Jump to content

Trying to identify some 8mm ring and step collets...

nw10
 Share

Recommended Posts

nw10 New Member

nw10

Posted
Posted

Hi,
I bought a Boley 8mm lathe on eBay which came with some ring and step collets but unfortunately they don't fit the lathe. Judging from appearance they may be from 2 different manufacturers. They don't have a makers name and I hope they will look familiar to someone?
Thank you.

20210602_132654.jpg

20210528_200958.jpg

20210528_201721.jpg

Link to comment
Share on other sites
LittleWatchShop Distinguished Member

LittleWatchShop

Posted
Posted (edited)

How is that they do not fit?  Do they not fit at all into the spindle?  Do they fit in the spindle, but only so far?  Do they fit all the way into the spindle but do not interface with the draw bar?  Do the threads fit the draw bar when outside of the spindle? Can you show a measurement of the diameter of the collet?  Is there a key in the spindle but it is too wide for the key clot?  Have you fit a standard collet into the spindle?

My computer does not work.  What is wrong?

Edited by LittleWatchShop
Link to comment
Share on other sites
HectorLooi Distinguished Member

HectorLooi

Posted
Posted

I've come across a few ways that a collet might not fit.

The collet might be the "long" type, where after tightening the drawbar all the way, it's still loose. This can be solved by putting washers on the drawbar until the collet can be tightened.

Another way is the collet is too short that the drawbar cannot engage the threads. It might be possible to lengthen the drawbar or buy a longer drawbar.

Thirdly, the threads might not fit. I'm aware that China made lathes use a different thread pitch for their lathes. Although it's also 8mm, they won't fit a WW 8mm lathe. I'm not sure if buying a China made drawbar will solve this problem.

Good luck!

  • Like 1
Link to comment
Share on other sites
nw10 New Member

nw10

Posted
  • Author
Posted

Thanks both.

One of the step collets is just too big to fit into the headstock. It measures 7.8mm diameter at the level where the slot starts compared to 7.75mm at the same place for the Boley.    

The other 2 step collets fit into the headstock but the drawbar / spindle only will only tighten half to one turn. The screw gauge on both collets is 40 Whitworth (same as a Boley collet). But the external diameter at the threads is 6.99mm compared to 6.83 of the Boley.

Maybe a Chinese drawbar would work. I tried looking on ebay but could not find one...

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.
Note: Your post will require moderator approval before it will be visible.

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
Go to topic listing


  • Recently Browsing

    • No registered users viewing this page.

  • Topics

  • Posts

    • RichardHarris123
      Setting lever spring

      By RichardHarris123 · Posted

      I'm assuming that every time you set the watch you are work hardening the detent spring, maximum hardening is  where it meets the plate due to maximum deflection.   That's why it snaps there.  The Young's modulus may be the same but after it's reached its maximum yeid strength it breaks.  My mechanic engineering is very rusty, correct me if I'm wrong. 
    • Neverenoughwatches
      Setting lever spring

      By Neverenoughwatches · Posted

      Ah ok yes that makes sense to polish it where the arm starts to form from the body of the bridge, i thought you meant the underneath of all the arm.
    • JohnR725
      Epilame / Fixodrop

      By JohnR725 · Posted

      this is something I've never quite understood about the some of the Swiss companies. In 1957 Omega was using 9010 for the keyless parts with epilam. there's been a slow migration towards using heavier lubrication's but still typically oils and epilam to keep them in place. When it seems like 9504 works so much better.  
    • nevenbekriev
      Is this a 'hack' ?

      By nevenbekriev · Posted

      OK, welcome in the world of alarm clocks... I guess the 4th wheel is dished because it is from another movement. If it was not dishet, then it would not mesh with the pinion of the escape wheel, am I right? The marks of wear on the 4th wheel pinion doesn't corespond to the 3th wheel table position, at list this is what i see on the picts. Calculating the rate is easy - there is a formula - BR = T2 x T3 x T4 x T5 x 2 /(P3 x P4 x P5) where T2 - T5 are the counts of the teeth of the wheels tables, and P3 - P5 are the counts of the pinion leaves. Vibrating the balance is easy - grasp for the hairspring where it should stay in the regulator with tweasers, let the balance hang on the hairspring while the downside staff tip rests on glass surface. Then make the balance oscillate and use timer to measure the time for let say 50 oscillations, or count the oscillations for let say 30 seconds. You must do the free oscillations test to check the balance staff tips and the cone cup bearings for wear. This kind of staffs wear and need resharpening to restore the normal function of the balance.
    • RichardHarris123
      Any tips to correct a sloppy error?

      By RichardHarris123 · Posted

      Glue a nut to the barrel lid, insert a bolt, pull, disolve the glue.  Maybe someone will have a better answer. 
×
×
  • Create New...