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3AT collet set

trlvn

Ultra Member
Offering a set of 16 3AT collets from 1/32 to 1/2 inch together with a Morse taper 3 adapter. Asking $75 OBO.

Overall.jpg

My understanding is that these were designed to work with an Atlas or Logan lathe with a MT3 spindle. Missing is an appropriate draw bar/draw tube to tighten the collets. I got these in an auction lot--let's just leave out the sad sorry of a crappy description and even worse photos! The following shows a collet in the adapter compared to a MT3 arbor (not included).

Adapted collet v MT3 arbor.jpg

Collets are all "Burnerd Made in England" except the 1/32 and 3/32 size which are marked "Royal". Collets are a bit dirty but otherwise appear to be in good condition. No obvious dings or burrs. Wooden storage box included.

markings.jpg

Given the very small sizes, I think these might be very useful for someone doing small scale work. Models, clocks, precision instruments, etc. A random posting on the internet suggested doing carburetor needles! Again, note that you almost certainly have to make or buy a draw tube to use these.

Located in Oakville, ON. Shipping at cost. The net weight including the user-made box is about 2 kg. The box is about 0.8 kg by itself.

Craig
 

trlvn

Ultra Member
These are very similar to 3C collets. The body is bit shorter so a longer draw tube is required. I use 3C and a 3MT adapter on my 9”Southbend. Here’s a table showing the dimensions
https://web.archive.org/web/20130505163827/http://shopswarf.orconhosting.net.nz/collet.html
Thanks! I believe that 3AT and 3C collets also have a different taper angle. One drawing I found suggests the included angle for 3AT is 30 degrees while 3C is 24 degrees. I haven't tried to measure anything to verify.

Craig
 

Johnwa

Ultra Member
Thanks! I believe that 3AT and 3C collets also have a different taper angle. One drawing I found suggests the included angle for 3AT is 30 degrees while 3C is 24 degrees. I haven't tried to measure anything to verify.

Craig
You are right the taper is different.
 
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