On Thursday 04 September 2014 22:04:46 Len Shelton did opine And Gene did reply: > We have a customer who is wanting to make a motor controlled rifling > machine. I spent a good bit of time researching it for him today and I > was surprised that it seems that no one is doing it with motors (or at > least I couldn't find anyone). I understand the need for the linear > relationship of the cutter to the position of the indexer in such a > machine. But I wanted to hear your guys thoughts on doing this with > motors, which will inherently have some degree of granular positioning. > > Here is the best machine design I could find that really demonstrates > the issue: > https://www.youtube.com/watch?v=L_yemjfgkE0 > > >Len
I don't see a thing there that cannot be done with steppers, nema 23's driving the big pulley thru timing belts, with the rotation being a variation of the G33.1 function. But I'd not use the pulley & crank at all, but just a bigger stepper and ball screw because then you would not need the math to translate the rotary motion into the linear position to drive the G33.1 inputs. The biggest problem would be in adjusting the number of grooves in software, but I don't believe that its a problem hal or gcode cannot solve by running a start point cycle back and forth with a mod function in the gcode math. Interesting problem, but one that I believe lcnc can do with creative coding. But is cut rifling enough more accurate than the other two methods, both of which are at least 100x faster, to make it worthwhile to do it that way? Thats the $64K question. IMO yes. :-) I wish I knew I had 10 years left, I'd be getting started on just such a machine. Just for S&G. And bug hole sized 10 shot groups of coarse. Cheers, Gene Heskett -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) Genes Web page <http://geneslinuxbox.net:6309/gene> US V Castleman, SCOTUS, Mar 2014 is grounds for Impeaching SCOTUS ------------------------------------------------------------------------------ Slashdot TV. Video for Nerds. Stuff that matters. http://tv.slashdot.org/ _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
