Holding screw-end end-mills/slot-drills

And therein lies the problem. An aged model engineer into his seventies is unlikely to be able to tighten as much as someone in their fifties. Which could be why we get the tails of woe from more senior members who swear by their Autolocks and swear at their ERs

And don't forget us girly weeds! Charles Atlas used to kick sand in my face.

But even though I'm a weakling well past his 'Best Before Date', I've not had ER collets slip on me. Nothing special done - I tighten them with the supplied C-spanner and a home-made 38mm, both about 7" long.

Dave

More torque less force required? Even a weakling girl can work on most things with the right tools 🙂

And she's unlikely to rupture herself due to macho posturing! Don't ask how I know...

Brain muscle is all you need 🙂 x

I don’t see a problem with adding some length to the tightening gear for your collet chuck, anything that makes life a bit easier has to be recommended. Unfortunately we don’t stay as powerful as we were at age 25 or probably as fit. Working smarter not harder has to be the way to go.

Mike

Yes I've got no brawn with doing anything handy. I can't open jars but wearing rubber gloves I can, more about grip than strength 🙂

The length of those specially made ER spanners is not random: The length is chosen based on the required torque and what they consider a normal use of strength for tightening. If one can't reach that strength, or just want it easier, just put on a suitably long extender to compensate. The length does give some indication of what it requires though.

Another option is to use the "ER Collet Nuts with Ball Bearing - Type B" as sold by Arceurotrade. I use ER25 size collets and I have never had a cutter move, slip or come loose even when taking some fairly heavy cuts and that's just using the standard C spanner. As to age on the high side of 75 and that's me not the mill. Standard disclaimer re Arceuro, just another happy bunny.

Marttin

What I'm learning is having the right tool for the job is more important than strength?

Mostly correct, although the real skill is knowing when BF&BI and a bigger hammer are the right solution.

Andrew

I always take the ER chuck out of the mill and hold it in a bench vice to tighten. And as noted earlier, use an extension on the spanner to apply enough torque to tighten.

Paul

I think the ER chuck is primarily a device for automatic machines where the tooling is set up away from the machine, it has found a place as a very useful general purpose cutter and work holder although these are probably not its original purpose. Changing cutters while leaving the chuck mounted in the spindle needs either a two spanner approach or a substantial spindle lock capable of coping with the recommended tightening torque of the collet nut. Most of us probably give it a good pull and leave it at that and most of the time it will be ok, when our good pull on the standard length spanner is our best effort but not enough then trouble may be on its way. Most spanner’s are of a length that a man of average strength will not over tighten the job, of course there are people with gorilla strength and people who need more time with their Bullworker, I suspect that a professional tool setter will use a torque tool or experience to tighten a collet. The ER collet having a range of perhaps 1mm may be asked to grip a 6mm cutter in a 6-7 collet, this is not the most effective option for maximum holding power. When the optimum conditions are met the ER system has phenomenal grip and a cutter moving even under the most arduous conditions is unlikely, failure to meet the recommended parameters leaves a risk of failure.

Mike