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Hi

I have a rather general question for those who use an 8mm watchmakers lathe. Which collet sizes, or range of collet sizes, would you say you use the most for watch work? It would be ideal to have a full set if possible I would imagine, but that's not likely for most of us.

As collets can only be used for one specific 0.1mm how do you deal with it? Buy each size as required? Cover a core range (eg 5 to 20 or 10 to 30 - those are just made up examples off the top of my head by the way!)? Just buy what you can afford? I'm interested to hear if there are any sizes that are must haves, good to have, rarely used etc. Thanks

Stephen

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On ‎27‎/‎10‎/‎2016 at 6:19 PM, chadders1966 said:

Hi

I have a rather general question for those who use an 8mm watchmakers lathe. Which collet sizes, or range of collet sizes, would you say you use the most for watch work? It would be ideal to have a full set if possible I would imagine, but that's not likely for most of us.

As collets can only be used for one specific 0.1mm how do you deal with it? Buy each size as required? Cover a core range (eg 5 to 20 or 10 to 30 - those are just made up examples off the top of my head by the way!)? Just buy what you can afford? I'm interested to hear if there are any sizes that are must haves, good to have, rarely used etc. Thanks

Stephen

I will be watching this thread closely after my latest purchase.

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On 10/27/2016 at 6:19 PM, chadders1966 said:

Hi

I have a rather general question for those who use an 8mm watchmakers lathe. Which collet sizes, or range of collet sizes, would you say you use the most for watch work? It would be ideal to have a full set if possible I would imagine, but that's not likely for most of us.

As collets can only be used for one specific 0.1mm how do you deal with it? Buy each size as required? Cover a core range (eg 5 to 20 or 10 to 30 - those are just made up examples off the top of my head by the way!)? Just buy what you can afford? I'm interested to hear if there are any sizes that are must haves, good to have, rarely used etc. Thanks

Stephen

That is really difficult one to answer because speaking from experience I never seem to have enough collets. I have a swiss made three jaw chuck which is not ideal but that is what I have to use. The problem is that a chuck is not as accurate as a collet. I read somewhere that the four jaw chucks are better but they are lots of money. If I was to purchase again (if I had the money that is) I would purchase a lathe with a full set of collets.

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I would probably start your set with the following numbers (note that the size increments are 0.1mm, so a #4 is 0.4mm): 4,5,6,7,8,9,10,12,14,16,18,20,50. You might also add 16,32 and 48 if you want to work with stock as these correspond to 1/16", 1/8" and 3/16". This set should cover most of what you will need to do. Then you can add as you need other sizes.

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On 10/27/2016 at 1:19 PM, chadders1966 said:

Chedders,

I am a firm believer that the smaller watchmaker lathes are best suited for small parts.  WW collets have very little range and should closely match the part being gripped. I feel, therefore,  that the best approach is to have as complete a set as possible up to about 1/8th of an inch. I have found that machining larger parts requires a larger lathe (such as a Taig) that offers more size, power and rigidity. 

david

 

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51 minutes ago, david said:

 

Your right, it is most important to have the correct size and correct collet for the task in hand. If you use a watchmakers lathe you don’t work on it for clock parts, it wasn’t built for such work. You need a bigger lathe.

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  • 4 years later...

Another option that most watchmakers would not consider would be to use a wax chuck for turning.  Covering all of the sizes with collets requires a complete set of metric and a complete set of  inch collets.  I believe Sherline still manufactures WW collets   Collets are a quick and convenient way to hold a shaft to be turned, but are expensive and slightly less accurate than a wax chuck. 

 

Wax chucks are not that difficult to set up and cover every size.  If set up properly they can position work to extremely precise tolerances.  All that is required is a #50 WW collet and a piece of brass rod to fit into the collet.  You then face the brass rod,  cut a cone into the faced end,  and fill the cone with hot shellac. Insert the part to be turned into the hot shellac.  As the shellac cools, rotate the lathe spindle and center the part with a small piece of wood; such as a matchstick.  When the shellac hardens the part will be securely held and will run absolutely true.

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