2 (Jan 11, 2014)

Separated the 2 parts with some heat and cleaned up they dont look bad at all.
15 1/4 oz each. Heavy?


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## bmac2 (Jan 11, 2014)

In for a penny in for a pound I guess. On to the hub for the governor flywheel. 
The hub is ¾ so I used parallels to scribe a center line and locate the 2 holes for the backing plate.


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## bmac2 (Jan 11, 2014)

Not knowing any better a few years ago I bought one of these sets of things that looked a lot like drill bits but make funny triangle shaped holes of odd sizes. The numbers marked on the box are a little confusing because they dont relate to the drill thing in that position. They do make good setup pins. In this set #32 to #36 measure the same size so Im using 2 of them to setup the hub to mill the clearance slot for the weight arms.


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## bmac2 (Jan 11, 2014)

Used the lathe to align the parts and press them tougher with Loctite and Ill put on a fillet of JB weld epoxy after everything sets up.


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## motoseeya (Jan 11, 2014)

Nice very nice. You do gooood work. I hate fly wheels too lathe to small:rant: but I keep at it maybe someday.;D


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## bmac2 (Jan 11, 2014)

Motoseya youre too kind. I think the secret to having stuff look good is to have the camera just slightly out of focus. I know on the lathe a lot of the time Im using the tool thats easiest to set up but not necessarily the right tool. If/when I get this thing running Im going to hit the books.
If you want to see some BEAUTIFULL work on small equipment checkout Davewilds Linford two stroke build.

http://www.homemodelenginemachinist.com/f31/linford-two-stroke-21643/


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## barnesrickw (Jan 11, 2014)

They used to use that out of focus technique on Cybill Shepard.


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## bmac2 (Jan 11, 2014)

The Sliding Cam and Actuator Bushing. 
I must say this is the part that I have been dreading. The notch in the sliding cam is a very close fit for the actuator, and the two parts have to align correctly on the ¼ shaft.


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## bmac2 (Jan 11, 2014)

Making the blanks was not a big deal as both are ½ so to drill and ream the hole. Cut the steps in the actuator. Cut the grove in the sliding cam and parted them off.


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## bmac2 (Jan 11, 2014)

Its time to close my eyes and tell myself to trust the math. Actuator Bushing
Part OD = .563
Finished size = .375
Difference = .094 on each side
With the actuator bushing on a parallel in the vice I set the Z axis dial indicator to 0.


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## bmac2 (Jan 11, 2014)

Milled off .094


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## bmac2 (Jan 11, 2014)

Flipped the part over and repeat


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## bmac2 (Jan 11, 2014)

I love it when the math works


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## bmac2 (Jan 12, 2014)

The Sliding Cam. Used my home made edge finder to Pin pointed off the edge to establish 0, 0 then used the DRO to find center and milled the .375 x 0.1 notch.


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## bmac2 (Jan 12, 2014)

I cant believe it but I just had to deburr and cleaned them up and they fit!


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## bmac2 (Jan 12, 2014)

After reading Brian Rupnows build log Im not going to bother with the 0-80 cap head screws. I live in oil country and my _Screw Guy_ looks at me funny when I ask for things under ¾ inches. I going to make a small pin the same diameter as the head on a 0-80 cap screw and Loctite it into place. This way I get two of my _favorite_ things all in one part. Stainless Steel and tiny parts.


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## bmac2 (Jan 12, 2014)

Theres enough meat on the actuator so Im going to use a 2-56 set screw 
Somewhere theres dictionary that shows:
*irony*
i·ro·ny
noun: 
The expression of one's meaning by using language that normally signifies the opposite, typically for humorous or emphatic effect.
E.g. The only 2-56 set screws available are 5/8 of an inch long

Oh well its easier to cut them than make them


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## bmac2 (Jan 12, 2014)

Disaster. :fan: Went to punch the spot for that wonderful SS pin and didnt think to support the grove. This bent the side down and when I tried to straighten it out it snapped.


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## bmac2 (Jan 12, 2014)

Disaster averted. I still had the ½ stock in the lathe and the Y axis on the Mill was still locked so it was a quick recovery for my broken part and it fits just as nicely as the first one.


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## bmac2 (Jan 12, 2014)

The reason for the ring around some of the pictures is that my camera doesnt handle close-ups very well.
This is my _Rube Goldberg_ setup for extreme close ups.


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## bmac2 (Jan 12, 2014)

The notch for the rocker arm turned out not to be deep enough so I had to set it up (hate having to do that) and take it down another 0.10.


