Jump to content

Watchmakers lathe collets


maclerche

Recommended Posts

Then I finally bought a watchmaker lathe that is on the way with the mail. Now I have to buy some collets for the machine!

If money was not a problem, I would ...

Buy schaublin B8 71-137 from 0.3 to 8.0 mm or Bergeon 03 to 8.0 mm.
Unfortunately, the money is not that easy so look for alternatives ..
There are some Chinese sets of all sizes, approx. 77 pieces for approx. 500 pounds. Are they worth throwing money after?
Next option is Vector, which is negotiated by bla. Boley they can be acquired for approx. 38 pounds each.

What do you use and what would you advise ... The machine can take 8mm. B8 or WW collets!

salespic1.jpg

Link to comment
Share on other sites

I quite often see second-hand 8mm collets on ebay. Look out for strained collets, these are ones that have been forced to take a larger size then they should, they will be out of shape. Others I have seen that do not close evenly and have a raised edge around the centre. Rusted ones I would leave them.

I had a watchmakers Boley lathe with a full set of collets, so I never needed to buy.

Thats a nice looking lathe you have.

 

Link to comment
Share on other sites

10 hours ago, maclerche said:

No, it takes "normal" 8mm. watchmakers collets B8 and WW types! 

You can read a'lot more about this machine here https://watchmaking.weebly.com/cowells-90cw.html and here http://www.cowells.com/90cw.htm 

Ok, well I strongly recommend getting an ER collet set if the collets match the standard “Boley” profile.

https://www.ebay.co.uk/itm/282388953876 

Link to comment
Share on other sites

Regarding to ER collets!

The Cowells 90CW (newer ones after 2005) Has a spindle nose with 3 M4 holes. In these holes it is possible to mount an adapter so that the nose gets a thread M14 x1 That way it is possible to mount a chuck. This adapter can be ordered at special dimensions, such as fits a Sherline chuck too and you can get it with center in MT0 And I'd actually thought to get it done so it's a holder for ER8 or ER11 which also features super præsice. The disadvantage of ER collets is that they are designed to hold tools and preferably have material throughout their length or min. 3/4 of the length! A watchmaker collet can hold quite small pieces! But ER is definitely a good option to have too!

http://www.cowells.com/Gallery/CW-headstock.jpg

http://www.cowells.com/Gallery/G13.jpg

https://www.shop-apt.co.uk/er-collets-super-precision-0005mm-runout.html

Edited by maclerche
Link to comment
Share on other sites

ER collets: well, they are very nice to use, and make the choice of collet for the work simpler as they tend to work over a wide range (often 0.5 or 1mm for the smaller types). 

So, I can survive with just 9 collets to cover 0.5 - 5.0mm range. 

Link to comment
Share on other sites

4 hours ago, rodabod said:

I should add that I also own a full set of split collets too. 

ER's can work and might be a solution; many use them on lathe's.  But to compare between them, ER's are for tool holding and split collets are preferred for work holding.   A general view is that split collets hold with better alignment and concentricity than ER's; as ER's were meant for tool holding (TIR matters slightly less)  I won't argue too strongly on that one, a lot probably comes down to the quality of manufacture vs form factor, but I would expect a quality split collet to have the least run out.

The main reason though, is holding shorter pieces.  A split collet will hold work properly with only a short length to grip, whereas ER collets are suppose to be able to grip essentially along their length; they don't maintain alignment or concentricity nearly as well as a split collet with short work pieces....which I would think would often happen.  Again, part of the design legacy as a tool holding collet.

imo its really important to have minimal run out, especially with this small work.  1/2 a thou TIR might be ok on a 2" dia piece, but if you're making a balance staff with a 3 thou pivot, its not.  Precision is expensive, I believe its solidly in the get what you pay for category.  Not wanting to or able to spend $38 per collet, I've always chosen to used ones in good shape made in the developed world: Swiss, German, British, American.  Well truth be told, I've only bought lathes that come with good sets, but these collets are a pleasure to use and not too expensive.  Ebay can be a good source, although I prefer to buy in person so I can see them.  Ebay does have the advantage of the return policy if an unscrupulous vendors ships a set of beaters. 

