On Sat, 15 Dec 2007 22:20:31 -0600, Louis Ohland
wrote:

The CQ6128A lathe has an MT4 spindle bore and a 1.5x8 threaded nose. The
inner diameter of the bore is 26mm. I'd like to use ER40 collets with
this if possible, where I can pass stock into the bore. Yes, I have seen
the MT4 ER40 chucks on ebuy.

5C are 1.25 (or bigger) at the base. 3C collets go to 3/4, but they use
a drawbar. 5C collet chucks only add about an eighth inch over ER40, so
there's no extra cache to them...

Ace Eurotrade makes an ER32 collet chuck, but no ER40.

What exactly are you intending to clean up?
The MT4 taper is nothing like that on an ER40 collet. The closing nut
thread is nowhere near your spindle nose thread either.

Why can't you just machine the ER collet holder with your lathe from a
suitable hunk of steel? No need for a reamer just use the compound
slide and a sharp tool.

I think another UK supplier do ER40 backplates, maybe Warco or
Rotagrip.


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