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 #5522 as it wraps up the job. 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
