Hi All,
I recently purchased a collet chuck to use in my mill. I have a lathe/mill combo and the distance from the mill head to
the cross-slide is just a bit more than an endmill mounted with a collet directly in the spindle. The collet chuck adds
another 1.5" or so and comes with tiny collets to hold some engraving tools (3/32") that I want to tinker with.
Unfortunately there appears to be a great deal of runout in the chuck itself. If I mount an endmill in any of the
collets and run a dial indicator at the non-fluted based of the endmill there is as much as .005" of runout. By the
time this is extended to the end of the cutter, there is a noticeable wobble that makes the cuts much wider than
the tool bit. I assumed it was a poor quality chuck (eBay
), but I see this set from Smithy
http://www.smithy.com/ecom/detail.asp?n=Spring+Collet+Chuck+Set&sc=MILL+%26+DRILL+SETUPsays concentric to .005". That's pretty crappy even for my less-than-perfect equipment.
I would try to true this one up a bit, but I'm not sure how to go about it since I can't clamp it true in my lathe
(no taper in my spindle, just a 3" jaw chuck). I thought about mounting a cutter upright and bringing the mill head
down on it to center the taper, but if the collets are also bad I see no way I am capable of fixing them.
Does anyone know of a source that sells a more accurate collet chuck? It seems like a great solution for me as it makes
tool changing relatively quick, doesn't requiring hammering on the drawbar against my Z-axis drive, and gives me my
needed extra length to reach thin plate directly on my machine bed.
Thanks for any input!