On Sat, 21 Jul 2012 14:41:01 +0300, you wrote: >2012/7/21 Erik Christiansen <[email protected]>: >> >> In any event, I'd fix a long slender ballscrew, to avoid whipping, and >> rotate the nut. > >I did this on the last machine I built with this exact intention in my mind. >The overall result - failure. I seriously doubt I will ever do that again. >Longest screw was 2800 mm long (other 2 were 1800 mm long), all of >them - 16 mm diameter, 10 mm pitch.
Yea - too small a diameter screw for decent performance at that length. I have a 2.5m ballscrew here that came off a laser cutter. Now bear in mind there are no cutting forces involved, it was off the Y axis and only moving the head across the gantry. It's 32mm diameter and has large bearing blocks and preload adjustment on both ends. Also has two ball nuts for backlash adjustment :) I also have another 32mm one that was an unused spare off a Denford CNC lathe - it's only got about 300 mm of travel but was designed to be fixed at one end only - hence the diameter. They were destined for a slant bed lathe I designed but I never got around to building it <G>. 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 [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