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## bmac2 (Jan 12, 2014)

For the rocker arm itself I know the basic size it has to be, so Im purely winging it as to the final shape. I inserted a .125 stainless steel ball where it contacts the valve rod and just trimmed the angles until it looked right


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## bmac2 (Jan 12, 2014)

The valve actuator fork is a simple milling job done as per the drawing.


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## bmac2 (Jan 13, 2014)

The push rod is just 1/8 drill rod threaded 5-40 on one end. Once attached to the fork I marked it for length and rounded off the end.


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## bmac2 (Jan 13, 2014)

I'm starting to get antsy. For the valve rod guide I just worked from a quick penile sketch and whittled it out of some ½ by ¼ brass. Ill say it again I love those Sowa Spiral Taps


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## bmac2 (Jan 13, 2014)

All of my engines up to now, have been made by following known working plans, drawn up by people that knew what they were doing. Any changes I made where cosmetic at best. Ive been feeling apprehensive on this one ever since I decided go swap the cylinder head and valve assembly. Normally Im a pretty patent guy. But normally I dont deviate this far afield from the plans. 
I partially assembled _most_ of the bits and pieces Ive finished so far. The sliding cam and actuator are held in place by the governor spring, a washer and a plastic cable tie. Its dripping with run in oil and the flywheel needs to be trued up but.scratch.gif


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## bmac2 (Jan 13, 2014)

ITS ALIVE! 
Ok. Im going to try and post a video. The quality is not very good. I just used my digital camera. 
This might be the first _Chuck Fellows Horizontal Single with a Liney Halo designed Valve_
I still have work to do, but now I know Im not just working on a paper weight.

http://s775.photobucket.com/user/bmac6129/media/HMEM%20Stuff/102ChuckFellowsHorizontalSingleWithaLineyHaloValvemovfile_zpsa4b6ee88.mp4.html?sort=3&o=0


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## bmac2 (Jan 13, 2014)

Hum. Ok Does anyone know how to post videos? ???


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## cfellows (Jan 13, 2014)

Bob, I've never tried uploading videos to photobucket, so someone else will need to chime in here.  I always use youtube.

 The engine looks great.  I suspect you better get the drawings in order because a lot of people are going to want to build it!  

 Chuck


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## Brian Rupnow (Jan 13, 2014)

Posting a movie on Photobucket
Go to www.photobucket.com and open a free account.
Make a movie with your video camera---it will save it as an mp4 file
Download the mp4 file to somewhere on your computer that you can find it.  Name it if you want to.
Find it on your computer. Dont open it. Right click on it and choose copy
Open windows Live Movie Maker and right click once in the rectangular black area, then right click on the clipboard at the top of the screen that says paste---Your movie will appear as a number of still shots, but not run.
In top left corner of Windows Live Movie Maker there is a white thing with writing on it that looks like a book with a white triangle beside it. Click on the white triangle, and a number of options will appear. As soon as you put your cursor over save Movie it will give a bunch of options.
Choose Windows Phone Small----This will open a new screen with an area coloured blue that says My Movie.WMV---Start typing in a new name for your movie while the blue is still hi-lighted and the text will change to whatever you want to call it. My Sawmill works.
Up at the top of the page select what directory you want the movie to appear in and it will save as a .wmv file, which Photobucket can upload.
When you go to close down Windows Live Movie Maker it will ask if you want to save your movie. Say No---Youve already saved it. Open your Photobucket account, choose upload, and guide it to where your My Sawmill .wmv is filed.
When your movie is finished uploading (it takes a while). Click in the box that says IMG code the box should turn yellow and tell you it has been copied. Go to the forum, start a post, hold down Ctrl on the keyboard with your left hand and press the v on your keyboard one time. There---You have posted a link that others can click on to see your video.----Brian Rupnow


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## bmac2 (Jan 13, 2014)

Hi Brian 
I'd uploaded the vid to Photo Bucket but in the stock .mov format Kodak uses. I'll try again.

Thank you . . . .


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## motoseeya (Jan 13, 2014)

ok brian I don't have enough brain cells to comprehend what you sead much less how you done it . I only have one brain cell left and I don't want to tax it to much I stll have to breathe and some times I think that is to much:big::big::big:


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## bmac2 (Jan 13, 2014)

The video - second try


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## bmac2 (Jan 13, 2014)

Brian. good on ya! Thm:
This is Definitely one of those Copy / Paste / Save for future reference moments. 
In Photo Bucket I think was picking up the HTML Embed link from the Albums page not the page with the IMG link. I didnt have to change the format.


