I need to use two 3J collet chucks (true length made by ATS) to make a part. Unfortunately the one I pull out from another Nakamura has different joint(element to connect chucks body with the draw tube). Is it possible to buy one somewhere or I need someone to make it for me. Thank You for any answer.
ats whould be able to supply the spindle tube adapter for your machine to there collet chuck, or you can make one its very easy.
for the most part you need to give them the machine modle number as most of the collet nose makers will know the spindle tube thread size and length needed.
if you have to make one you will have to measure the thread on the spindle tube.
as far as the length bolt to nose to the machine and use a pair of calipers, you can be with in a 1/8 of an inch or even more. tolorance isnt that important.
on a new machine I always make the spindle tube part first then thread it onto the machine bolt the nose to the machine and check the distance to the face. then cut face of necc.