On Friday 16 February 2018 06:16:00 Chris Albertson wrote: > If you are bending a screw the speed does not matter it is the > acceleration. That is measured in meters per second squared (or > whatever the Imperial equivalent is? feet per second per second?) > > I think a typical low performance mill like most of us have might have > go a 2m/s^2 A very high performance one might do 20m/s^2 > > If the mill can do about 10m/S^2 then the force on the ball screw is > equal to the weight of the table and whatever is bolted down to it. > Remember what Newton said "f=ma". > > Which happens first the ball nut breaks or the screw bends is > determined by the length of the screw from motor to nut. > > Gene when you used the motor in a design where there was a very large > static load, where the motor had to hold the weight of large vertical > moving head you'd expect poor movement compared to a horizontal axis.
That I have figured out finally Chris, its moving close to 100 ipm with a 32 to 42 pulley set in the z on my Sheldon but its noisy as can be in the 7 to 20 ipm box. Its noise telegraphs up the keyboard shelf mounted on its mounting bracket. I'd had to put a 1/4" high fence around the edge to keep other stuff from vibrating off including the keyboard itself. Its also running an a few more volts than it was on the mill with its heavy head. 7 more volts IIRC. X is slow, but if I ever get off my duff and make a thin vibration damper, I think that would bring it up to 60 ipm. Its a nema 24, 8 wire, wired parallel and getting all a 2m542 can give it at around 43 volts. Neither motor is best match, but what I had, or could get in the crowded area behind the new apron. > On Fri, Feb 16, 2018 at 12:54 AM, Gene Heskett <[email protected]> wrote: > > On Friday 16 February 2018 02:20:40 jeremy youngs wrote: > > > Chris, I think you are spot on . Nema 34 1600 oz in. And > > > automation direct 110v drives. > > > > I have one of those motors. On the Z of my mill, with a 60 volt psu, > > very poor performance. 27 ipm or stall lifting the head on the > > G0704. Its now on the sheldons Z and while noisy, is also about 4x > > faster. > > > > > I had y at 300 ipm 9×42 table. It was a very cheap > > > ballscrew and I had it cobbled together now that the Machine is 3 > > > axis and spindle functional I will be able to make some belt and > > > pulley mounts and resolve some issues. > > > ------------------------------------------------------------------ > > >---- -------- 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 > > > > -- > > 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 -- 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
