Question about Dremel 400 Series Xpr Rotary Tool Kit with Xpr Multisaw and Xpr Planer Attachment 400 - 6/90

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Can't unscrew collet

Trouble with Dremel 400 XPR
Can't unscrew collet - even with wrench. While depressing the blue button (as instructed to do whether tightening or loosening), the threads seem to simply run right over the engaged stops - preventing the ability to loosen the collet.
I finally managed to get it off: but to prevent a repeated scenerio, do I need new parts or just maintenance?

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It is possible that you stripped lock mechanism on the collet, for the beginning, never, ever, use wrench to tighten the collet! just hand tied, if it slips, tight it bit more, but with hands only.

i never used wrench on the collet and never have any trouble with any of my dremels.

to close, just hold firmly in one hand pressing locket button, tighten up with other hand, to undo, reverse procedure.

if you find bit is too lose, then you have collet inserts, find that one which hold bit firmly and use it on this particular bit. standard collet is 1/8" (3.175mm), but in the set there are collets from 0.0394'' (1mm) to 0.177" (4.5mm). do not use wrench...

just inspect now if thread is not stripped, on spindle and on collar, if locket still hold, if these are damaged, you need to change damaged part. and follow the advice :-)

if you find this advice useful, pleasae do not hesitate leave your remark and vote4 for me, thanx!

Posted on Aug 02, 2010


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