A design for a belt-driven Jacot Tool ...... ?

[VWatchie]

17 minutes ago, mikepilk said:

I'm sure they are wonderful, at about 160 euros, but for the few times I use it, I'll have to stick with my cheapo Indian version (and keep an eye on ebay)

13 minutes ago, nickelsilver said:

Ha, yes, much less painful on Ebay! And secondhand, they are rarely worn or abused, since folks don't use them much, haha.

 

If the wife knew how much money I spent on tools she would probably have a heart attack (and me too if I started to count on it). Fortunately, watch tools are so small and seemingly inconspicuous that she suspects nothing and I can keep being in denial 

Edited July 5 by VWatchie

[LittleWatchShop]

30 minutes ago, nickelsilver said:

Most Jacots I've seen and/or purchased didn't come with a burnisher

May Dad left the Jacot to me and I believe it is complete.  Here are pictures of the burnishing tool.

I have only used the sapphire burnisher when using my lathe.

Edited July 5 by LittleWatchShop

[valleyguy]

I've been looking at pivot file burnishers to use with the jacot tool i've just cleaned up, there are a couple of online write ups about making an homemade pivot burnisher, one using a drill bit the other a tungsten carbide. Links below.

https://joyofprecision.com/post/11833625959/making-a-burnishing-file

https://www.snclocks.com/TechnicalInformation/Tid-Bits/Tid-Bit-11-Making-a-Burnisher/

https://abouttime-clockmaking.com/downloads/Burnishing.pdf

 

I will have a go at making a couple of burnishers at the weekend, one finished with 600 grit the other 400 grit, see if they work or not.

Edited July 5 by valleyguy

[LittleWatchShop]

3 hours ago, VWatchie said:

If the wife knew how much money I spent

I read somewhere or heard someone say: "My greatest fear is that when I die, my wife will sell my tools for what I told her I paid for them."

Edited July 5 by LittleWatchShop

[VWatchie]

43 minutes ago, LittleWatchShop said:

I read somewhere or heard someone say: "My greatest fear is that when I die, my wife will sell my tools for what I told her I paid for them."

I guess that could have been me! 

I guess one easy way to determine if a burnisher is good enough is to have a long good look at the pivot and the pivot shoulder under really strong magnification in a stereo microscope.

[JohnR725]

1 hour ago, LittleWatchShop said:

"My greatest fear is that when I die, my wife will sell my tools for what I told her I paid for them."

that's actually a very common concern with the people at the various chapters of the national Association of watch and clock collectors. Typically it's not with the tools because there aren't that many people repairing their more people collecting. But apparently collectors don't like to tell what they paid for things. On the other hand just think of the opportunities later on for acquiring new stuff so there's always a positive spin on things and the person who's losing their valuable stuff probably won't be here anyway so why should you care.

[oldhippy]

You won't have any fear when you are dead. In fact you won't have anything at all. 

[Nucejoe]

2 hours ago, LittleWatchShop said:

"My greatest fear is that when I die, my wife will sell my tools for what I told her I paid for them."

 You can get even with her in advance, start selling her belongings now. 

 

 

Edited July 5 by Nucejoe

[VWatchie]

10 hours ago, JohnR725 said:

On the other hand just think of the opportunities later on for acquiring new stuff so there's always a positive spin on things and the person who's losing their valuable stuff probably won't be here anyway so why should you care.

So with this rationale, I guess we could say that there's a positive spin on robbery murder as it will enrich the robber and the victim won't care as he's dead.

In principle, I think it is wrong that someone can enrich themselves disproportionately at the expense of someone else.

[JohnR725]

29 minutes ago, VWatchie said:

So with this rationale, I guess we could say that there's a positive spin on robbery murder as it will enrich the robber and the victim won't care as he's dead.

In principle, I think it is wrong that someone can enrich themselves disproportionately at the expense of someone else.

you of a really interesting view of the world can't say I agree with what I see here at all.

[Endeavor]

Let's talk about cricket, here are the latest results;

https://www.icc-cricket.com/live-cricket/mens-results

[VWatchie]

3 hours ago, Endeavor said:

Let's talk about cricket, here are the latest results;

https://www.icc-cricket.com/live-cricket/mens-results

Are you perhaps hinting that we've somewhat strayed from the topic of "A design for a belt-driven Jacot Tool ...... ?"? 

[Malocchio]

20 hours ago, nickelsilver said:

Most Jacots I've seen and/or purchased didn't come with a burnisher, or if they did, it was a little skinny thin one for rounding the ends of pivots using the lanterns. Most don't seem to come with bows either, otherwise I've have a dozen bows!

I have the Bergeon burnisher and so far I've only done some pivot rounding. The problem is there's not a lot of space to operate the rather large burnisher. After all there's just a small part of the pivot showing through the disc and when I rotate the burnisher it tends to hit places it shouldn't. I'd be happy with a smaller and more nimble burnisher. Should I work on my technique or would I profit from a smaller burnisher? Any ideas how to make one?

[LittleWatchShop]

14 minutes ago, Malocchio said:

Any ideas how to make one?

