A little bit of making.

Evening all,
The patient - A French Mantle piece clock, which has a balance not dissimilar in size to a pocket watch.
Unfortunately its been dropped and the top pivot is now in 2 pieces.

https://i.postimg.cc/fTn7FcJY/IMG-5617.jpg

A little bit of disassembly and the fun can begin :)

https://i.postimg.cc/RZv7Cv1F/IMG-5624.jpg

You can see the shorter pivot on the balance spring end.

https://i.postimg.cc/26Lv9yYH/IMG-5625.jpg

So what to do?
Well, break out the lathe and a piece of blued steel and get going...

https://i.postimg.cc/BZDHxjMb/IMG-5631.jpg

Grain of rice for scale.

https://i.postimg.cc/7LfTbh5x/IMG-5651.jpg

Around this point I got hacked off with having to hand sharpen the gravers.
Maintaining the angle and flatness on them is tricky by hand, even with my makeshift jig.
So I took a day out from making the staff to make a grave sharpener (like you do).

https://i.postimg.cc/13Wq9w5C/IMG-5694.jpg

This is 1/8 diameter micrograin carbide. took about 2 minutes to make into an acceptable graver.
https://i.postimg.cc/vTRnJyHG/IMG-5697.jpg

https://i.postimg.cc/W1SMhxS7/IMG-5698.jpg


Back to it - now more like a balance staff shape.
Of course I didn't read the accepted way round (roller table innermost) to make one until after I'd got a good way along.

https://i.postimg.cc/9fMyT1nH/IMG-5701.jpg

Undercutting the rivet took some care, as did turning the top pivot.

https://i.postimg.cc/HLMdS8nv/readytopart-2.jpg

I found a good way to stop the loss of small parts when parting off - a tube filled with grease over the part.

https://i.postimg.cc/yxFRBGkc/IMG-5706.jpg

Having not lost my new staff I riveted it to the balance. I think I should make a smaller hammer...

https://i.postimg.cc/pXJj6gNt/IMG-5710.jpg

And now it needs a little touch up of the pivot sizes on the Jacot tool:

https://i.postimg.cc/jdbNvRFX/IMG-5711.jpg

Once I figure out how to use a Jacot so the balance and staff don't jump out all the time Ill post an update.
If anyone has any tips they would be gratefully received.

Dave

Very interesting. Great to see traditional skills in use and enjoyed. I repivot platform escapement staffs when I'm bored !
Have you tried finishing the pivots in the lathe chuck with 3M papers stuck to lolly pop sticks ? 3M papers come in 6 grades from coarse (blue), which is Arkansas stone coarse, to mirror finish (white).

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Didn't understand a thing in that but really interesting, thanks

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Originally Posted by subseastu

Didn't understand a thing in that but really interesting, thanks

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I guess all watchymakery words are googleable ?

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No, I’ve not tried in the lathe. I have some boxwood and diamond paste which would work I think.
The bottom pivot fits the jewel, but might be a bit tight. The top one is ~0.01mm to big. (The one I couldn’t measure until parting off)
I could use a wax chuck I guess to support the staff - the roller seat is tapered and would walk out of a normal collet I think.
But then I do have a Jacot tool with a bow and burnisher that I should probably learn to use.
The problem is that the staff is not very secure in the female centre and so it jumps out really easily. I wondered if there is some “secret” like a small blob of grease on the centre that I am missing?

Dave

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Originally Posted by Dave S

No, I’ve not tried in the lathe. I have some boxwood and diamond paste which would work I think.
The bottom pivot fits the jewel, but might be a bit tight. The top one is ~0.01mm to big. (The one I couldn’t measure until parting off)
I could use a wax chuck I guess to support the staff - the roller seat is tapered and would walk out of a normal collet I think.
But then I do have a Jacot tool with a bow and burnisher that I should probably learn to use.
The problem is that the staff is not very secure in the female centre and so it jumps out really easily. I wondered if there is some “secret” like a small blob of grease on the centre that I am missing?

