Compressed Air V8 Cirrus

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I'm impressed. I haven't had much luck bending small diameter tubing. I'll have to try your approach!
 
Thanks Todd, Brian, Don...

Did some more work on the air inlet tubes today. I made the flanges that will be soldered to each tube.

I first chucked a length of 7/16" brass rod in the lathe and center drilled a 3/32" hole about an inch deep. Than I used a parting tool to part off 9 disks, each .080" thick. I made an extra one since I usually manage to screw up at least one. :Doh:

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After running each face over some 220 grit sandpaper to remove the flashing I clamped each one individually in my milling vice and milled opposing flats, resulting in a piece 1/4" wide and 7/16 long.

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Got one piece in the picture mocked up with the air tube sitting in the flange. When soldered, the top end of the tube will extend through the flange by about 3/32" and extend into the head by that amount.

Next I'll drill the holes on either side of the center hole. These will be used to screw the flange to the cylinder head.

Chuck
 
Chuck, nice work and interesting detail as usual from you. I like your tubing bending fixture.

Regards,

Chuck Kuhn

Thanks, Chuck

That tubing bender does work nice. You might pay particular attention to the little block that fits between the spool and the vice jaw. I purposefull made it that size so it would be a firm fit... Didn't want to have to permanently fix it to the jig.

Got some more work done on the engine today. I had kind of convinced myself not to make an oil pan for the crankcase, that I would just leave it open. I like looking at the crank and rods and it also makes it easy to oil them periodically. However, I decided the engine would look better if it had a pan, so today I got to work and made one.

I started off with a piece of 3/4" thick magnesium 3 inches long and 1.7" wide.

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Here I've milled 3/16" of each side to form the bolt flanges for the screws which will attach the pan to the upper crankcase half.

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Next I milled out the inside of the pan and rounded the inside edges along the sides.

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Finally I rounded over the outside bottom edges.

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And here's a picture of the two halves placed together.

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Chuck
 
Chuck, how did you keep those brass pieces in the hex socket? Ive always found sockets to be a bit over the stated size. Ive tried to stick bolts in them as a holder to reach down into tight places, but never found anything that held well enough to work, but then would release the part.
 
Great work Chuck, love the pan. How will you mount it, will you be putting feet on the pan? I also liked you bending jig, but I use glass beads in the tubing just in case.

Don
 
Chuck

I haven't been saying much but thought that I better let you know that I am watching your progress. I like some of the ideas that you have came up with to solve some of the problems that have came up. You are doing an excellent job. Thanks for continuing to share it with us.

Cheers :)

Don
 
Chuck, how did you keep those brass pieces in the hex socket? Ive always found sockets to be a bit over the stated size. Ive tried to stick bolts in them as a holder to reach down into tight places, but never found anything that held well enough to work, but then would release the part.

Hi Ron,

The socket I used actually had a pretty close fit with the hex rod. And, of course, the drill bit was pressing the hex rod into the socket against a shouldered down diameter inside. I think rather than sockets typically being oversized, that nuts and bolts tend to be a little bit under-sized. Maybe I just got luck on this one..

Chuck
 
Chuck

I haven't been saying much but thought that I better let you know that I am watching your progress. I like some of the ideas that you have came up with to solve some of the problems that have came up. You are doing an excellent job. Thanks for continuing to share it with us.

Cheers :)

Don

Thanks, Don. I have to use every advantage I can think of since I don't always have the right tools and I sure don't have near the talent of a lot of you guys!

Chuck
 
Here's a couple of photos of the engine partially assembled. I rounded the vertical edges of the oil pan and it looks better that way! Had to use a file since I couldn't figure out any other way to do it...

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Next I'm laying out the lines and drilling the holes in the head to accept the air supply tubes and the slave valve assemblies.

Chuck
 
Awesome Chuck, I really like the look of it. Still waiting to see how the rotary valve will look like. Please give us details on it when you start?

Don
 
Awesome Chuck, I really like the look of it. Still waiting to see how the rotary valve will look like. Please give us details on it when you start?

Don

Thanks, Don, I hope that part will be coming up soon!

One last picture for the day. I finished soldering the bolt flanges onto the inlet air tubes this evening.

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The flanges are a little bulkier than I'd like, but I'm not inclined to try to slim them down at this point. Next I'll have to assemble the flange nuts and then put the flange on the bottom end of all the tubes. I hate it when I get to this part. One little misstep can flush a lot of work down the drain!

Chuck
 
Looking great Chuck :)
 
Looking great Chuck :)

Thanks. I'll be mightly glad to get past all this fiddly work and get back to parts that are less susceptible to error!

I managed to sneak in a little more shop time this morning. I got the air inlet tubes all flared with the flare nuts in place. It was really pesky getting the length on those tubes correct. There is very little margin for error. I used a piece of 5/8" thick cold rolled steel plus an .008" feeler gauge blade clamped in the vise as a gauge and filed the tubes to length. I would have used 3/32" compression fittings if I'd been able to find any, but didn't have the patience to search the internet for them. I might have gotten by with using a short length of 1/8" tubing as a compression fitting. Need to try that some day, it would be a simple solution.

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Chuck
 
It is really shaping up nicely. Keep it up.

Vince
 
Thanks for the support and the comments. Keeps me plugging away at times I'd rather be doing something else! :)

Here's a video of me using my new Arduino dividing head, built and programmed by yours truly, to cut the small timing gear. Kind of boring for you guys to watch, but I found it very exciting to do! That electronic dividing head makes gear cutting a breeze. I also have a video of me cutting the larger timing gear out of brass, but I haven't loaded it yet.

[ame]http://www.youtube.com/watch?v=A6CrFMwxbxQ[/ame]

Chuck
 
Here's a picture of the gears (so far).
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Chuck
 
awesome Chuck, you mill makes short work of those gears. I like it got to maske me one of those.

Don
 

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