OK so Im new to this, I have openbuilds blackbox connected to a typical aluminium extrusion built CNC router. I've been happily routing out pieces for my projects and the world is good . So yesterday I was rattling off a few more pieces, the blackbox wanted to update the firmware, I manage to postpone it a few times and made a few pieces, I think the firmware managed to update itself without me noticing??? Next thing I ran the job and it buried the spindle right into the spoil board, wrecked my job and scared the life out of me. So before I ran it again, I offset the zero point well above the bed, ran another job ( a job I've succesfully made a number of times) and sure enough it moves to -13.5 in Z then travels to the start of the job . Once the machine gets to the start of the job, the spindle then retracts to the correct height and would complete the job as programmed. I can repeat this everytime. I've looked through the settings and can't see whats wrong. My first thought was the firmware update must have lost some GRBL settings but everything looks OK. Any Ideas?
1) Firmware updates are not automated 2) I think you refer to CONTROL wanting to update it self 3) It will never do it itself, only once you click on Continue (It will keep asking every hour though) Almost impossible to be updated related, probably more a case of forgetting to set Zero? Most importantly CONTROL does nothing to change the sequence of moves, it takes your GCODE file, and sends it unchanged to Grbl, line, by line. So if does funny things, check your CAM side, as the moves all come from your Gcode
OK well I can't figure out why the machine wants to ALWAYS now travel to the start of the job at -13.5 and then retract to the correct height and proceed. I always zero the machine with the openbuilds probe. Im at a total loss here. Im not doing anything differently to how I've made all the other parts. Where should I look? Fusion 360 doesn't simulate this move plus I've tested a Gcode that I've not changed and previously made successfully.
Then that'll be Fusion's G53 (machine coordinate) move. That moves to where you HOMED the machine. If you don't have limit switches, how is kind of an unknown, and then you can "fake the home" but its better to just install switches and setup homing, so Machine coordinates are always repeatable and predicatable
OK is there a work around until I get the switches installed? I Just need to get some cable before I can install them.
Thanks guys. faking the home seems to have resolved my current issue. I will get the limit switches installed before running any more jobs I think. Can you advise me what the best practice approach is for installing the limit switches? X,Y,Z positive or negative position. Any ideas what I pressed to cause the issue of losing the home position???
Grbl resets home every time you abort, reset, power off, etc. As it well should - any of those actions makes it loose position in the physical world, so rehoming is appropriate. Z Positive. XY Positive is default, but doesn't matter as much as Z does. See gnea/grbl and also see Trouble Shooting Open Controller