Dave

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The Jacot tool is fiddly and takes some practice to perfect it's use. Slight downward pressure on the bow and a small drop of oil on the pivot runner whilst keeping the burnisher in constant contact with the pivot should help to stop it jumping out of the runner bed. Depending on how well finished the pivot is initially, will determine the time needed to burnish it smoothly and to exact size. The advantage of the Jacot is that the pivot will have perfectly parallel sides. Runners need to be kept very clean as you can imagine to avoid scratching the pivot sides. Finishing the end of the pivot to a smooth round is done by passing it through the appropriate hole on the ends runner.
It's a lot quicker to finish the pivot in the lathe and with 3M papers but the Jacot art is then lost. The lathe doesn't do as good a job.
You are right that the coned roller end can slip out of the chuck, though a very slow speed reduces that risk. Substituting a wax chuck would certainly help.
*I have seen a thin open elastic band, attached at one end under the Jacot tool, used to turn the ferrule, instead of a bow.
Best wishes for a successful outcome.

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I'm no expert in Jacot lathes but I do use mine occasionally!

What I can't see on yours is the forks on the drum that turn the wheel when you move the bow? You can see them on mine below.

https://thewatchbloke.files.wordpres...9/p1350454.jpg

https://thewatchbloke.files.wordpres...9/p1350455.jpg

I find it easier with the forks positioned nearer to the centre of the wheel but it's still a very tricky process to learn.

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Originally Posted by Thewatchbloke

I'm no expert in Jacot lathes but I do use mine occasionally!

What I can't see on yours is the forks on the drum that turn the wheel when you move the bow? You can see them on mine below.

https://thewatchbloke.files.wordpres...9/p1350454.jpg

https://thewatchbloke.files.wordpres...9/p1350455.jpg

I find it easier with the forks positioned nearer to the centre of the wheel but it's still a very tricky process to learn.

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Yes. I noticed that too. Without the carrier on the ferrule the wheel would not turn. I presume it was left out for photographic clarity.

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Wonderful.

Thanks for sharing, the only way to go when you can't source spare parts.

That is superb

Just WOW


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Originally Posted by barbosas

Wonderful.

Thanks for sharing, the only way to go when you can't source spare parts.

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I do have a huge selection of watch balance staffs, referenced by their Ronda number or actual dimensions. I am happy to supply if anyone needs a staff or two.

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Aha!
My driving dog is just a single point piece of wire. You can see it in this short clip:

https://twitter.com/solutionsbydave/...511477760?s=21

I presume that the fork slightly grips the arm of the balance? That would stop it popping out of the female centre every time the direction changes.
On a lathe of course the direction doesn’t change, so a single drive dog is normal.
I wonder if the previous owner had this Jacot tool hooked up to a lathe motor so it always turned in a single direction.

Can you post a close up pic of the fork - I think I’ll be making one shortly...

Dave

Impressive seriously, the last lathe work I did was a 30” dia x 48”drum from a conveyor belt that had worn flat -need a slight belly on them- definitely not the intricate work like yours, if I hat on I’d tip it to you Sir.

The fork on mine doesn't actually grip the wheel but I do keep the burnisher in contact with the pivot whilst drawing the bow to prevent it lifting out of the lantern.

In Donald de Carle's book it shows a diagram of a Jacot tool with (like yours) just one bent piece of wire to drive the wheel so it must have been common practice to use that method rather than a fork back in the day.

I’ll have another try tonight with the burnisher then, before making a fork. I thought the jerk in direction change was the main culprit, but maybe it’s just my clumsiness .

Dave

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Originally Posted by Dave S

I’ll have another try tonight with the burnisher then, before making a fork. I thought the jerk in direction change was the main culprit, but maybe it’s just my clumsiness .

Dave

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You might find this video helpful:

https://youtu.be/f-8Vd2m-WBs

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Thank you. I think the fork shown would stop the problem I have where the staff jumps out of the female centre.
Think I’ll make a fork and then have another practice

Dave

Quote:

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Originally Posted by Dave S

Thank you. I think the fork shown would stop the problem I have where the staff jumps out of the female centre.
Think I’ll make a fork and then have another practice

Dave

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The guy on YouTube seems like a real enthusiast. He keeps his pivot file over the staff all the time he's turning the ferrule. That way it can't lift out of the slot.
Very best wishes with your endeavour.
The Finisher, in Victorian times, was one of the most skilled of all the watch jobbers. He would have specialised in that aspect of watchmaking alone. On really high quality English levers you will see a step cut just above the pivots of the staff for oil retention. Such incredible skills involved in making that tiny cut.

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It's all very well messing about with watches Dave, but how's the Porsche coming along? ;-)

Love lathe work there.

Well done that man.

