On Fri, 20 Jul 2012 20:00:10 -0400, you wrote: >Sag is only the start of the problem. The whip is going to be the real >problem. The ballnut is no holp holding it up at the limits of travel.
Not strictly true - the size needs to be CAREFULLY calculated for the job in hand and the mounting method needs to be considered. Good ballscrew manufacturers have tables that define limits for their screws, but the examples I've looked at require both ends to be fixed and max rotational speed of around 1000 rpm for a 3m long 25mm ballscrew with loads kept below 2000 Kg. As long as you follow manufacturers specs it isn't going to whip or destroy the ballnut. That said, for a 10ft long screw I'd go bigger than 25mm :) A Google search for ballscrew length versus diameter gives lots of data. www.techno-isel.com/Tic/H834/PDF/H834P011.pd gives some good info. Steve Blackmore -- ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
