Hi folks; I took advantage of some near 60F weather and went out to the shop, bringing both computers up to date, then unplugged everything connected to the lathe so that C41 card wasn't hot, disconnected it and changed the analog output filter cap from the 10 uf that was in there, to a .22 mylar. That should thoeretically speed up the control by about 40x. Put it all back together and its totally different now, seeming dead stable but I have a bunch of slowdowns in spindle speed control path in the hal file, those are now extremely obvious. So, come even warmer weather to play in, I can now speed up the response times by at least 30x, making it considerably "stiffer" than it is now.
This means I can also speed up my electronic fuse, saving me a lot of bucks for fuses in the future. For a while last spring, I was spending 20 bucks a week for fuses at the Shack, about matching the outlay in carbide tooling. Basically, this post is for anyone using Arturo's cnc4pc c41 card to control a benchtop lathes spindle controller, change both of the 10 uf caps on it for something in the .1 to .22 uf range. Control will be very close to instant, effectively making the biggest low pass filter in the system out of the mass of the turning spindle and whatever chuck is mounted. Tuning of any servo is always easiest when there is only one major low pass pole to contend with. Cheers, Gene -- "There are four boxes to be used in defense of liberty: soap, ballot, jury, and ammo. Please use in that order." -Ed Howdershelt (Author) My web page: <http://coyoteden.dyndns-free.com:85/gene> is up! A man is like a rusty wheel on a rusty cart, He sings his song as he rattles along and then he falls apart. -- Richard Thompson ------------------------------------------------------------------------------ Keep yourself connected to Go Parallel: TUNE You got it built. Now make it sing. Tune shows you how. http://goparallel.sourceforge.net _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
