On Sunday 27 May 2018 23:54:57 Gene Heskett wrote: > On Sunday 27 May 2018 19:37:04 Gene Heskett wrote: > > On Sunday 27 May 2018 17:16:50 Gene Heskett wrote: > > > Giveing up on the jig brace, I decided to make a wooden one as it > > > doesn't have to last till the rapture. I laid out a circle, then > > > contemplated how to draw this circle such that its position was > > > offset half a mm for each time that it was drawn, until I got the > > > proper depth of cut. > > > > > > Without doing the arcgenm18 routine in 50 pieces of code, I tried > > > to make a sub routine out of it by manipulating the y offset, but > > > whilew it moved, it didn't want to do it in a straight line up the > > > y axis, but wandered off the the right and got smaller. I moved > > > vars around, but that failed similarly. So I got this wild hair to > > > move the co-ordinate, then I could re-use the same subroutine > > > until I'd hit the offset I wanted. But I stopped it as it was > > > starting the 2nd semi-circle, which means the y coordinate had > > > been moved what I thought was half a mm. > > > > > > But on further study of the docs, neither G10 L2 or G10 L20 take > > > anything but absolute values. > > > > > > So this means I have to get the current y coordinate from the > > > memory for P1's map, add my small var, and rewrite y with a G10 L2 > > > y new value. > > > > > > Except I moved it 40mm with the first command, and now it says the > > > first mpve will exceed the y limits. Then I noticed the - sign was > > > missing too for y. > > > > > > Is this a place where I have to g53 g0 x0 y0 z0 > > > and then rewrite the p1 map to all balls at that location? A > > > shutdown, restart and rehome has not fixed it. Then reset y for > > > each pass with G10 L2 P1 y[#5222 + 0.50000000] mm mode! > > > > > > And end the program with either a saved initial #5222, or another > > > g53 etc etc? > > > > And I just found out why the corrections applied are so gross as to > > disable lcnc. The value stored is in #5222(G54Y) is in inches, > > despite its being in G21 mode. So I need to divide my var for > > increments by 25.4 to make it inches. Sigh... Sure as hell there > > ought to be a way to walk a D pattern in a while loop without > > unrolling it to a 50kb file. > > > > Funny part is it looks great in the back plot. > > > > Thanks > > To those who wondered, its working and the poplar block is carved, and > while I haven't carved brass in it yet, its quite a bit more rigid. > I'm out of clamps so the tailstock is on a ladder step nearby, I bent > up a 6" piece of 1/8" alu panel that gently holds the slug into a r8 > driven by the table, so I think its going to work better than anything > else I've tried, lots better. I wound up sampling #5222 into a global > var and referencing that, the didling it to offset the tool a wee bit > for each pass thru the while loop, gradually digging the U channel > deeper. And restoring the Y offset by putting the global var back into > #5222 as it wraps up the job. typu correction above. > To Jon; I had to reset the pwm-servo several times, it was tripping > off at the m5, which is completely off while the motor was cranking > the spindle at 1500. So thinking about the motors emf, I put an s100, > g4p.5 in front of the m5. Hasn't tripped again. Its probably down to > 100 revs in .1 seconds, maybe less. As a 4 quadrant controller, when > its active, the motor responds _now_. I once measured the turnaround > time at about 400 milliseconds from 2800 to -2800, or back, > accompanied of course by a short chirp of the iron from the 16 amp > current limit I set in deference to the wire gage in the PSU > transformers. And that signal from motion has a limit3 in series with > it to slow that rail to rail signal down so the servo's current > limiter doesn't have to do it all. > > You make good stuff Jon. For anyone else similarly abusing Jon's > pwm-servo, by running a 1 HP spindle motor with it, from a 127 volt > psu, if its tripping the reset and turning on the led at a stop, put > an s100 in front of the m5, along with enough time delay for the motor > to be slowed. Should be the end of the problem.
-- 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> ------------------------------------------------------------------------------ Check out the vibrant tech community on one of the world's most engaging tech sites, Slashdot.org! http://sdm.link/slashdot _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
