Author Topic: Carburator barrel ?  (Read 1003 times)

Offline V 45

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Carburator barrel ?
« on: February 10, 2016, 01:52:11 AM »
 I'm making a carburetor for the hoglet and getting stuck on the way to cut the carb barrel. The carb is very similar to George Britnell's design. The part calls for a cut in the barrel for the idle set screw/stop. For those that have made this carb... how did you make that cut? It looks like it goes 16 degrees past a 90 if that makes sense? Here's the print that shows the barrel in question.

Also, being the 1st carburetor I've ever made. How tight does the barrel fit into the carb body? I have made the barrel without the cut in question and has the slightest clearance. How much is too much ? 

 Thanks for the help !!
 


http://www.homemodelenginemachinist.com/attachment.php?attachmentid=38086&d=1342622677
« Last Edit: February 10, 2016, 02:27:21 AM by V 45 »
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Offline gbritnell

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Re: Carburator barrel ?
« Reply #1 on: February 10, 2016, 02:09:33 AM »
To cut that groove set up the barrel in a dividing head or something similar. Make the cut with a small end mill first making the through pass and then rotate the barrel to the proper angle. As far as the fit, make it as close as possible but still allowing a smooth free rotation.
gbritnell
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Offline V 45

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Re: Carburator barrel ?
« Reply #2 on: February 10, 2016, 02:26:12 AM »
Well....that was fast !! Thanks George !! The only thing I could use would be a rotary table vertical with a 3 jaw chuck attached. I wish I had something to hold my 5C collets. With the fit, I had used a new 3/8" end mill to finish the hole after drilling a smaller hole and just lightly used some crocus cloth to take the marks off. I used 3/8" brass rod and just touched that as well with crocus. It seems a nice fit. I couldn't figure out how to make that cut...now I know.  Now to make it work...the vertical learning curve just went up again !!
 While your here...does the main fuel jet (brass part) protrude into the barrel (center/ midway up) or just sort of flush with the cross hole in the barrel?
  One more...the needle I made from drill rod...when assembled and threaded all the way on. the needle doesn't protrude the brass jet. Is that the way it's supposed to be?
  Thanks again
 
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