Jump to content

Jacot tool and pivot file burnisher question


Recommended Posts

1 hour ago, Tmuir said:

The other gauge is part of the jacot tool, its for measuring the size of the pivot, I agree that the rubber bands are not for the jaccot tool

My eyesight lets me down again.:biggrin:My brain lets me down too.

Edited by oldhippy
Link to comment
Share on other sites

  • 9 months later...

I've got a Unitas 235 that has a cracked jewel that also damaged the pivot on the third wheel.

Cousins still has replacement third wheels for this movement, so safe with the knowledge I can order a repalcement wheel I decided it was time for me to try and polish the picot with my Jacot tool.

I've polished pivots on clocks no problem, but this is the first time I have tried on a watch pivot.

I'm amazed at just how much harder it is to polish the pivot on a watch.

I've butchered the pivot enough that I will be ordering the replacement wheel, but will continue to polish this pivot now just for practice.

The few things I have learnt from my attempts so far are.

  • Check the pivot dimension closely and select the correct diameter slot on the Jacot tool, don't just go 'close enough'
  • Ensure you have set up the tool so there is no slop in the way it is holding the wheel, else the wheel will tilt by a degree or 2 as you move the bow and burnisher backwards and forwards making it easier to end up with a tapered pivot
  • Take care on how you hold your burnisher to make sure its parallel to the pivot.
  • Get yourself a few wheels to practice polishing pivots from junk movements before touching an important wheel
  • Give yourself a break and go read WRT if you feel your pulse rising. :D

I may of done a crap job on polishing this pivot, but atleast I can say that I've started to learn how to use my Jacot tool now.............

  • Thanks 1
Link to comment
Share on other sites

Working with such a tool for the first time, you are going to make mistakes. Just working with a bow is an art in its own right. Knowing where you went wrong and correcting is part of the fun. You will get there in the end so just keep it up.

  • Like 1
Link to comment
Share on other sites

I went back last night and practiced some more. I got better results, but still not good enough.

I'm leaving it like that until I receive the replacement wheel and confirm it fits, because if it doesn't I will be taking it in to my night class and asking for help before I ruin it.

But once I'm sure the replacement wheel fits I will continue to practice on this one until I get it correct.

I also just received today a trashed English leaver fusee movemt that I only paid $20 for. Its too far broken to ever be made a working timepiece again, but will  prove me plenty of learning potential on a type of watch I've not touched before.

Far better to learn on a $20 wreck of a movement that a several hundred dollar good example.

 

Link to comment
Share on other sites

  • 2 weeks later...
  • 2 weeks later...

Hi folks. I just got a Jacot tool from eBay. I'm working through Practical Watch Adjusting by Donald de Carle which has been a brilliant guide. Just a couple of things I'm not sure on.

First, can anyone explain the scale on the pivot measuring tool? Why are the numbers on the left and right side different? I don't see how they relate.

Also, can anyone explain how to secure the work piece to the tool? The ones I've seen on YouTube have two "snake teeth" that clasp the wheel but this only has one. I can't see how it can hold anything securely.

Thanks all.

IMG_1033.jpg

IMG_1032.jpg

IMG_1034.jpg

  • Like 1
Link to comment
Share on other sites

I have never used that type of gauge for pivots, so I don’t know about the measurements. I know you slide the pivot along on the inside until it stops and you read off the measurement.

 

Here is a good video about how to set up a Jacot tool and use it. Working with such a tool takes a lot of practice. Do not start on something you wish to keep, wait until you have the skill.

 https://www.youtube.com/watch?v=f-8Vd2m-WBs

  • Thanks 1
Link to comment
Share on other sites

As you say, there are two sets of numbers on the gauge. 

I'm sure the left hand set of numbers is the diameter of the pivot in Dousiemes, and the right hand set is the appropriate Jacot drum notch that you should use when working with that pivot.  To check this, measure the gap of the gauge at the relavent numbers and see if it corresponds with the sizes I have given.

Here is a conversion of Dousiems to Millimetres.

1 = 0.19

2 = 0.38

3 = 0.56

4 = 0.75

5 = 0.94

6 = 1.13

7 = 1.32

8 = 1.50

9 = 1.69

  • Thanks 1
Link to comment
Share on other sites

Ah. Actually the scale on the left is metric. But I think you're correct about the scale on the right showing which drum notch to use. Mystery solved. Now if I could just attache a balance wheel to the thing. I still can figure out how the "snake tooth" secures it. Thanks Old Hippy for the YouTube link. I had actually watched that one and it's super helpful. Although he doesn't demonstrate on a balance wheel which I understand should have rounded pivot ends. That seems to be a real skill which is going to require a lot of practice.