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## bmac2 (Jan 14, 2014)

Cant remember the last time I spent this much time in the shop. Its ok. I have a note from my wife that says this January I can spend as much time in the dungeon as I want. But I think I get to paint the kitchen as soon as Im done. She brings me food and is making sure I stay hydrated.
The Backing Plate. Like Brian in his build log I went for milling it out one piece rather than soldering it up. Used aluminum instead of brass mainly because its what I had. Got the blank down to size in the lathe and marked center with a ½ parallel. Brought it down 0.2 leaving the 3/16 ridge down the middle for the weight arms hinge points.


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## bmac2 (Jan 14, 2014)

Cleaned out the middle leaving .175 on each end and plunge cut the 3/8&#8221; hole.


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## bmac2 (Jan 14, 2014)

There is nothing like a 1/16 end mill to help me relax. I can hear that little ping as it snaps already. Light cuts, lots of oil and keeping it clean of buildup seem to be the best way to use these little guys. Used the end mill to spot the locations for the two 4-40 screws


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## bmac2 (Jan 14, 2014)

With a 1/16 slot and a 1/16 blade on my square setting it up to finish the slots went quick. Once again Light cuts, lots of oil and keeping it clean of buildup did the trick and no ping.


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## bmac2 (Jan 14, 2014)

Drilled the holes for the two hinge points. This time making sure I supported them with shims. I do not want to make this part again.


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## GailInNM (Jan 14, 2014)

Fine work Bob.  Runs like a charm.
Gail in NM


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## barnesrickw (Jan 14, 2014)

Nice looking engine.


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## cfellows (Jan 15, 2014)

Run's good, Bob.  Are you planning to run it on full compressor pressure, like 100 PSI?

Chuck


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## bmac2 (Jan 15, 2014)

In the video its running at around 20-25 lbs. I use a portable air tank in the basement and the gauge is not terribly accurate. When I increase the pressure it accelerates smoothly until it hits about 45-50 lbs. Then it starts having an asthma attack and jumping all over the bench. Would this be the spring on the exhaust valve? Right now its just one out of my small DrawerO-Springs and Id rate it at medium to light. The other thing Ive been thinking about is the flywheels. Their just under 1 lb. each. Would lighter be better?


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## cfellows (Jan 15, 2014)

bmac2 said:


> In the video its running at around 20-25 lbs. I use a portable air tank in the basement and the gauge is not terribly accurate. When I increase the pressure it accelerates smoothly until it hits about 45-50 lbs. Then it starts having an asthma attack and jumping all over the bench. Would this be the spring on the exhaust valve? Right now its just one out of my small DrawerO-Springs and Id rate it at medium to light. The other thing Ive been thinking about is the flywheels. Their just under 1 lb. each. Would lighter be better?


 
 Bob, I think the flywheels are fine as is, especially if you want the engine to run fairly slowly.  

 You can't run the engine on full air pressure without the governor, but once it's installed and running in hit n miss mode, you'll want the air pressure as high as you can get it to maximize the number of revolutions between "hits".  You may have to experiment with a stronger valve spring to get it to run the way you want.

 Chuck


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## bmac2 (Jan 17, 2014)

Started working on the governor arms and weights. In the plans it is noted that the weight arms are File to fit. These reminded me of doing finish carpentry. A lot of it is Fit and Fiddle. Cut it to size and then fiddle with it until it fits.


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## bmac2 (Jan 17, 2014)

Cut out the blank and plunge cut the ¼ hole in the center.


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## bmac2 (Jan 17, 2014)

I like my Craftex Mini Mill and though it was third hand when I got it, its serves my needs. That being said I think the buyers with Busy Bee Tools must have found a really good restaurant on the day everyone was picking paint colors. Black, Green, and Cannery Yellow must have been all that was left.


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## bmac2 (Jan 17, 2014)

Made a quick mandrel to hold the blank on the rotary table.


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## bmac2 (Jan 17, 2014)

The mandrel doesnt go right through the blank so I could use the end mill to align the rotary table and round off the ends.


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## bmac2 (Jan 17, 2014)

Used a small square to set it up in the mill to split the two weights.


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## bmac2 (Jan 17, 2014)

Its warming up again so tomorrow Ill be able to get out to the garage and solder them up.


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## bmac2 (Jan 19, 2014)

I was tempted to soft solder the weight arms. But I need the practice silver soldering and it looks like all the reading Ive done lately has not gone to waist. One of the biggest challenges I have with silver soldering small parts is having the torch blow them out of alignment.


