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Pallet Fork Jig for re-jeweling


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Has anyone ever setup a jig for setting the jewels in a particular pallet fork in order to make the job easier?

Finding NOS Citizen 8110A forks is getting near impossible.  I have just purchased the last of Jules Borel stock of 035-39 PALLET FORK AND ARBOR and I have not been able to find any more NOS (or used) forks. I do have a few 035-39’s in various states of disrepair, mainly needing re-jeweled but getting the jewels set right is a pain in the a**.

Just wondering if anyone’s set up a fork jig, locking it in place, with a stop for the jewels so they are the same length and right position every time without the trouble of putting them in and out of the watch to check before heating and resin?  

If you have any tips or tips on a better way of positioning, I would luv some advice .

I have been following this, anything better? FITTING THE PALLET

Thanks, Will

PS I have not found a video or advice from @Mark

 

Pallet Fork Jig-0020.jpg

Pallet Fork Jig-002.jpg

Edited by Wdc
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8 hours ago, rogart63 said:

You have Bergeon 2281 and 2229 . But i think they cost som dollars . There are other tools that are simpler. 

Thanks, rogart63, nice tools and 2281 looks like just what I need, I’ll keep and eye out for a second hand one.

Until I can find the proper tool I am thinking of a jig as follows.

My primary focus is aimed at setting the jewel the right deep in the fork before shellac. Not deep enough, and the escape wheel teeth will not pass the jewel, too deep and it will free-wheel.

As I see it the relative measurement is from pivot to (out-facing) edge of jewel(s). My thought for achieving  this was the following

·         use a plastic base, drill a hole to fit pivot shaft, just over .28mm (firm fit .29-30mm)

·         Using a NOS pallet glue to the base (3) three stops. One for top edge of each jewel, a stop on ether side of fork to lock it into position.

By doing the above I can lock-in the fork, insert each jewel (set at right length). With everything set same as NOS, carefully lift out the fork, moving it to heating plate for shellac.

For the base I will use ether 1/8" white  Acrylic Plexiglass or Canvas Phenolic (which I have an abundance). Care has to be made with the jewel stops making the short, so that when lifting the pallet fork out of the jig it comes out & free, without moving jewel.

Well again I thank all for your input.

Regards, Will

Below is a (very) rough example of what I am thinking.

 

Pallet Fork Jig Layout-001.jpg

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