[ScottDW]

Any advice on what to look for in a used SL15 with turret?

[tmarks11]

Any advice on what to look for in a used SL15 with turret?

Index the turret repeatedly and measure the X/Y positions of the tip of the tool. There was some problem with the first generation turret; can't remember if it was a reliability or a repeatability issue.

Do some test cuts, and mic them to see how close to the programmed cut they end up; this will give you some idea of backlash.

When was the machine originally purchased?

Look for indications on the turret, QCTP (if fitted) and chuck for any crashes.

[MichaelHenry]

I second the recommendation to check the turret out thoroughly, especially if it has the Rev 1 turret. Mine has that turret and I've had periodic problems with repeatability in "X" when multiple turret stations are used in one job. I'd guess that worst case might be a 0.001" or a bit more off in X. That's not a problem for most jobs unless you have a demanding customer. I'd also check the repeatability of the homing switches - mine varies +/- 0.020" in X and a few thou in Z. Variability of the homing switches is a minor annoyance rather than a show stopper since you can always re-zero the work.

On edit: I'd also try turning collars on a long work piece to see how much taper the lathe has in X. Googling for Rollie's Dad's Method should turn up something useful. Also the 4-part series on checking out a a CNC lathe starting at this link might be useful"

https://www.youtube.com/watch?v=yFUlBtfbpEM