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## bmac2 (Jan 19, 2014)

Cleaned up and still square even after having the buffing wheel throw it across the shop at a truly amazing speed. Note to self time to replace the gloves for the buffer


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## bmac2 (Jan 19, 2014)

The pivot pins for the weight arms are cut from the shank of a dull 1/16 drill bit. I dont sharpen anything under 1/8, its too easy to just replace them. I just put them in a drawer marked Dull / Bent and use them when I need a pin.


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## bmac2 (Jan 19, 2014)

AAARG !
I had everything fitted up so off to the garage so I can use the compressor. The governor seems to be working but intermittently. Something is sticking when they start to open.
It was while I was dumping oil on everything and fiddling around that I managed to bash the rocker arm and bend the valve pin. Messed around with it for a couple of minutes before I thought, Its only a pin. Make a new one.


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## bmac2 (Jan 19, 2014)

When I cut small pins or screws with a Dremel I like to hold one end in a small vise and the other in a pair of hemostats. Makes it a lot easier to find both pieces.


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## bmac2 (Jan 19, 2014)

The governor reinstalled and now its down to tuning everything and running it in. Other than that, a good cleaning, some body work on the flywheels and some paint.
Ill do that tomorrow. Its nice day outside and I havent taken down the Christmas Lights.


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## cfellows (Jan 20, 2014)

Nice, Bob, I'm anxious to hear it running in Hit n Miss mode.

 Chuck


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## bmac2 (Jan 20, 2014)

Hi Chuck
Well its running, and it hits, and it misses. . . . What its doing is about a 3 second run at high revs (I dont have a tach) before the governor kicks in, then free spins for around 5 seconds dropping almost to a stop before the governor drops out. Everything _appears_ to be moving smoothly with no binding. Having the governor kicking in late to me would be either the spring it too strong or the weights are too light. But wouldnt it be the reverse for free running too long? 
I was going to start to experiment with adding weight to the arms to get them to kick out at lower rpm.
Heaver weights and a stronger return spring?


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## cfellows (Jan 20, 2014)

Seems to me there is something else going on.  From your description, it sounds like the governor is having trouble engaging the cam.  I suspect that the strong spring is making it rev pretty high, but the governor is having trouble engaging the cam when it slows down.  I would suggest a weaker spring and maybe introducing more clearance on the cam engaging mechanism.

Are you running at maximum air pressure from your compressor?  When the engine does hit, it needs to get a pretty good boost from the air source.

Chuck


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## gus (Jan 21, 2014)

Hi Bob,

Congrats. You got the H&M going. 

Taking a diversion break & building a 80mm RT..RT is straight forward project and very forgiving
if I goofed.


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## Brian Rupnow (Jan 21, 2014)

I like your hemostat idea. I wrap a piece of masking tape around the cut off end and then it doesn't fly across into the parallel universe never to be seen again. They get too hot to just hang onto with bare fingers.---Brian


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## bmac2 (Jan 21, 2014)

Brian Rupnow said:


> I like your hemostat idea. I wrap a piece of masking tape around the cut off end and then it doesn't fly across into the parallel universe never to be seen again. They get too hot to just hang onto with bare fingers.---Brian


 
Thanks guys
I think that when we set up machinery in a room, something about the placement/mass/ magnetic field causes an intermittent vortex into another dimension to open. In my last _Mensa_ _Moment_ I was doing an autopsy on the head after bending the valve pin. The oil on the slave exhaust valve wouldnt let it slide out. Then that little Murphy's Law voice in my head said _I know. Ill just give it a little air_ . . . . . Its a simple piece. Only took a couple of minutes to make a new one. 
Im going to disassemble the governor and give everything a close look tonight.


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## motoseeya (Jan 21, 2014)

That is a very nice engine you have their. I think I would like to try one I like air engines ic engines are to much $$$ for elec. parts for a model that will only run 1 or 2 times and then just look at. And this is not your first rodeo I think . Very nice work.


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## Brian Rupnow (Jan 21, 2014)

Motoseeya--The electrics for a points style ignition which include points, condenser, and coil cost about $75 IF---you have a battery all ready.