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Originally Posted by magirus

It's all very well messing about with watches Dave, but how's the Porsche coming along? ;-)

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Not very fast..
The engine is ready to go back in, but foolishly I though whilst it’s out I’ll just...
Which has resulted in the need to remove some tin worm. That would have needed doing anyway, but the whole job seems Sisyphean and I have a hard time summing up enthusiasm for it. The house move didn’t help as I lost what momentum I had to get it done.
So I thought I might knock out a bit of horological stuff in the hope of building my motivation back up.

Dave

Quote:

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Originally Posted by magirus

It's all very well messing about with watches Dave, but how's the Porsche coming along? ;-)

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Quote:

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Originally Posted by Dave S

Not very fast..
The engine is ready to go back in, but foolishly I though whilst it’s out I’ll just...
Which has resulted in the need to remove some tin worm. That would have needed doing anyway, but the whole job seems Sisyphean and I have a hard time summing up enthusiasm for it. The house move didn’t help as I lost what momentum I had to get it done.
So I thought I might knock out a bit of horological stuff in the hope of building my motivation back up.

Dave

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I hope you get the motivation back Dave! Meanwhile, great work on the watch front! :pig:

So it turns out its just a matter of excellent fine motor skills and coordination, no fork needed, the rather sad looking piece of bent wire works just fine ;)
I was slightly surprised, but you can feel when the burnisher is working correctly. I think I need to invest in a single Jacot which has all the parts.
I currently have the one in the videos, which has only 1 set of beds but seems to be better made, and another, which has 1 set of the holes and a couple of beds, but isn't as well made.
Of course the 2 have different sized bars so I cant use the holes in the nicer Jacot...

I can't figure out how I get a video into a post, but here is a link to me managing to not ping the balance off all the time https://imgur.com/l5oLGzE

This evening I've managed to get a pair of burnished, correctly sized pivots on my newly turned staff. First a photo for context:

https://i.postimg.cc/J0jpvqzP/IMG-E5722.jpg

The 'thread' is one of my hairs, which I pulled out specially for scale.
You can see it nice and clearly in the next photo, taken through my toolmakers microscope (40x mag):

https://i.postimg.cc/rmBhfbMD/IMG-5721.jpg

I'm not sure the pivots are 'perfect', but they are at least the correct size, parallel and in one piece <Hurrah for Small Victories>

An finally a link to a short clip of the balance 'installed' in the carrier which fits in place of where a pendulum would go if this movement was in a pendulum regulated clock.
https://imgur.com/q8PgkY2

Next job is to fit the roller table and balance spring, then reassemble the escapement and send it off to get fitted to the clock.

Thanks for the help

Dave

Excellent! I've replaced some, but never made one.

Best wishes,
Bob

Congratulations ! That looks pretty damn good to me ! I will be very surprised if you don't get a superb amplitude when it's all reassembled.

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My work is in precision turning so this kind of stuff is right up my street....In fact our Swiss type CNC's were originally developed by Citizen to manufacture components for their watches. However, there's nothing like some back to basics highly skilled lathe work.

Top stuff.

Nice job Dave, I'm sure all the fork achieves is less backlash between direction changes with the bow. As you've proved it was just the lack of the actual burnisher that was causing the issue.

Now poise that balance! :worked_till_5am:

Finished. Wasn’t far out of poise, which I think is to be expected.
Apologies for the twitter link, it’s to a couple of second video of a ticking balance.
https://twitter.com/solutionsbydave/...197813760?s=21
I don’t have the rest of the clock, but this module is ready to go back to it and get fitted.

Should probably get on with learning Dial Enamelling now...
https://i.postimg.cc/8zYr5nyw/F23218...75-A1-EE33.jpg

Dave

Well done that man ! Congratulations on keeping these arts alive.
I shall be visiting an enamel dial maker in Switzerland this October and hope to add a couple of chapters on how to make them in my book.
https://uploads.tapatalk-cdn.com/201...fa7e134604.jpg

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Very small update on this.
The balance module is now installed back in the clock and ticking nicely.

https://i.postimg.cc/CBgHNYDr/4-A891...-AA07-DF74.jpg

The clock has three trains, one of timekeeping and two for the chimes. It now needs a service and re-casing but that’s not my job :)

https://i.postimg.cc/14yrVmyf/2-BF56...87-D9-D832.jpg

https://i.postimg.cc/Z93xp09y/DE5-BE...0488-E5-DB.jpg

There’s a short video on my Twitter:

https://twitter.com/solutionsbydave/...012129281?s=21

Dave

Nice job Dave. It's great to get something working again.

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