Regarding the drawbar and gripper, did you make it yourself and do you have picture of it? What ballsize do you use?
I have build a 6x5mm ball gripper but I get dents on the pullstud (using 45deg) and don´t know if this is normal since it could affect runout I assume.
I´m using about 800pounds of force from bellevilles springs.

I also have a VFD with 2 pole 3-phase engine and planing to use index signal to orient the BT30 holder. Can you provide more detail about the shot pin, picture of it would be super?

Nothing special on the gripper. Just the same 4 ball that everyone else has done. I'm using .187" balls and about 1000 lbs of pull. I just checked my pull studs and I have no signs of wear.

My mill has a step pulley. I'm using a small pancake cylinder. It was double acting so I took it apart and added a return spring. No chance of it coming down unless it's told to. The rod came drilled and tapped for an 8/32 bolt. I cut the head off of the softest screw I could find and screwed it in the cylinder rod. That way it MAY shear off if there is a problem.

Looks like 14.2mm then opens up to 17.5mm to accept the shank of the nt30 (17.00mm)

Are you guys running those sort of revs with the vari speed heads or pullies?  I have turned up my inverter 10hertz above standard and to be honest thd vari head doesn't sound like it enjoys it to much so turned if back down.

I don't think 14mm is a large enough diameter. The pull stud head is 11mm. It may be possible though. If you give me some complete dimensions I'll plug that into my model and see how it looks.

I'm using a step pulley.

Derek

What type of pull stud do you use with ball gripper? 45deg?
I'm using 45 deg from ctc toolz and have clear marks with less force than you.. Hmm

What type of pull stud do you use with ball gripper? 45deg?
I'm using 45 deg from ctc toolz and have clear marks with less force than you.. Hmm

I'm using a 45 degree. I mostly use the ones from Mari tool

Thanks for your answers, how about the shot pin arrangement for spindle orientation? Pictures would be great, since i can´t see it on the other pictures?

That small cylinder next to the aluminum rod in the picture above is it.

how does the shot pin idea work ? thanks Mark Moog madness