On 01.06.15 10:24, Gene Heskett wrote: > On Monday 01 June 2015 09:59:10 Erik Christiansen wrote: > > http://www.smbbearings.com/technical/bearing-shaft-housing-fit.html > > > Page is informative, but ends prematurely in iceweasel.
Goes right through to the "Contact US" and "Back to Top/Home" guff in iceweasel on my debian 7.8.0, so dunno what's bung there. (I had a rough idea you're running the same on at least one of your boxes - or were.) > The math looks like its all there, but I'd pay attention to the inner > fit so as not to crack the inner race at elevated temps since most > shaft material will expand faster than the ZR02. Yes, I'll be going to about 150°C, so that's the prime concern. The first cut at a shaft is in a piece of stainless steel from the junkbox. But if I can round up a bit of 440, then the TCs will match. I could measure the bit I have, then throw it in the oven, but the thermostat on a kitchen oven is pretty useless as a temperature guide, I figure. Hmmm ... a temperature probe for my multimeter? Might not do any harm to practice getting the clearance right for other materials, anyway. > While doing the breakin on the GO704, the quill got nicely above 125F > after 15 minutes at 1000 revs. To me thats a sign of inferior bearing > fit. I wonder if these might come in a size suitable for that? There are larger sizes and smaller out there. I think I'll skip the Silicon Nitride ones until I have a bit more experience, since they barely expand at all. I don't know what the risk is of the inner race creeping on the shaft if too much clearance has to be given to avoid cracking. I went for deep groove, since axial load is negligible, but I've seen angular contact as well, if that's what's needed. > But first I gotta get me/my back into workable functioning condition. > Unless they have some magic, I expect the screws & motor stuff will be > here before that. That should start arriving on June 9th. Backs are tricky. My mother has two artificial hip joints, and was dead keen to have the second, once the first proved a winner, but her bad back isn't susceptible to local magic - whereas my brother's came quite good after an op - fusing of two vertebrae, IIRC. Erik ------------------------------------------------------------------------------ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