Link to comment
Share on other sites

The shaft is located between the hollow centre of the driving wheel and the shoulder of the pivot at the jacot end.  The driving dog sits between the the spokes of the wheel to impart the driving force.  Nothing is clamped in place.

  • Thanks 1
Link to comment
Share on other sites

The little slotted gages are kind if sketchy, one of my teachers called them "pivot breaking tool". But for small diameters, say under .13mm or so, a micrometer poses a real threat of making tiny flats on the pivot even with a very light touch. Best is jeweled hole gages, available in .01mm, .005mm, and .0025mm increments. Without those you can get close using a micrometer and then use the actual jewel as a gage, look for about 5° of "tilt" for the correct freedom.

The drive finger is often a pair but a single one works fine.

  • Like 1
  • Thanks 1
Link to comment
Share on other sites

The little slotted gages are kind if sketchy, one of my teachers called them "pivot breaking tool". But for small diameters, say under .13mm or so, a micrometer poses a real threat of making tiny flats on the pivot even with a very light touch. Best is jeweled hole gages, available in .01mm, .005mm, and .0025mm increments. Without those you can get close using a micrometer and then use the actual jewel as a gage, look for about 5° of "tilt" for the correct freedom.

The drive finger is often a pair but a single one works fine.

Need to buy a jewel gauge ruler and a set of pin gauges.c09c8b255244f0ef7d63e38d2c4abf84.png574eae8cbc88d997ecdbe8e68c71a102.png


Sent from my iPhone using Tapatalk Pro
Link to comment
Share on other sites

  • jdm featured this topic
  • jdm pinned this topic
  • Mark unpinned this topic
  • Mark pinned and unpinned this topic

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Restore formatting

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

 Share




  • Recently Browsing

    • No registered users viewing this page.
  • Topics

  • Posts

    • Hey everyone I enjoy tinkering and used to get my fix by making knives, but with a baby (now toddler) that hobby has been put on pause.  My co-workers dad used to be a watchmaker but had to stop due to arthritis. I was lucky enough for him to give me some basic supplies to get started along with some busted movements and books. After destroying one movement I signed up for Mark's online course and have made my way through half of it while working on a couple of my own movements. Eventually I'd like to get to the point where I can buy vintage pieces and restore a handful a year. There is surprisingly little information on watchmaking and this forum has already been a great help. Cheers! Adam  
    • Any chance you can take some pictures and give a quick review of the tool? I suspect many of us will be quite interested in this tool.   I agree that some of the Swiss-branded tools are at least made in part in China, but touched-up/finished marginally in Switzerland. On the other hand, some of the Chinese tools are really a direct clone of the tool, which wouldn’t be so vexing if they actually worked as advertised: I bought some pallet forks for 2824-2 from china which were advertised to be compatible with ETA 2824-2 but couldn’t fit in the jewels. I have had better experience with Chinese tools that have their their own branding (such as Weishi), but even then, there are sometimes multiple listings on AliExpress of seemingly identical items with different Chinese brands. I would think that if one was a Chinese-speaking watch enthusiast in China, it would be easier to locate reliable Chinese tool manufacturers (as @HectorLooi previously mentioned) but for us, we have to rely on actual reviews from people who own the item!
    • Wow a thousand pound watch and the stem removal is booby traped by poor design 😎
    • I have just taken delivery of one of these myself.  After the nightmare I had with a Tag Heuer where the seconds hand popped off its tube when I used hand leavers like I always did with all the other watches I have stripped down, one set of Tag hands cost me £120, so the price paid for the hand lift tool £145 is not so bad if it saves me from that nightmare situation again. They are well made and a quality product, just got to wait for the next Tag to land on my desk to try it out in anger. Also remember not all these Chinese tools are clones or copies, some of them are the same tools some of the Swiss makers claim to make, they have their tools made in China and just package them in made in Switzerland boxes. I have some that are so identical the parts are fully interchangable with the Swiss version and all the machining marks are identical, showing they are off the same production line, and just sent to a different logo printer. The Swiss watch industry is a very shady industry, from watch makers only being bracelet makers who use a generic movement from a movement maker to the likes of Rolex who although they are a multi million company don't pay any tax because they are set up as a charitable organisation but only fund themselves, to their tool makers who have their tools made in China but claim they are made in Switzerland and charge over inflated prices for the same tool that can sometimes be bought direct from China at a fraction of the price the Swiss charge.
    • I don’t normally post about Chinese tools, because I am apprehensive about supporting direct copies/clones of existing tools. However, I recently came across this hand remover press on AliExpress, which looks quite distinct from the existing Horotec one. In fact, it’s design looks quite good, with a movable rack supported head (with Vernier scale) to allow you to adjust the height of the hand remover on the go. Any of you guys interested? The price is also much less than the Horotec one. https://www.aliexpress.com/item/1005004261155255.html
×
×
  • Create New...