Jump to content

Acquisition of Jewels/OD/Hole Diameter, Etc.

SparkyLB

By SparkyLB
in Watch Repairs Help & Advice

 Share

Recommended Posts

SparkyLB WRT Addict

SparkyLB

Posted
Posted (edited)

I can measure the OD of a jewel if out of the mainplate with a JKA Feintaster, or appropriate micrometer.  I'm fairly sure there is a tool (is it called a pin gauge?) to measure the pivot hole size.   

What I can't seem to find info about is, what if need a certain size jewel (outside diameter) with a certain size hole?  Below are two educated guesses:  Am I on the right track?

1.  I'm thinking jewels are acquired that are a bit large and the mainplate is broached to an appropriate size for the jewel to be pressed and depthed?  (speaking of friction-fit; I'm aware that there are jewels contained in bushings that shoulder to mainplate--but I'm not referring to those.)

2.  As far as the pivot holes, I'm guessing that this is something that is not changed (unless using a lathe and micro drill bits?) and one sorts through many jewels until an appropriate size is found, then back to step one?

Finally, are jewels purchased in lots on eBay, or are they purchased by caliber/movement number?  I've looked on eBay for weeks.  There's no shortage of pallet entry and exit stones, but there is a distinct lack of round jewels for wheels.

Thank you all.  Forgive me if some terminology is incorrect.  I'm still somewhat a beginner.  

Edited by SparkyLB
brevity is the soul of wit.
Link to comment
Share on other sites
watchweasol Distinguished Member

watchweasol

Posted
Posted

Hi   Regarding jewels they come in a lot of different sizes and as far as I am aware three types of setting, some are friction fitted using a seitz jeweling tool, some are in a brass setting and are screwed in and some are rubbed in. The rubbed in variety require special tools to remove broken or chipped jewels and a tool for rubbing in the new jewel into its setting.

There are assortments of jewels on ebay but it means sorting through and trying each one to find the correct fit, If you know the calibre and make and find the part number for the jewel then you are sure you get the correct size. The thing to do is to measure the pivot requiring the jewel then either order the same. Or if you are lucky enough to have phials of calibrated jewels select the correct size 

  • Like 1
Link to comment
Share on other sites
Alaskamick WRT Addict

Alaskamick

Posted
Posted

You could buy drill bits from Cousins, they go from 0.5m to 2.00 mm.

These are jewellery drills but there are all types available, you would need to gently feed the drill through until you get to the shank witch will be the size of the hole.

Never having looked for jewels I'm not sure what the hole size would be.

  • Like 1
Link to comment
Share on other sites
vinn3 Distinguished Member

vinn3

Posted
Posted
2 hours ago, Alaskamick said:

You could buy drill bits from Cousins, they go from 0.5m to 2.00 mm.

These are jewellery drills but there are all types available, you would need to gently feed the drill through until you get to the shank witch will be the size of the hole.

Never having looked for jewels I'm not sure what the hole size would be.

    twist  drills shanks can be sliped into the hole for an aproximate I. D..    vin

Link to comment
Share on other sites
SparkyLB WRT Addict

SparkyLB

Posted
  • Author
Posted
3 hours ago, vinn3 said:

 

     the best tool for measuring a hole is a "ball micrometer".    you could make one via lathe.    i don't think one that small can be found.   vin

Thank you, vin.  I'll have a look at these implements.  I think I've seen spring loaded pin-type tools with a display not unlike a thermometer, and depending upon how deep the tapered pin enters the hole, the graduations on the stationary part tell the diameter.  

3 hours ago, watchweasol said:

Hi   Regarding jewels they come in a lot of different sizes and as far as I am aware three types of setting, some are friction fitted using a seitz jeweling tool, some are in a brass setting and are screwed in and some are rubbed in. The rubbed in variety require special tools to remove broken or chipped jewels and a tool for rubbing in the new jewel into its setting.

There are assortments of jewels on ebay but it means sorting through and trying each one to find the correct fit, If you know the calibre and make and find the part number for the jewel then you are sure you get the correct size. The thing to do is to measure the pivot requiring the jewel then either order the same. Or if you are lucky enough to have phials of calibrated jewels select the correct size 

Thank you, watchweasol.  You answered the question regarding can jewels be ordered by part number, i.e. calibre.   

3 hours ago, Alaskamick said:

You could buy drill bits from Cousins, they go from 0.5m to 2.00 mm.

These are jewellery drills but there are all types available, you would need to gently feed the drill through until you get to the shank witch will be the size of the hole.

Never having looked for jewels I'm not sure what the hole size would be.

Thank you for the resource, Alaskamick.  I'll get some of these for sure.  I'm guessing they ain't cheap!

11 minutes ago, vinn3 said:

    twist  drills shanks can be sliped into the hole for an aproximate I. D..    vin

Absolutely.  

 

Thank you all for replying.  I'm putting back together a very old orphaned movement, and the jewel hole for the 3rd wheel (not a seconds wheel in this case) is badly broken, preventing the train of wheels to be driven; at least downstream of the center wheel.  

Link to comment
Share on other sites
 Share
Go to topic listing


  • Recently Browsing

    • No registered users viewing this page.

  • Topics

  • Posts

    • JohnR725
      Omega cal. 565 - low amplitude

      By JohnR725 · Posted

      can I ask why you're not happy? did you notice that the acceptable low 24 hour amplitude of this watch is 160°? is there any possibility that a watch company could manufacture a watch that could actually run at a low amplitude and keep time? so if they can run at 160° at 24 hours and keep time then they probably would keep time at 240° which yours seems to be doing? then if you're really unhappy with this I would recommend purchasing an original Omega mainspring. Just because the aftermarket have numbers like an Omega mainspring it doesn't mean it's the same thing. Then I would also recommend replacing the escape wheel and the pallet fork. This is what they do in the Swatch group service center if they are unhappy with anything on the other hand they have an infinite supply of spare parts.    
    • Neverenoughwatches
      Without Our Forum

      By Neverenoughwatches · Posted

      That was reason for asking for mark's input, i wasn't sure if going ahead with dealing with the contact information would be particularly well received. @oldhippy thoughts ?
    • RichardHarris123
      Omega cal. 565 - low amplitude

      By RichardHarris123 · Posted

      @JohnR725 has pointed out many times that the Swiss don't care about amplitude, the timekeeping is the most important.  Give yourself a  pat on the back, great beat error and timekeeping, nothing to be disappointed about. 
    • RichardHarris123
      Without Our Forum

      By RichardHarris123 · Posted

      I'm bothered but I agree he's a busy man and I don't want to bother him.  In the meantime, we really do need to have other ways of contacting each other  
    • RichardHarris123
      Second hand watch market.

      By RichardHarris123 · Posted

      This is as complicated as epilame, too many unknowns. The life expectancy in the UK is circa 80, so most people from 1944 or earlier are dead.  Assume they had children at circa 20, they died in 2004. Their children started selling 1944 watches in 2004, so pre-1944 watches must be getting more rare.   It doesn't work though because as you stated some were sold as tat, but since watch prices have increased people have decided to sell when they may not of done in the past. 
×
×
  • Create New...