Author Topic: Comber engine question  (Read 4399 times)

Offline GailinNM

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Re: Comber engine question
« Reply #15 on: May 04, 2016, 05:03:01 AM »
I finished up what I had to do early. I attached the DWG and DXF files to this post and the forum software has not complained yet so we try it.
Have fun.
Gail in NM
I would like to be the kind of person my dog thinks I am.

Offline sid pileski

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Re: Comber engine question
« Reply #16 on: May 04, 2016, 02:25:43 PM »
Gail- I brought this into CamBam. It looks like it might work.
I'll give it a try and let you know.

Thanks, Sid

Offline GailinNM

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Re: Comber engine question
« Reply #17 on: May 04, 2016, 08:14:01 PM »
Sid,
Glad to be of assistance.
A couple of notes.  As you probably guessed, the diagonal lines were just to check the center to center distance at a couple of random points. 

In my original instructions I said to spline the polyline curve. I did not do so on the files I sent you as the file size becomes a monster.  This morning I did a quick check to make sure that the error from not doing so was OK.  The error is much less than 0.0001 inch so there is nothing to be gained by splining the curve.

If you haven't already, I suggest that you use ball bearings for the cam follower rollers.  The rollers will be rotating at about 15 times the engine RPM so will eat up lots of power and need lubrication if plain rollers are used. I use ball bearings on almost all rotating parts any more.  AvidRC  has bearings at a good price and provides excellent service in the US. Chinese bearings of course but I have used over 100 of them with no problems.
http://avidrc.com/product/9/standard-bearings/

Gail in NM
I would like to be the kind of person my dog thinks I am.

Offline sid pileski

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Re: Comber engine question
« Reply #18 on: May 05, 2016, 03:51:57 PM »
Gail- Yes, my design is using bearings in all locations, with the exception of the valve body.
I'm almost done with the design at this point.

Yes the file with all of the 720 little segments was too much for CamBam to handle for whatever reason.
I had one of the guys at work proccess it through BobCad. That worked. Took the file to my mill. It ran OK their, but have mot cut
metal yet.


Sid

Offline sid pileski

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Re: Comber engine question
« Reply #19 on: May 05, 2016, 05:15:15 PM »
Here is a PDF of the design.

Hope the attachment works.

Sid