@valleyguyposted links above ^^^^^

[HectorLooi]

1 hour ago, Malocchio said:

After all there's just a small part of the pivot showing through the disc

I think you are using the lantern. For burnishing the pivot, you need to use the appropriate size runner.

[Malocchio]

52 minutes ago, HectorLooi said:

I think you are using the lantern. For burnishing the pivot, you need to use the appropriate size runner.

Yep lantern it is. I didn't remember the word. I'm talking about rounding the balance staff ends. I looked at valleyguy's links, sure I could just make a smaller version. Does anyone have experience on specifically making a rounding tool? Would that be even called a burnisher or just a file?

[praezis]

Burnisher for pivot rounding look very different from normal burnishers. 
You can even use them for burnishing the cylindrical part in a lantern.

Frank

[JohnR725]

41 minutes ago, Malocchio said:

I'm talking about rounding the balance staff ends.

are you trying to get a really nice round surface to reduce friction? Because you're not supposed to have round balance pivots there supposed to be slightly flat.

[Malocchio]

2 hours ago, JohnR725 said:

are you trying to get a really nice round surface to reduce friction? Because you're not supposed to have round balance pivots there supposed to be slightly flat.

Not round but rounded on the edges like they come new. 

[JohnR725]

2 hours ago, Malocchio said:

Not round but rounded on the edges like they come new.

I was really hoping you'd go for round it's really nice when you reduce the friction on the end of the staff.

then I have a picture of the procedure but there's a problem in that that looks like a grinding stone?

4 hours ago, praezis said:

Burnisher for pivot rounding look very different from normal burnishers. 
You can even use them for burnishing the cylindrical part in a lantern.

I don't suppose we can get a picture?

oh and of course the other problem is doesn't look like it's being used on the particular tool of this discussion so it's probably irrelevant but the idea still there

[Endeavor]

Since we are (as usual) off topic;

Does one first do the pivot-end (if required) and then the burnishing of the pivot or first the burnishing of the pivot and then do the tip.

Some folk say that if you burnish the pivot first, you may scratch the surface of the pivot in the lantern?

Edited July 7 by Endeavor

[nickelsilver]

1 hour ago, Endeavor said:

Since we are (as usual) off topic;

Does one first do the pivot-end (if required) and then the burnishing of the pivot or first the burnishing of the pivot and then do the tip.

Some folk say that if you burnish the pivot first, you may scratch the surface of the pivot in the lantern?

You do the end after the diameter. You want to pick a lantern that rests on the conical part of the pivot, both to avoid scratching and so that enough pivot is exposed so you can work on it. The cylindrical part of a typical wristwatch pivot is perhaps 0.3mm long.

 

The burnisher looks like the photo, and resembles the last image in John's post above. Whether one makes a flat pivot, slightly flat pivot, or rounded pivot, is a matter of discussion (isn't everything in this field?). I recall in school our instructor saying that when the Swiss started supplying replacement staffs for American watches, folks had issues with rebanking. The story is the Americans tended to make flatter pivots, the Swiss, rounder. A flat/flatter pivot reduces the horizontal amplitude somewhat, and can aid in equalizing rates between horizontal and vertical.

 

On the left is a Bergeon normal burnisher, the right the pivot rounding burnisher. It's essentially a flat escapement file with the teeth ground off, with straight grained lines just like the normal burnisher. It's really important to finish off by knocking off the burr formed when rounding the pivot; this does take some practice and a bit of a knack to get it to break off cleanly without scratching the cylindrical part. Basically, you come around with the burnisher until it's almost in contact with the cylindrical part. I do the pivot rounding in the lathe, with microscope, so it's clear when it lets go. Again, John's image actually depicts this, but it probably isn't clear the reason why the burnisher is going all the way to the cylinder like that. Also, I don't use a stone at any point in pivot finishing, it's all from the graver (cutting tool) then burnishers. That's how we were taught in school.

 

You can see the rounding burnisher isn't particularly small width-wise, but it has a very low profile, which allows manipulating it around the pivot in the small space around the lantern.

 

Edited July 7 by nickelsilver

[Malocchio]

Thanks nickelsilver that was really helpful. Are fine escapement files fine enough or do I have to polish and refinish the surface?

[praezis]

15 hours ago, JohnR725 said:

then I have a picture of the procedure but there's a problem in that that looks like a grinding stone?

It is. A square Arkansas stone, that shall assure square  ends as a first stage.

Pic (22) shows the last stage with the rounding burnisher. 
Imagine the burnisher level under the pivot: burnishing the cylindrical part (a remark by Alfred Helwig, Glashutte).

Frank

N.B. nice (as always) drawings by late Hans Jendritzki

Edited July 7 by praezis

[nickelsilver]

2 hours ago, Malocchio said:

Thanks nickelsilver that was really helpful. Are fine escapement files fine enough or do I have to polish and refinish the surface?

 A file, even a 10 cut, is far too coarse. It doesn't have to be polished, but all the teeth must be ground off and the lined surface made. A coarse India stone is about right, or a coarse (about 280 grit, 45 micron) diamond hone. It takes a while to get the teeth off, so still best to start with the finest file you can find.