Kram
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I disagree there, all the cheap ones I had were very good unlike the toolpost I got from arc... They are just importers like everyone else.I’ve been switching back and forth with the idea of 5C vs ER40 myself, not really come to a decision.
If you are going to buy an ER chuck, I'd suggest looking at the ones from Arc Euro - from what I've seen, they seem to be better regarded for QC, and the guy stands by them and will sort out a replacement if you get a duff one with a load of runout, which seems to be quite common with these cheap ER chucks.
The other thing I've seen mentioned quite a bit is that the cheap 5c collets tend to be pretty good and consistent, whereas the cheap ER collets are very much a lottery.
I believe the 5C typically have better TIR than the ER unless you pay for extra precision versions. Overall I think ER is a better system, but it is possibly less clearcut at my level of budget
ER's main advantage is to clamp a range of sizes, you dont need a close sized collet, this is a massive help on a lathe, Ive never considered buying a 5c set for that reason.
That is what I thought.
I have a Jacobs rubberflex on my Triumph. I fine tune it to about a tenth. Get about 3 tenths on a piece of ground steel.
My 5c hardinge collets on my Feeler lathe about the same.
I thought you could machine something. Take it out and carry on where you left off bit not in my case.
As a result I have gone back to the 3 jaw for most things on the Triumph.
On the feeler it's all collets. I was lucky to get loads Inc hex and square. All genuine Hardinge ones.
When mine was set properly I was getting 0.005mm - 2 tenths when reinserting which is very much the limit of the lathe bearings, chatter and roundness. Maybe you were expecting too much but its enough to turn a part around and not see the join, well within the runout spec of my cheap collets.
If you want it to be 100% dead on, put a punch mark so that you can exactly align the chuck body to the spindle. Take a cut on the body OD so that can be indicated. Then recut the taper. Its ok to indicate compound from existing taper, just dont cock it up by indicating off centre like I did.. until I redo it, my reinsertion runout is upto 0.2mm So I am careful to do parts in a single operation when I can. Its on the list to turn a new, better collet chuck.