On Monday 14 January 2019 21:53:54 Jon Elson wrote: > On 01/14/2019 04:37 PM, Gene Heskett wrote: > > Greeting Andy; > > > > The docs for G92 are a bit hazy, I find that with no arguments, it > > still puts the machines 0,0 at where the machine is ATM, which is > > not what I needed. Is this intentional? > > Hmmm, that should NOT change any offsets, unless it is a > special case of G92, with no axes selected. Otherwise, how > could you offset ONLY one axis, the others should not be > changed. > > Jon > Andy said I should see an error, and its possible that these alignment .ngc's are not being used correctly. No clue what LCNC does with a syntax error in a subroutine, which is how this stuff is run from the hal_mdi. They came with no dox not even a README. So the intuitive thing to do, is start at the anchor point, homeing to the 0,0 at the bottom left of the workpiece. record that. Then run up the edge to the far end of the piece and bring it back to touching the edge, and tap the align x or align y which then calculates the error angle and applies that. But those two button routines also contained a G92 x0 y0. And that jumps the home 0,0 to a foot away from where you started, It does apply the angle correction, but I've not tested that to determine if it corrects the error, or doubles it. So ATM I've taken them out as I don't believe aligning the machine to the workpiece should effect a change in the home position.
So until I'm cleared to actually do something so I can finish this frankenstein* build with my left arm, thats where I am with this. All I really want to do is make the rotation correction to align the machine to the workpiece without effecting the 0,0 position. If that needs changed to keep the work on the table, that's what we have touch offs for. This also needs a bunch of xml stuffs to hook it up and tally the sequences, and I got that hooked up yesterday. Any discovered errors are a matter of swapping + and - signs in the 2 subroutines, on designed to measure error along the X axis, the other along the Y. Mutually exclusive but a miss click on one is corrected by clicking the other. And of course there is a clear button to restore the default r0, which may not be, this particular code is rotated 90 degrees, more for testing this than for any machine limits reason, but that detected angle is a global variable the subs can access, so they apply the correction to the main.ngc's preset angle. IOW, it won't over-ride what you put in the actual carve it main routine, only trim it for miss-alignment with the bed T slots. Thats the general idea at least, and the other reason for a fixed 90 rotation. However once this align thing is working, that almost becomes a never mind. I like that. One of my next jobs for the lathe is to make a long contact probe like I've seen in some of this old tony's youtube videos. Need some drill rod about 3/32 diameter for raw material I haven't even ordered yet. Ticker sorta took precedence. *frankenstein in this case means I'm using higher voltage (14->28) for improved rapids along with the 2M542 drivers from the old HF mill. And in the final, lets make some swarf version, the only thing used in this things supplied driver box will be the vfd, which runs on wall power 127 volt AC. I might even graft that to a real heat sink and put it in a smaller box along with its fan. That shelf would lose about 20 pounds as that steel box must be 14 gauge steel. Thanks & take care, Jon. Cheers, Gene Heskett -- _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
