Hi Ed, FWIW
Many, if not most, of the ballscrews on the machines I service are coupled to the motors by timing belts (various tooth types). I laser calibrate and do lead screw compensation adjustment on these machines and am amazed at how accurately they repeat. Different tooth types will provide varying levels of repeatability. See link: http://www.gates.com/brochure.cfm?brochure=7916&location_id=11536. Standard disclaimer: I have no commercial interest in Gates. Properly tensioned, a belt can be as rigid as a screw for the system it is driving especially when the belt length is reasonably short. On the machines I calibrate I tension the timing belt slightly more than contact to the pulley and get excellent results that perform well for my customers for long periods of time. I have never found it necessary to tighten timing belts like V belts but have often found them that tight from the manufacturer or from other technicians. Just sharing some real world experience without the conclusion that it is the answer for every situation. Have a good day, Jim ----- Original Message ----- From: "Ed" <[email protected]> To: "Enhanced Machine Controller (EMC)" <[email protected]> Sent: Monday, February 02, 2009 3:23 PM Subject: Re: [Emc-users] Hi All > Rainer Schmidt wrote: >>>Check out pico-systems.com >>>How are you measuring your backlash? Ed. >>> >> >> Thanks Ed. >> >> I use a regular magnetic base and a electronic dial indicator. Due to >> the use of the timing belts and no screws, there is no backlash. No >> hesitation whatsoever and all correlates with the intended pulses. >> R > > The problem with timing belts is that they and their support systems are > not as rigid as a screw. As an experiment set your indicator to the > spindle and gently push and pull (a few pounds) while watching the > indicator, a little deflection can make quite a difference in the > roundness of a hole. What kind of tolerances are you trying to maintain? > Ed. > > ------------------------------------------------------------------------------ > Create and Deploy Rich Internet Apps outside the browser with > Adobe(R)AIR(TM) > software. With Adobe AIR, Ajax developers can use existing skills and code > to > build responsive, highly engaging applications that combine the power of > local > resources and data with the reach of the web. Download the Adobe AIR SDK > and > Ajax docs to start building applications > today-http://p.sf.net/sfu/adobe-com > _______________________________________________ > Emc-users mailing list > [email protected] > https://lists.sourceforge.net/lists/listinfo/emc-users ------------------------------------------------------------------------------ Create and Deploy Rich Internet Apps outside the browser with Adobe(R)AIR(TM) software. With Adobe AIR, Ajax developers can use existing skills and code to build responsive, highly engaging applications that combine the power of local resources and data with the reach of the web. Download the Adobe AIR SDK and Ajax docs to start building applications today-http://p.sf.net/sfu/adobe-com _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
