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As the title says, I have a collet chuck that came with the mill... but I have no idea what sort. Its MT3 taper, can handle anything up to 0.7" (17.7mm) through the nut and the internal opening for the collet in the main body is 22.4mm at the top. The nut is about a 32mm thread. The outer dimensions are 48mm dia and from the top of the nut to the gauge line is 66mm....
Ideas?
I got a screwed shank milling cutter imperial collet set with mine. I keep a handy reduced shank 3/4" cutter in it, but for everyday I use ER32, cheap and convenient.
Quick reply, still a distinct lack of smileys. glum
Could be a Clarkson, does it take standard end mills?. Is there a pointed dimple inside the body at the top?.
Yes, there's something that looks like a little centre in there.., here are some pics...Quote:
Originally Posted by fisherjim
That's the one...Quote:
Originally Posted by irving2008
Screw the nose shut, it doesn't grip until the cutter is in place. Screw in a milling cutter until it hits the pin, open the nose slightly so you can screw the cutter in another quarter turn then tighten the nose.
Don't screw the cutter in too far, smaller sizes can shatter if not supported by the threads because the nut drives against them.
Hmmm, I dont understand - what does the cutter 'screw' onto, there's no thread as such inside...Quote:
Originally Posted by Robin Hewitt
[edit]Ah - I see... its a Clarkson Posilock.. uses threaded tanged collets... so I need to buy a set of collets at £35 then some special threaded endmills at £5 - 8 a go...
Should I maybe just go get an ER25 or ER32 collet set...?[/edit]
So you didn't get the wooden box with chuck, spanner and set of four Imperial collets then?Quote:
Originally Posted by irving2008
No great loss, compared to the ER32 I now use, it's a piece of dung. Millling cutters from yesteryear only.
I tried inserting a bolt in the back of the 1/4" collet to give it something to press against so I could use an unthreaded cutter, but it didn't have the grip.
Thats all the argument I need to go buy an ER32 chuck with collet set from RDG or Chronos...Quote:
Originally Posted by Robin Hewitt
Thinking this through further... my lathe has an MT3 taper also would it make more sense to buy:
ER32 MT3 Collet set
or
MT3 Collet set
Whats the advantage/disadvantage of the direct acting collets?
MT3 collets will reduce the overhang but I don't think they are so keen on intermediate sizes like ER32 which has a much steeper taper and slots from either end. Could be wrong, usually am.
If you go ER32, I prefer the spanner with lots of teeth rather than just one. Can't slip off. Alternatively a long spanner for the top so you can brace it against the column. Just avoid heaving on two spanners at the same time if one of them isn't 100% secure, saves unexpected leaps backwards or heads colliding with milling machines depending on which way you are turning it.
When I started using ER32 I didn't realise you were supposed to hook the collet in to the nose before you put it on the chuck. Nice feature because they eject. Had to break one to find out. :rolleyes:
If you buy ER32 check the run out as soon as it arrives. Run out is part of ER32 spec so if yours exceeds the stated tolerance you can send it back, not as advertised.
Nice to have the whole set, but most of my set are still virgin and untouched. The 7-8mm has lost it's shine along with a few of the smaller sizes. I find CNC usually requires a smaller diameter cutter because my software won't adjust the internal radii to rough out with anything big. I keep a 3/4" reduced shank cutter in that Clarkson for top facing.