On Monday 02 April 2018 21:33:22 David Berndt wrote: > What? What exactly is the pitch/sizing on a USS bolt? Google doesn't > really return much for a USS thread chart... UNS? 7/16-18? TSC was > formed in 1938, perhaps you got their last piece of original stock?
Their drawer marking is still old style, uss & sae. When they actually label it that is. Eeecks! They changed the designation when I wasn't paying any attention, one of the hazards of reaching my over-ripe age I guess. At <https://en.wikipedia.org/wiki/Unified_Thread_Standard> Nowadays it appears what used to be USS is to be called by "UNC" (14 tpi for a 7/16") and SAE is to be called "UNF" (20 tpi for a 7/16"). Ack wikipedia, there is also a UNEF (28 tpi) but I've not seen one of those critters in my 83 years plain enough to remember it. Its likely a good thing you called me on it, else I would have carved a hunk of A2 to 18 tpi tomorrow. And it still would not have fit. But now I'm curious, do I have metric threaded R8's? The 14 screws in a few degrees over a full turn before it jams. But the R8 is Bridgeports pet tool holder so I assumed it was an American bolt. And taking this one out of the G0704 is, shall we say, a "project" thats is not going to happen unless it fails. So I'd better get out my taps and see how a 10mm coarse thread fits in one of these, I might have a crossbreed of some sort. If you hear muttering from North Central WV by the time the weather passes by tomorrow, you'll know why. Thanks for the gentle reminder. I think you may have saved me from making a mistake. > On Mon, 02 Apr 2018 19:35:27 -0400, Gene Heskett > <[email protected]> > > wrote: > > I rigged the 5C to ER-40 to the mills table, then found I needed a > > draw bolt about 4" long to keep the R8 from rotating in the ER40 > > collet. So I saddled up and ran out to TSC, where I found the 7/16 > > bolts they had were only grade 5. So I got one and some washers to > > adjust the length with, came back and found the bolt was USS while > > the butt end of the R8 was SAE. So I'll have to round up some 1/2" > > A2 and put it all back in the lathe to apply a g76 and make some SAE > > threads. > > > > I also found I'll need a better way to clamp it to the table, > > probably by making a big v-block and a thick steel bar to clamp it > > into the V. > > > > Some days I swear its not worth gnawing thru the straps to get up > > and pee in the mornings. :( -- 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 [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
