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Unusual Jacot Pivot Tool - how it works?


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I recently bought a Jacot Pivot Lathe at a very reasonable price. It is in good condition and seems to be complete. However the design seems to be unusual in that it does not have second hole in one of the arms. I have seen pictures of this particular design and wonder if it was the earlier version of the Jacot lathe? As a result of this odd design I have no idea how to set it up or even how it works compared to the regular Jacot Pivot Lathe. Otherwise the tool looks complete. I would appreciate any advice in this regard. Thanks very muchIMG_7226.thumb.jpeg.39b1980050fc0e28de9f47c87516e1f6.jpeg

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That's a very old example. Newer ones would have the second hole you mention, meant to control where the pulley sits on the simple runner. With these old ones, a pulley was fixed directly to the work, and the bow would run that. In the pic you can see some drive dogs on the left, for larger work turning between centers, the little box with the "fish" that clamp onto pieces also for turning between centers, or to be driven by the finger on the pulley of most Jacot tools, and above that a couple of little pulleys (they get even smaller) for clamping directly on the work.

 

I think you would be best to set this tool aside as a decoration, and find a more modern tool for actual work. If you hunt a bit you can find a modern Steiner for a good price (also called Hahn due to the trademark) like the pic, they are honestly the best. The pic is of two sets stacked on top of each other, one the basic set, the lower one with extra runners.

 

You'll still need to track down a set of the split drivers like in the little box. Still available from Bergeon and Horia at new prices, but can be found used.

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2 hours ago, DrJ said:

I recently bought a Jacot Pivot Lathe at a very reasonable price. It is in good condition and seems to be complete. However the design seems to be unusual in that it does not have second hole in one of the arms. I have seen pictures of this particular design and wonder if it was the earlier version of the Jacot lathe? As a result of this odd design I have no idea how to set it up or even how it works compared to the regular Jacot Pivot Lathe. Otherwise the tool looks complete. I would appreciate any advice in this regard. Thanks very muchIMG_7226.thumb.jpeg.39b1980050fc0e28de9f47c87516e1f6.jpeg

IMG_7223.jpeg

IMG_7224.jpeg

Hi Dj. I think the small one is a re pivot tool with parts missing. I've been looking at these for ages and wondered about the second hole. I saw an example that had the accessory with it

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Thanks very much for the responses. It is otherwise a beautiful antique tool to admire and with time will add a newer Jacot lathe.  Given the older design how old do you think this instrument would be?  Thanks

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