Greetings everybody; I just came in from putting the finishing touches on that MT5-5C adapter I bought from Grizzly, finding it wasn't the MT5 my sheldon wanted as its called a short MT5 in the spindle description.
First. I had to regrind the MT5 in the spindle as the spindle was bent, around 7 thou at the mouth, I assume from the sudden stop with a chuck mounted in the same fallover that demolished the compound. Got that fixed but then tried to clean up the adapter I got with the lathe, which was obviously a shop made part that was never compared to a 5C drawing. The inner bore was all over for size, the taper seat angle was maybe 8 degrees. So I bought another from Grizzly. I took around 2.25" off the small end. then bought some 1.75" alu rod and made a short MT5 on one end, but threaded for the drawbar tubes threads on the end. Then I turned it around and pulled it solidly into the spindle and carved a 5C profile on the other end, overshooting the small end cut by about 2 thou, shloppy fit. Cleaned it up, cleaned up a knurling tool and gave it a crosshatch about 5 thou tall. filled crosshatch with permatex liquid metal. Gave that a day to harden and cut it back to the right size. Grizzly part, turned end for end, seated well, so I set the grinder back up and ground it to an MT5 taper whose big end was about a thou bigger than the mouth of my now slightly larger spindle. Measured how deep the short MT5 was, and shortened it to about 1/8" less. Then on putting it into the spindle and starting the spindle and from the contact pattern on the ER-40 adapter telling me it wasn't ground to a 10 degree angle, but it was obvious, you could see it from 6 feet away, that the tapered section the ER-40 was supposed to seat in, was eccentric by a measured 16 thou! So I cleaned it and the spindle, seated it in the spindle, drove it in with a dead blow, set up the grinder and made that both concentric and 10 degrees. Mouth of ER-40 adapter run-out now about .00012". Unwrapped the new nut, (the one that came with the adapter had 20+ thou wobble in its seating cone) a ball bearing type, cleaned it up, unwrapped a 1/2" collet, and stuck a 2' piece of A2 in it. Drew it down with the wrench I bought with it, then gave the wrench a couple whacks with a deadblow. Dial says .0001" on the A2 at the collet, and .0004" an inch from the collet. I think that calls for a minor celebration. Makes for a VBWGrin anyway. Moving the dial with the carriage also tells me the head on this thing isn't well trammed. The error, assuming the A2 isn't tapered, is about a thou/inch. What sort of a measuring setup does it take to measure that? But so far my work to correct the bent spindle has I think been successfull. I not touched the outside of it. but I have the new 4 jaw chuck running within .0006" of true, and some of that may be warpage from tight mounting bolts, its a very noisy .0006". And I will do the same backplate cleanup on the 3 jaw. I'll make a real lathe outta this $2000, 1500 lb pile of scrap yet! ;-) Thanks for reading guys, comment if you like. -- Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> ------------------------------------------------------------------------------ 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
