http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/ CAD_CAM_EDM_DRO. Tue, 18 Jun 2013 14:07:03 GMT jcc3inc http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/message/99736 http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/message/99736 Hello, I've considered various means of providing movement and I prefer rack and pinion; the cost is relatively low, any length can be achieved, and as far as Tue, 18 Jun 2013 01:39:04 GMT AlienRelics http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/message/99735 http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/message/99735 ... Thank you, very informative. Steve Greenfield AE7HD Mon, 17 Jun 2013 22:41:38 GMT Ron Thompson http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/message/99734 http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/message/99734 ... Look into a Joe's 4x4 rack and pinion drive cnc router. Can be built to different sizes and cuts aluminum. There are enough you tube videos to get the Mon, 17 Jun 2013 21:21:36 GMT Steve Blackmore http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/message/99733 http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/message/99733 ... They don't stretch. See http://www.gates.com/facts/documents/Gf000284.pdf or http://www.sdp-si.com/D265/PDF/D265T003.pdf Steve Blackmore -- Mon, 17 Jun 2013 20:17:56 GMT Drew Rogge http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/message/99732 http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/message/99732 One way to get around whip is to spin the nut instead of the screw. The nut and motor are mounted to the moving carriage which I think would be the gantry in Mon, 17 Jun 2013 19:31:09 GMT Roland Jollivet http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/message/99731 http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/message/99731 If you have the belt teeth down, then what you could do is get another belt, and glue it to the table, teeth up. The belts now mesh together giving you a quasi Mon, 17 Jun 2013 19:14:52 GMT Jamie Cunningham http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/message/99730 http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/message/99730 Hey Steve - I've cut 80/20 with my chop saw - was scary at first but it cuts just fine - at first I clamped it into place and cut while cringing LOL but by the Mon, 17 Jun 2013 19:10:37 GMT AlienRelics http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/message/99729 http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/message/99729 ... Thanks! I think I'll revisit the idea of using timing belts. I don't need sub-micron accuracy, after all. The ShapeOko has a static belt with rollers Mon, 17 Jun 2013 17:39:42 GMT Tony Smith http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/message/99728 http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/message/99728 ... have ... take ... Belt drive works fine. Have a look at http://www.automatedwoodworks.com/Videos.htm, about 1:10 into the first video might interest you. Mon, 17 Jun 2013 17:18:14 GMT Tony Smith http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/message/99727 http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/message/99727 ... ...approximately 1000x1500x100mm (about 3ft by 5ft by 4 inches) Yup. Way too small for anything useful. Tony Mon, 17 Jun 2013 16:17:40 GMT cnc sales (hanermo) http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/message/99726 http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/message/99726 Not really. Acme is a std defined threadform, and you can get inserts for threading it from all manufacturers. So it the metric equivalent. The problems are Mon, 17 Jun 2013 16:01:34 GMT Art Eckstein http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/message/99725 http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/message/99725 Steve, To further reinforce what Andy has said, I have Derlin anti backlash nuts on my small router. I find that if I do much in the way of rapids at speeds Mon, 17 Jun 2013 15:57:30 GMT Roland Jollivet http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/message/99724 http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/message/99724 Drive the nut and not the rod. Keep the rod fixed in tension. The same can apply to a belt. Drive the cog and not the belt. So the belt will lay flat except Mon, 17 Jun 2013 15:45:12 GMT Jamie Cunningham http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/message/99723 http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/message/99723 My Acme screw is about 5 feet long and it whips if I go too fast - luckily for me at that speed my machine missed steps more often and so it's not the only Mon, 17 Jun 2013 15:44:50 GMT cnc sales (hanermo) http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/message/99722 http://groups.yahoo.com/group/CAD_CAM_EDM_DRO/message/99722 Unfortunately, you are off track. Your dimensions are WAY too small for anything except engraving. I do understand your needs re:costs, but .. Cutting