Pivoting Attachment for Watchmakers Lathe

[arutha]

I needed a pivoting attachment yesterday for a re-pivoting job. I have in the past watched them on e-bay, they quite often come with a jacot drum and look like a round disc with holes increasing in size drilled around the outside and make in the region of $180 – $200. I couldnt afford that so I had a go at making my own. It was a little rushed and looks a bit crude but it does the job perfectly, you can even make two or three and have every single size hole you would ever need.
This is designed to fit in the t-rest holder hole which on my Wolf Jahn lathe is 6mm in diameter. This will work for any T-rest holder as long as it takes interchangeable fittings like a roller/file rest etc.

I just cut a piece of 6mm silver steel rod to size and then cut a slot in the top (like a deep screw slot) to fit the “flag”. The “flag” is the piece that has your different hole sizes drilled into it and is also made of steel. Once the slot was cut I then drilled through the rod, from one side to the other so with the flag fitted in the grove I could put a rivet all the way through and then silver solder it in place. For riveting I used a 3mm diammeter piece of blued pivot steel first softened by heating to cherry red and then slowly moved away from the heat source so it didnt cool too quickly. This was then cut to size and hammered in to form the rivet. It is then just a matter of putting some solder around the joins and then drilling whatever size holes you need in the “flag”. As the T-rest is adjustable up and down and across the lathe bed it allows you to drill a few useable holes in your flag but obviously with each lathe being different please check the amount of adjustment you have with your t-rest holder so as to get an idea of how much “flag” area is useable. Like I said it doesnt take long to knock one up so make two or even three and just drill the guide holes in as you need them.
It worked a treat and saved me a small fortune to spend on other tools
I have added a rough drawing, I hope you get the idea but if not please ask.
Paul.

[arutha]

Bob has suggested that the “flag” be hardened and to also make sure the insides of the holes are smooth when going for smaller sizes holes. This will work fine on clock pivots but for watch pivots it might not be accurate enough.

[bobpat]

I have seen so many ways to polish pivots.. What everyones opinion on the best way to do this, ever seen this way?
Carbide-impregnated-polishing-wheels-for-Clock-Repair-Pivot-Polishing.. Saw this on u-tube. some claim it works some claim its not good, . Just picked up a sherline and still learning how to use it.. Lots to learn. Been working on clocks for maybe 10 years, but never lathe work, I do a lot on a woodworkers lathe, but never metal.So you may see a lot of me on here . It’s an awesome site. And, I never worked on a watch, picked up my first pocket watch on the Bay a cheap one, doesn’t work but I think it just needs to be cleaned, I think I am going to like the watches.one more, whats the best material for pivots?. I been practicing on making them, I have harden steel rods that I’ve been turning but the cutter seems too low and not cutting too good, DULL?. Been practicing on brass and it came out great but the steel rods are not,, Sorry for the long post.I quess I was rambling on..

[arutha]

You are always better off posting questions on the general discussion forum as I think a few of the forum users forget about this section.
To answer your question the 3 main ways of polishing pivots is
1.By hand on a block of hardwood using a pin vice – This is the cheapest way but does take a bit of practice, to burnish well you do have to use a fair amount of pressure with the burnisher and if you slip while polishing a delicate pivot you can bend or break them.
2.In the lathe – You can get pivot polishing attachments for lathes (Bob shows you how to make some in his videos) which are jacot drums but they are quite expensive to buy.
3.Pivot polishing machine – These come up on rare occasions on eBay but you have to have plenty of spare money to even think about one of these.
“Carbide-impregnated-polishing-wheels-for-Clock-Repair-Pivot-Polishing” These may polish pivots but I cant see how they would burnish them. Burnishing work hardens the surface of the pivot helping it to withstand wear and last longer, polishing the pivot will make it look nice but wont harden the surface at all and using one of these wheel will only polish a pivot.

The best material for pivots is hardened or “blued” pivot steel, brass certainly wouldn’t be hard enough and wouldn’t last very long. What type of hardened steel are you trying to cut? If you cutter is too low it will just be burnishing the steel and if your cutter is dull it definitely wont cut it.
Paul.

[daryn]

When cutting hardened ( and slightly tempered!) steel most people starting out seem to run the lathe far to quickly, this effectively burnishes the cutting edge of your graver or tool bit , keep trying!

[bernie weishapl]

Paul I need to make a flag for my taig so I can do pivots. I have a idea and will see if I can post some pictures if it works.

[gerene]

Bernie, I am verry interested in your flag for a Taig. Please keep us informed.

Jan

[bernie weishapl]

I will Jan. I hope it works.

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