[underdog]

I'm tapping (and thread milling) in 316 SST. But, the holes that are tapped do vary in depth as the material "pushback force" and the tap "grab point" varies. While our machine is older and needs tension/compression holders, I think there are newer T/C holders on the market that address the varying tap depth issue.

Can anybody steer me to a brand they like? Hopefully not too expensive. Thanks!!

[servtech]

I'm tapping (and thread milling) in 316 SST. But, the holes that are tapped do vary in depth as the material "pushback force" and the tap "grab point" varies. While our machine is older and needs tension/compression holders, I think there are newer T/C holders on the market that address the varying tap depth issue.

Can anybody steer me to a brand they like? Hopefully not too expensive. Thanks!!

A pullout tap holder should not vary in depth, the depth is determined by the feedrate, stroke and number of spindle revolutions.

Are you tapping from a live toolholder?
If so, I have had driven tools motors stalling at low speed due to lack of torque. We had to drill the hole to maximum allowable and plunge in at a higher feedrate.

[underdog]

I'm not familiar with the term "pullout" tap holder. If you mean the collets that have float in just one direction (out) then I guess we could try that. But if you don't feed it at the pitch rate per rev, how do you calculate the depth it will go to? I'm thinking you will feed it less than pitch per rev to let the tap pull itself out but as you said, it's a calculation.