 

Edited by measuretwice
Link to comment
Share on other sites

  • 2 weeks later...

Interesting and good info.  Do you happen to know if they were referring to the collets which come with their lathe package https://www.ebay.com/itm/New-Unused-Mini-Precision-Watchmaker-Lathe/282991424601?hash=item41e39a7459:g:9WAAAOSwM0FXIAbV

 

or did they refer to these which are available separately https://www.ebay.com/itm/77-Pieces-Collets-for-8MM-for-Watchmakers-Lathe/401089759992?hash=item5d62d00af8:g:-ggAAOSwZ8ZW6fio

 

Thanks

Link to comment
Share on other sites

5 hours ago, mbhorology said:

Interesting and good info.  Do you happen to know if they were referring to the collets which come with their lathe package https://www.ebay.com/itm/New-Unused-Mini-Precision-Watchmaker-Lathe/282991424601?hash=item41e39a7459:g:9WAAAOSwM0FXIAbV

or did they refer to these which are available separately https://www.ebay.com/itm/77-Pieces-Collets-for-8MM-for-Watchmakers-Lathe/401089759992?hash=item5d62d00af8:g:-ggAAOSwZ8ZW6fio

These identical. No different manufacturing for a same product.

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.



  • Recently Browsing

    • No registered users viewing this page.
  • Topics

  • Posts

    • Welcome my friend. 
    • Been there. Worn that Tshirt.  'ping'. Hands and knees. Nothing. Nada. 20 minutes? Ha! I found it 7 month later. How? Well, after advice from a member, I invested in a £4 UV light torch.  Hands and knees looking for a 'ping' from a Sekonda, found them both within 30 seconds. UV makes the jewel shine. easy peasy. Could have taken longer. Just lucky on the location of the search. Hope this helps.
    • Thanks Dell. I thought about silver soldering. Have never done it but would like to give it a go. Do you think to put flux on the butted joint then run the solder in or to maybe brace it with a piece of scrap spring steel?
    • Never and others. Yes, like you I do spend a fair amount of time reading the contents of this forum. I find it better that any other. Clear, lucid, no Prima Donas, and most of all an easy access without adverts. All thanks to Mark. God bless you mate. You give so much to many of us. What if? No Mark? Hypothetically. A forum. I did run a forum for a few years. Really enjoyed it, but became so engrossed that it did affect my health. I gave to to others to run. Not been back. It was very successful and rivalled a number of large paying sites. No adverts, no others but me. I did ask and listen to members comments and it worked well.    Costs Having a domain name, £10 annually.  Register the site with a forum company, free. Build the site using the forum company guide lines, free. It looked and ran almost the same a Mark's. All the same facilities. The cost was only £5 per month, but counted visits (views). If I recall, it was that price for 5,000 views. Each extra 5,000 views increased the price by £2 per month. Success was my own personal undoing. From £5 per month initially, it rose to £60 a month and looked like increasing. This was 10 years ago. I could not afford that, and asked it anyone would like to take over and someone did. I would assume that this is the price that Mark is funding for us all. His return is our continued comments on the internet about his course, and the fact that many of the big names on YouTube mention him as their Tutor. Those of us who have done, and are still using, his course, benefit. In comparison to other courses, I can't believe how cheap it is, and the value is exceptional. It is the structure that gives the value. Long may Mark reign. Ross  
    • Hi all, total newbie to watchmaking and I've had a bit of a mishap. Just completing level 2 and was doing ok, but I was just on the last part of the reassembly of my ST3620 when the balance end stone shot across the room, just as I was trying to see if I had put the correct amount of oil between it and the balance end, aarrrgh! Been on my hands and knees combing the carpet for 20mins looking for it but to no avail. Does anybody know where I can get a replacement from and what to look for please?? Thanks.
×
×
  • Create New...