On Saturday 28 November 2015 13:27:45 Gene Heskett wrote: > Greetings; > > I have a bunch of named #<_vars> that control this button carver code, > mainly so I don't have to reinvent a wheel in different files > everytime I change a measurement by 2 thou. > Update; Contrary to the book I googled and read, which describes TLO for both LCNC and Mach3, in LCNC at least a negative number in the tool table's z entry IS legal, and it appears to be working although I've not yet made any black dust with it. Thats next. I have about enough scrap I can finish the 48 baseboard sized buttons I need.
The docs, in our own .pdf, need a better treatment of the tool table contents in the G43 discussion, its pretty thin, malnourished even. Maybe this might help another new bee? > Trying to get the G43 and G49 commands to behave and failing > miserably. > > I followed this procedure to calibrate things, > 1. Rig a contact plate on the table, some 3/16" below the workpiece > top Hook a clip lead to the probe line to this contact plate. > 2. F5 MDI "G49" > mount a 1/4" mill, with about the longest stickout in my kit > 3. f3, run it down to probe stop at .7 ipm final velocity > 4. touch it off at 0.0000 > 5. raise, change to 1/8" mill, > 6. run down to find contact, > 7. enter z dro in tool table as a positive value in that tools Z > column. 8. raise, change to 1/16" mill. > 9. run to find contact. > 10. enter Z dro as positive Z value in that tools tool table entry. > 11. put 1/4" tool back in spindle > 12. run it down to a gentle grip on a 0.005 feeler blade > 13. touch off to 0.005 > 14. edit gcode to enable use of tool 14, the roundover tool. > > The gcode for G43/G49 looks like this: > (==================main loop=====================) > G49 ( cancel any tlo in effect ) > ( load new tool ) > o<ifrndover2> IF[#<_rndover> gt 0.500000000] > M6T14 > o<ifrndover2> ELSE > M6T11 ( 11 is the 1/16" mill ) > o<ifrndover2> ENDIF > ( apply tlo of loaded tool ) > G43 ( use tlo "Z" from tool table ) > ( my subroutine runs in a G92 x0 y0 z0 environment because its a step > and repeat driven from the main loop, may get used up to 10x a run, so > ) G92.2 (in case I've stopped it and am restarting and the sub's > environment is in effect ) > > 15. Run the code, it shaves perhaps .001" off the original run that it > had already done once. Tolerance in how I feel the tool gripping the > feeler blade I expect, no biggie. > > 16. Edit gcode to turn off roundover bit (0.00000000) and use t11 by > default. > 17. reload code into LCNC. > 18. run code, see snippet above, very very slowly because the first > time it went 1/4" too deep & snapped off my next to last 1/16" mill. > 19. The status screen shows the correct nominally .5043 tlo applied > 20. As it approaches the point of where it should start cutting, its > nominally 1/2" up in the air and stopped, waiting for advice. > > Relevant tool.tbl entries: > T1 P1 X0 Y0 Z0 D0.246 ;1/4 inch mill, small for glue line > T11 P11 X0 Y0 Z0.5043 D0.0625 ;a .0625 2 fl end mill > T14 P14 X0 Y0 Z0.6095 D0.025 ;roundover bit > > Any insight as to where I'm screwing up will be appreciated. > > I'm thinking of adding a G53 g0 x0 y0 z0 at the top of my code, but > thats a nearly 1 minute operation by the time it runs back to the > working point. > > Is that what I need to cancel any and all previous offsets? > > I just went back and repeated it, twice and everytime I do, the 1/16" > mill winds up about 1/2" higher. > > Using all G92.2's now because I don't want to lose my starting x/y > offsets in the main loop. > > Thanks all; > > Cheers, Gene Heskett 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> ------------------------------------------------------------------------------ _______________________________________________ Emc-developers mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-developers
