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Jim Parker Toronto 04-14-2012 06:49 PM

Distributor Cam Screw
 

Does anyone know what the screw size is that holds the cam on the shaft. I've checked everywhere I can and can't seem to locate the proper size. Thanks in advance, Jim

dave in australia 04-14-2012 07:18 PM

Re: Distributor Cam Screw
 

This was discussed awhile ago. It is an odd size unique to the shaft and cam. I can't remember the size but I seem to recall the pitch as 30TPI, also no metric equivelant.

Jim Parker Toronto 04-14-2012 07:29 PM

Re: Distributor Cam Screw
 

Quote:

Originally Posted by fordgarage (Post 406491)
Original or reproductions? Most of the repros will not fit an original shaft, only a repro shaft. :mad:

I guess that we're looking for the repro size.

RHD 04-14-2012 09:03 PM

Re: Distributor Cam Screw
 

I have just checked. 30 tpi, but it measures 5/16". I have tried all combinations of new screws into old shafts etc and no matter what combination I have they all fit 100% as I suspected.
Another line of thought. Have you ever tried fitting a 30 repro dash lamp cap onto an original base. Just won't go by a minute amount. You would think, whoever made the repro caps would at lease get their measurements right. No way will I ever be buying any more repro caps, that's for sure.

Preacher 04-14-2012 10:04 PM

Re: Distributor Cam Screw
 

the original thread is .325 -30

Jim Parker Toronto 04-15-2012 10:08 AM

Re: Distributor Cam Screw
 

Quote:

Originally Posted by Preacher (Post 406642)
the original thread is .325 -30

Thanks, boy that's really an odd size! I wonder why Henry did it like that? It sure makes it hard to make a distributor puller. Jim

Bubby Sharp in KY 04-15-2012 04:19 PM

Re: Distributor Cam Screw
 

Jim, See Snyder's page 146 in new catalog for puller stud part # A-12130-DPS $ 13.25 . I made my own , but my buddy Joe used the bought one. If you know someone with a lathe they can make you one.

leo 04-16-2012 08:57 AM

Re: Distributor Cam Screw
 

Hey fordgarage, I found your comment most interesting. Are you saying that some reproduction shafts and cam screws are not .325-30? I find that hard to understand because machines which cut threads are very exact. Why would any manufacturer go through the process of making a thread size any different than what it should be?

Big John 04-16-2012 10:07 AM

Re: Distributor Cam Screw
 

welcome to repro parts world...alot of which is junk...

dave in australia 04-16-2012 07:31 PM

Re: Distributor Cam Screw
 

Quote:

Originally Posted by leo (Post 407404)
Hey fordgarage, I found your comment most interesting. Are you saying that some reproduction shafts and cam screws are not .325-30? I find that hard to understand because machines which cut threads are very exact. Why would any manufacturer go through the process of making a thread size any different than what it should be?

Probably because it is easier to use commercially available cutting tools, which don't list .325-30 as a size. Another possibilty is that when they sized the part to copy, someone had allready hacked it up with the wrong size cutting gear. I have several shafts ruined by a previous owner/mechanic cleaning up the thread with them using a 5/16 32 tpi cutting tool. A lot of replica manufacturers copy a worn out part and the person getting the part replicated does not explain that it is worn and where it needs to be changed to bring it back to original size, so they end up with a new,worn out part.

Bill Stipe 04-16-2012 09:01 PM

Re: Distributor Cam Screw
 

I Mfg the dist pullers and stud if your looking for just the stud call SueAnn she can help. If your looking for a tap you would have to have it custom make.

Bill Stipe

Jim Parker Toronto 04-16-2012 11:22 PM

Re: Distributor Cam Screw
 

Thanks Bill, just got my order from you last week. Could have shipped them both in the same package! Someone suggested that if I knew someone with a lathe, I could have a screw cut. Two weeks ago got my new to me (1965) Standard Modern lathe moved to its spot in the shop. I advertised the old one (1941 Revitt) and sold it in 5 hours. I cannot cut a 30 TPI on the new lathe, so I checked the old one. Sure enough, as it was going out the door, I checked the data plate, and it would do it! Who says newer is better? Other than that, I do like the newer lathe better....

JoeWay 04-17-2012 09:38 AM

Re: Distributor Cam Screw
 

"Commercially available cutting tools" for a job like this would likely be a Geometric-style die head, Swiss screw machine, or CNC lathe, all of which can easily be set up to cut an oversized thread of odd pitch (with 0.325" being an oversize of 5/16").

The major diameter of properly cut threads is usually about 0.005" under nominal, as the crest is truncated to avoid a sharp edge. 0.320" sounds just right to me for a nominal 0.325 thread.

Joe

V4F 04-17-2012 10:43 AM

Re: Distributor Cam Screw
 

get one from a store . get the correct one !! any model a place will have them .


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