Rainer Schmidt wrote: >> I believe that the proposed silicon sphere Avagadro/kg standard is >> 95mm +/- 30nm, which is a truly impressive bit of manufacturing. >> http://www.acpo.csiro.au/spheres.htm >> >> > > Owwwwwww I LOVE shiny stuff...... that sphere looks marvelous. I could > not take my hand of it all day 8). > > And yes, that is a marvel. > > Speaking of marvel.... To eliminate backlash and try something new at > the same time I am setting up my old bridgeport with a new belt I got. > It's a 2.5 timing belt with very fine teeth and it's 3 inches wide. If > that flexes I don't really wish to be around because the 'reason' of > that flex would be something to behold from a distance. To drive it I > will direct drive it with a servo and a backlash free cycloidal > gearbox which I found on that show in New York for an affordable > price. The ratio is 1:30 and the experiment will be done this summer. > If it works, it will be a great alternative to a ball screw with all > it's hidden issues. Right now I have very little to 0.125 backlash on > the X axis. Which makes a very messed up and dangerous operation. I > can only cut conventional in one direction or it will eat my > breakfast, bit, and material. Time to toss it or overhaul the screw > section... > R > > ------------------------------------------------------------------------------ > Crystal Reports - New Free Runtime and 30 Day Trial > Check out the new simplified licensing option that enables unlimited > royalty-free distribution of the report engine for externally facing > server and web deployment. > http://p.sf.net/sfu/businessobjects > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users > > That sphere and the accuracy is something. So here it comes :-) While working in a ball bearing research and development shop I found my self with nothing to do and was looking at the imperfections in a high grade ball under a microscope and was amazed a the craters in it. I picked up a diamond scriber and scratched my name on it. I showed it to some others who were amazed a couple of engineers looked at it and we talked about what your fingers could do if your eyes could fool them into thinking it was big. We did some experiments and what we decided was that fingers must be the most accurate thing on earth. It some point the writing gets pretty feeble looking but is still ledgeable. One of the engineers did a write up on this off the wall project for some engineering magazine. Every one in the plant from manager on down looked at the signatures on the ball and everyone was intrigued. The ball wound up in a mount on the president of the companies desks under a microscope I guess as a conversation piece. Doug
------------------------------------------------------------------------------ Crystal Reports - New Free Runtime and 30 Day Trial Check out the new simplified licensing option that enables unlimited royalty-free distribution of the report engine for externally facing server and web deployment. http://p.sf.net/sfu/businessobjects _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
