Like most have already said 4 jaw first. I have 2 lathes and Tru set 3 jaw for each, 4 jaw for each, and a 6 jaw Tru set for the Heavy 10. The 4 jaw is on the Heavy 10, 99% of the time. I have an ER32 collet holder and collets in increments of 1/32 (1/16- 7/8) that I can use to hold small parts and center to.0001 on any of the chucks.

Chet

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