On 15.02.13 10:40, andy pugh wrote: > On 15 February 2013 10:08, Erik Christiansen <[email protected]> wrote: > > > The thing is that even a hefty little NEMA23 stepper can come with a > > radial thrust limit of 15 N, and an axial limit even lower. (I've just > > bought one from a local CNC goodies supplier.) There's no way the > > toothed belt pulley could be directly mounted on the motor shaft, and > > the belt then tensioned to the "twang level" recommended on this list, > > for acceptable backlash on the belt drive portion, is there? > > Recommended where?
Second post at: http://comments.gmane.org/gmane.linux.distributions.emc.user/29895 > I have a number of axes without even any tensioner on the belts (just > holes bored at the exact centres) and they seem to work OK. Even the > ones with tensioners are not "twang" tight. I might give it a go then. > There are belt designs with reduced backlash, and even zero backlash. > http://www.contitech.de/pages/produkte/antriebsriemen/antrieb-industrie/download/td_synchroflex_en.pdf > Page 23. > Suggested pre-tension is on page 26, and appears to be approx half of > the drive-tension. Thanks. That looks interesting. If I could go straight off the stepper shaft, it'd save a bit of work, and the couplings. But the tiny radial thrust rating on the stepper seems to kill that. Erik -- A man with one watch knows what time it is. A man with two watches is never quite sure. ------------------------------------------------------------------------------ Free Next-Gen Firewall Hardware Offer Buy your Sophos next-gen firewall before the end March 2013 and get the hardware for free! Learn more. http://p.sf.net/sfu/sophos-d2d-feb _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
