On 13.01.18 19:59, Gene Heskett wrote: > I did get the mt5-5c adapter running pretty true, about half a thou of > runout in the bore of an ER-40 adapter plugged into it, but the nut on > the ER-40 is absolute trash. You can see it wobbling, and it pulls the > nose of a collet sideways so bad the runout is .0045" at the front of a > collet. And I haven't a clue how to polish that back out of its > off-centered cone in the nut. Chinese crap. But I've so much (>$200) in > the whole kit, I've got to throw even more money at another nut. 50mm > x1.5 threads. Even the half spanner that came with it is way small. But > that isn't your problem of course, I'm just crying in my nightly bottle > of Miller64. ;-)
There are a few reviews of Chinese collet chucks on youtube. The two I've seen measure chuck internal taper runout similar to your experience, Gene. (The outside's OK, but the bit that counts is poor.) Once one of the Chinese collets is inserted, all bets are off, and it's best for woodworking. One review showed one of the ostensibly ER32 collets in the set was over 33mm in diameter, and couldn't be inserted in the nut in half a minute of wrestling. Another video shows a Chinese collet chuck's internal taper being ground. Nowhere have I seen anyone use one as-is. It appears to be best to remember how _much_ cheaper they are, and then consider why. I wouldn't buy 'em, except as a kit to grind to tolerance, chucking out the collets beyond rescue. To attempt a rescue, maybe skim the chuck internal taper, then hone it? The chances of making it worse are slim. If it works well, there's a very handy youtube video in it. Erik ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
