Author Topic: Compressed Air V8 Engine  (Read 54399 times)

Offline RMO

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Re: Compressed Air V8 Engine
« Reply #45 on: July 29, 2012, 07:02:52 AM »
Chuck,

Thanks for sharing. I am getting more and more motivated watching your work.

Mike O

Offline cfellows

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Re: Compressed Air V8 Engine
« Reply #46 on: July 31, 2012, 03:17:31 AM »
Thanks Dean, Jim, Mike...

I'm getting into what is arguably the most tedious part of the project.  I've more or less settled on the air valve and delivery system.  This part is hard because I want to keep the engine looking as much as possible like an IC engine which means keeping the air plumbing as inconspicuous as possible.

Here's a picture of where I am so far...



First I drilled the 7/32" axial hole along the top of the block.  The brass tube with the air connection on the end will be Loctited into place later.  The rotary valve will be a 3/16" length of drill rod with a 3/32" hole drilled lengthwise most of the way (but not all the way) through from the back.  A flange will be soldered onto the back of the tube.  This tube will then be inserted into the brass tube from the back of the engine.  The flange will fit inside the air connector and will ride on a shoulder inside.  This is the stop that will keep the valve tube from just sliding out the front of the engine when air pressure is applied to the back.  The secondary cam gear will be mounted on the front side of the air tube and turn it at 1/2 the crankshaft speed.

Radial holes will be drilled through the side of the brass tube and the valve rod.  These holes, which can barely be seen just below the ridge of the crankcase will then supply air through 3/32" brass tubes to the top of the cylinders.

The hex pieces are made from 3/16 hex brass.  They will be threaded, cone side up, into the holes along the ridge of the crankcase.  A 1/16 axial hole will be drilled through the center of each one.  The brass tubes will have a flange and threaded caps to hold them onto the brass hex pieces.

OK, so is everyone thoroughly confused now?

Chuck
« Last Edit: August 23, 2013, 09:47:15 AM by arnoldb »
So many projects, so little time...

Online steamer

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Re: Compressed Air V8 Engine
« Reply #47 on: July 31, 2012, 10:14:19 AM »
Looking like a nice build Chuck!   Can't wait to hear her running!

Dave
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Offline dsquire

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Re: Compressed Air V8 Engine
« Reply #48 on: July 31, 2012, 03:40:22 PM »
Chuck

Your moving right along with this build. If your not careful you could end up with an engine.  :ROFL: :ROFL:

Cheers  :cheers:

Don
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Offline cfellows

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Re: Compressed Air V8 Engine
« Reply #49 on: August 01, 2012, 01:19:37 AM »
Thanks, Don, Dave.

I think I've got the details of hooking up the air tubes worked out.  I made a prototype today.  It's fiddly work and the prototype doesn't look very professional, but maybe I can do better on the rest.

I think the pictures will tell the story...





The end that threads into the crankcase is a 5-40.  The other end is an 8-32.  The through hole is 1/16" and the OD of the brass tube is 3/32", ID is 1/16".  I'll take a picture of the fixture I made to flare the end of the brass tube. 

I'll probably be tearing my hair out by the time I get these air tubes all done.  Gonna be a challenge!

Chuck
« Last Edit: August 23, 2013, 09:47:36 AM by arnoldb »
So many projects, so little time...

Offline ironman123

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Re: Compressed Air V8 Engine
« Reply #50 on: August 01, 2012, 04:24:03 AM »
Slow but sure.  Looking good Chuck.

Ray
Ray
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Offline cfellows

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Re: Compressed Air V8 Engine
« Reply #51 on: August 01, 2012, 04:27:56 AM »
Slow but sure.  Looking good Chuck.

Ray

Thanks, Ray. 

This is the fixture I made for flaring the 3/32" tubing.

Two pieces of 1/4" thick aluminum bar stock, several inches long, are clamped together evenly in my drill press vice.  Then, using a center drill, I drill a small countersink at the exact point where the two pieces come together.



Next, I change to a 3/32" drill bit and finish drilling the hole all the way through the two pieces.



Then, I take the two pieces to the belt sander and sand off a small amount of the two joining surfaces.  This slightly reduces the diameter of the hole which makes it clamp the tubing securely.



Next, I clamp the two halves back in my drill press vice with the piece of tubing extended just to the top surface.  Using a center punch and a couple of light hammer blows flares the tubing into the countersink opening.



That's all there is to it!

Chuck

« Last Edit: August 23, 2013, 09:48:07 AM by arnoldb »
So many projects, so little time...

Offline swilliams

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Re: Compressed Air V8 Engine
« Reply #52 on: August 02, 2012, 11:49:36 AM »
That's good info Chuck. Bound to come in handy sooner or later

Steve

chuck foster

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Re: Compressed Air V8 Engine
« Reply #53 on: August 02, 2012, 12:31:56 PM »
looking good chuck, and thanks for showing how to flair tubing as i know that idea will come in handy.

chuck

Offline RMO

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Re: Compressed Air V8 Engine
« Reply #54 on: August 02, 2012, 04:05:20 PM »
Learned something new....again.

Thanks

Mike O :whoohoo:

Offline cfellows

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Re: Compressed Air V8 Engine
« Reply #55 on: August 02, 2012, 08:14:51 PM »
Thanks Mike, Chuck, Steve.  Nice to have you on board!

I thought I'd include a drawing of the plumbing in case anyone is wondering how this thing is going to work.



I ordered some 8-40 taps and dies for the flare connection and won't be doing much else on the engine til I get those.

Chuck
« Last Edit: August 23, 2013, 09:48:28 AM by arnoldb »
So many projects, so little time...

Offline NickG

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Re: Compressed Air V8 Engine
« Reply #56 on: August 02, 2012, 08:41:35 PM »
Fantastic design and execution Chuck  :ThumbsUp:

Offline Dean W

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Re: Compressed Air V8 Engine
« Reply #57 on: August 02, 2012, 09:34:55 PM »
Thanks for the drawing, Chuck.  We get an idea of what we think it will look like, and it's nice to see if we guessed
right.  I like the way you made the flares for the tubing.  That came out just like factory made.  Good work!
Dean
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Offline AussieJimG

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Re: Compressed Air V8 Engine
« Reply #58 on: August 02, 2012, 09:36:10 PM »
I just love that innovative valving arrangement. You certainly come up with some great ideas. Thanks. :whoohoo:

Jim

Offline BillTodd

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Re: Compressed Air V8 Engine
« Reply #59 on: August 03, 2012, 12:38:50 PM »
Very neat, Chuck :)

Is there a reason why you chose bearing balls over say a bearing roller for the valve? (Just thinking a roller  would give a better seal while still being hard and exact diameter)

Bill
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