Jump to content

Jacot tool and pivot file burnisher question


Recommended Posts

Nicely done! Did motorized my pivot drilling/polishing tool after messing a bit with a bow. The bow was grabbing the piece to hard and with the electric motor i can set the pulley so soft, that if the drill is accidentally grabbing in the staff thet the pulley will slip avoiding the drill to break. Not to mention that i can use my other hand to support the file.

I see You have a nice speed-regulator. I am using a cheap PWM regulator. You should spin much faster or you will grow beard :) Does your motor have a transmission gear train? A simple DC motor would be better. 

There is also a great science behind polishing. Like how much and fast You should move the burnisher back and forth compared to the turning speed to avoid flat pinion mantle. 

Link to comment
Share on other sites

8 hours ago, szbalogh said:

Nicely done! Did motorized my pivot drilling/polishing tool after messing a bit with a bow. The bow was grabbing the piece to hard and with the electric motor i can set the pulley so soft, that if the drill is accidentally grabbing in the staff thet the pulley will slip avoiding the drill to break. Not to mention that i can use my other hand to support the file.

I see You have a nice speed-regulator. I am using a cheap PWM regulator. You should spin much faster or you will grow beard :) Does your motor have a transmission gear train? A simple DC motor would be better. 

There is also a great science behind polishing. Like how much and fast You should move the burnisher back and forth compared to the turning speed to avoid flat pinion mantle. 

Most of the cheaper DC motors that I looked at were way too fast for me. This one is geared and I can kick it up by going to 12 volts DC which better approximates my best manual speed. Don't get me wrong... there's nothing wrong with going faster. I'm just not very comfortable with it.

Thanks!

Link to comment
Share on other sites

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

I got myself a jacot tool in poor condition at a high price...

I wanted it for pivot polishing, but then I read on a blog that it is used mainly for burnish or reducing a pivot diameter (only as a last resort as it can do more harm then good) 

any advice or pet on the back?

Edited by matabog
Link to comment
Share on other sites

  • 1 month later...

if you're not making your's staffs at a lathe, or changing cracked jewels you might use it as a paper weight, like I do...

pardon the dark humor...

I suppose you want your balance staffs nice and shiny, like I did - the problem is you'll thin them down - you'll gain side shake and you'll need to change the jewels...

I'm thinking of using polishing paste on 8mm wood rod (instead of the Jacot's steel parts), but didn't get to do that yet.

 

B

 

Link to comment
Share on other sites

2 hours ago, matabog said:

congrats, then! You'll use it for what it was meant :)

You'll need a fine Mississippi stone to tackle the pivot from the top.

Mississippi stone is a new one on me.

I know about Water of Ayr stones, Arkansas stones, Tam O Shan stones, plus the many synthetic stones, but have not heard of a Mississippi stone before, is that just like a Arkansas stone?

Link to comment
Share on other sites

As i understand a Jackot tool is used with different "files" for the different needs.

For burnishing one just using a piece of flat steel with oil to avoid reducing the diameter but make the staff shiny. This method is also excellent to remove hard gum from the pivots.

To reduce the diameter one should not use grinding paste since that will also alter the tool notches. UI would use only abrasive stone or steel file. For example Degussit midget files.

 

Link to comment
Share on other sites

stone, files, burnishing tools are all used with a Jacot tool, the Jacot tool is covered in the Lathe section in the DeCarle book (Chap. 17)

I use mine all the time, but I work mainly on late 1800's to early 1900's watches, the pinions need to be polished, I believe Stephan Pahlow has a video out where he is also using a Jacot tool,

Link to comment
Share on other sites

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.




  • Recently Browsing

    • No registered users viewing this page.
  • Topics

  • Posts

    • that band is old as stated, there is a kit that pops up from time to time on selling sites for the repair of these type bands, some of this type are adjustable on a few links, one adjustable type allows you to align the round opening in the expansion slit [like yours] with the rivet to separate, but if yours won't come out then the rivet head is too big and will have to be done with some rivet removal and replacement, I suppose if you could make/optain the correct rivets that one could alter the said band, the tops/caps do lift off after raising the tabs....  
    • This is a watch from a friend who sent it to a neighborhood watchmaker for a battery change. It came back with the watch stem in a ziplock bag and the dial skewed 20°. The watchmaker told him that the stem was faulty and the watch cannot be repaired. I opened up the watch and found that one dial foot was broken off and still stuck in the movement, while the other was bent until it was flat against the dial. The stem could be inserted but it couldn't be pulled out to quickset and time adjusting positions. I did a full disassemble, cleaned and oiled the movement. But when it put in the battery, the second hand runs super fast. Like it gains 30 mins every hour. Any advice on fixing this problem? TIA.
    • I determined that the balance staff is rotating, not the roller table, so my second attempt at riveting was unsuccessful. I have ordered a new balance staff and will take measurements when it arrives. The balance staff i originally ordered (and now reordered) was specified as: Replacement balance staff: (A. Schild Caliber 984 1002 1021 1124 Original Balance Staff Part 723) so it should be correct. Measurements: (see pic below for terminology) xxxyy is a place holder until the new balance staff arrives. Lower pivot: Old - .08 mm New - xxxyy Lower pivot to balance seat: Old - 1.53 mm New - xxxyy Roller shoulder: Old - .42 mm New - xxxyy Hub: Old - xxxyy New - xxxyy Balance shoulder: Old - .86 mm New - xxxyy Collet shoulder: Old - .56 mm New - xxxyy Upper pivot: Old - broken New - xxxyy
    • Hello and welcome from Leeds.  We're here to help. 
    • I was just about to adk that, probably they have unnecessary waiting lists to make their watches appear more exclusive than they actually are.
×
×
  • Create New...