Are these the best option for holding drills, or does a better one exist and why? What about for reamers and taps?
I personally use keyed Jacobs chucks for drills, but for reamers, use an ER holder. Taps would depend on whether you are rigid tapping, or have a PCNC or M machine, in which case you would want to use a floating tap head.
so a floating tap head for PCNC?
I use ER collets for all of my usual drills. They have less runout than a Jacobs chuck, cost less than a quality Jacobs chuck and consume less Z-height than a Jacobs chuck.
I use ER collets for uncritical reaming and I have one floating reamer holder for stuff that really matters.
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Ok, so from what I’ve found, a floating reamer holder basically allows the reamer to self-center on the pre-drilled hole. So that minute errors in part dimensions or cad/cam errors or errors in setting the offsets or whatever, effect the final reamed hole much less, compared to a ridged holder like an ER collet?
Correct. With a floating holder the reamer more or less exactly follows the hole even if the spindle is not precisely over the hole. With an ER collect the reamer follows some compromise between the hole and the spindle position. A floating holder is probably overkill for most work on a Tormach.
That makes sense. I’ve reamed a couple of holes so far and noticed that when it initially enters and exits(Z+) the hole, there is audible chatter, but for 95% of the depth it seems to be doing fine. With my limited ability to inspect the final reamed hole, I can’t detect any issues, but if it’s off by a few tenths, that would explain the chatter with a final hole that seems fine.
Thanks for the input, I sincerely appreciate it!