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## bmac2 (Jan 22, 2014)

cfellows said:


> Seems to me there is something else going on. From your description, it sounds like the governor is having trouble engaging the cam. I suspect that the strong spring is making it rev pretty high, but the governor is having trouble engaging the cam when it slows down. I would suggest a weaker spring and maybe introducing more clearance on the cam engaging mechanism.
> 
> Are you running at maximum air pressure from your compressor? When the engine does hit, it needs to get a pretty good boost from the air source.
> 
> Chuck


 
Chuck! . . You where spot on Thm:. Thank you 
Took a methodical approach to this, with a lot of disassembly/assembly going on. Used Brians trick from his build log and mounted the governor flywheel to a short shaft held in a cordless drill. Cleaned up and refitted the components trying one thing at a time. It reminded me of installing an old-school internal modem. Set the IRQ /DMA dip switches, install, boot up, and repeat.

In the end I think what made the difference was a small rough spot on the crank where the sliding cam rode. I polished it out with some emery. And reducing the return spring pressure.

Its too cold in the garage to run the compressor today so I used the portable air tank in the shop. It wasnt toped up but I gave it a try. Im quite happy with the duty cycle and in the video its running on about 30lbs pressure. I still have to true up the flywheels, and it might be a while before I can paint it, but for me this video is 43 seconds of pure joy. I could watch this all day . . . . . apparently for my wife. Once is enough.
:redface2: Arrrgh. . . Photo Bucket is currently conducting some _unplanned_ maintenance. Didnt the Titanic experience some unplanned maintenance? Ill try to get the video up later.


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## cfellows (Jan 22, 2014)

bmac2 said:


> Chuck! . . You where spot on Thm:. Thank you
> Took a methodical approach to this, with a lot of disassembly/assembly going on. Used Brians trick from his build log and mounted the governor flywheel to a short shaft held in a cordless drill. Cleaned up and refitted the components trying one thing at a time. It reminded me of installing an old-school internal modem. Set the IRQ /DMA dip switches, install, boot up, and repeat.
> 
> In the end I think what made the difference was a small rough spot on the crank where the sliding cam rode. I polished it out with some emery. And reducing the return spring pressure.
> ...


 
 Glad you got it sorted, Bob.  It's always a joy when things come together.  Looking forward to the video...

 Chuck


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## bmac2 (Jan 22, 2014)

Forget it. Photo Bucket has been down for more than 24 hours. The guy they sent to Radio Shack for parts must be on a bicycle without a light. Faster to just set up a YouTube account.
I have to think that after a couple of oscillating engines, and working from Brians plans, this would be an excellent build for people new to the hobby, especially if it was built without the governor. The machining is straight forward and relatively forgiving. The parts are small enough to be done on a small lathe, yet large enough to work with comfortably. The milling operations could be done in a 4 jaw, or with careful setup, clamped to the cross slide, or just filed. Chuck, thank you for an excellent design. Brian, thank you for all your work putting the drawings together. This was a fun build.

The _Chuck Fellows Horizontal Single with a Liney Halo Valve and hit and miss governor. _Now thats a handle. 

[ame="http://youtu.be/MCBzBgPmtik"]http://youtu.be/MCBzBgPmtik[/ame]


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## Heffalump (Jan 23, 2014)

Wow such a great sound! I do love a hit and miss.


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## wagnmkr (Jan 23, 2014)

Excellent Job!!!  I also love the sound!

It looks well finished, and I agree that it is fun to watch it.

That one is on the to do list for sure.

Thanks for the show.

Cheers,

Tom


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## Brian Rupnow (Jan 23, 2014)

Well Done--Excellent build documentation and results,---Brian Rupnow


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## bmac2 (Jan 23, 2014)

Hi Gus. Thanks
Thats something Ive been thinking of myself. I have a Craftex CT133 mini mill, same as the Grizzly and Harbor Freight machines. It can be a challenge finding stuff that isnt either bigger or costs more than the machine itself.


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## cfellows (Jan 23, 2014)

Nice build, Bob.  The engine runs good, but it sounds like the air flow is a bit restricted when it's freewheeling plus it seems like it should coast longer between "hits".  Are you sure the slave valve is completely clearing the port into the cylinder during the exhaust cycles?  You might try substituting a loose fitting ball bearing for the piston style slave valve.  They seem to work a little smoother and don't require as much travel when moving from one side of the cylinder port to the other.


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## bmac2 (Jan 23, 2014)

Ya. It&#8217;s a little weesey. The hole at the bottom of that &#8220;stack&#8221; is only 1/8&#8221; and now that it&#8217;s running I&#8217;m going to open it up. I haven&#8217;t had a chance to try it on full pressure yet. The compressor isn&#8217;t happy under 0 celsius. Once I get it running above 30 lbs. I think the freewheeling will improve. The governor was still kicking in until the tank dropped below 15 lbs. Just stops at 5.


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