Hi all, Blackbox user here. After homing my machine with no problems, I the start to run the job only for the Z axis to limit out straight away. I have tried adjusting the settings all to no avail. This issue has just started following me having the replace a broken drive coupling on the X axis. Any help would be most greatfull.
what software? if Fusion360 with the OB postprocessor, then set the Z holdoff distance to -5 or -10 if -5 is not enough. This is always entered in MM but the Gcode output will uses inches correctly if inch output is desired.
Hi Peter, I am not using fusion! I beleive the problem lies with one of the $$ settings. The machine homes without any issue whatsoever, it touches the limit switches and retracts but as soon as I begin to run a project the Z axis raises up and hits the limit switch. I have increased the pull off up to 10mm but this has made no diferance, the machine comes to a gringing halt. Thanks, John.
Sorry, please, then do tell us what? You haven't confirmed on denied - so I continued with the assumption, sorry! Indicating the GCODE is causing that, so, please do post the GCODE file, screenshots of your CAM setup, etc and let us know what CAM you are using (Can only make guesses and assumptions in the absense of information) Have a read through what pull-off actually does Grbl v1.1 Configuration · gnea/grbl Wiki - just clears the switch. Home point is where the switch TRIGGERED, not where it ended up after clearing the switch. Thus all G53Z moves should be <0 (never 0, or more - thats past the trigger point and thus hitting the switch), G53 Z-5 for example would not hit. G53 Z0 and G53Z5 would hit the switch Of course, still assuming G53 moves even exist, in the absense of the CAM info and GCODE file You are remembering to Zero the axis right? Lastly, is your Z axis calibration correct? (Perhaps its moving further that Grbl things it is, because your steps per mm is incorrect?) Any changes you made recently? Even if it seems unrelated, do mention
Hi Peter, Thank you so much for helping me, I have attached as requested. I hope these are of some use. John
OK, so you are using OpenBuilds CAM We do not use homing/machine coordinates/etc - only more advanced CAMs do that So, for OpenBuilds CAM to crash the Z, you have either one of the following mistakes - Too thick a combination of stock + the value of Z Safe/clearance height entered into toolpaths - for example, if your Z axis only has 50mm of travel, you put down a piece of 40mm stock, and tell OpenBuildsCAM to use a 10mm clearance height = crash - screenshot your Toolpath parameters and tell us more about the job involved to check this for you - Forgetting to ZERO - as all moves are relative to where you zero, incorrectly - or forgetting to - ZERO the machine before running the job can lead to crashes - Z Axis not calibrated (See CONTROL > Wizards and tools > Calibrate menu)
Thanks for the advice Peter, I will shech this out in the morning as time is getting on here in the UK. I will let you know how I get on.. Thanks once again, John.
Hi Peter, I am please to say, I have resolved the problem with your help. Quite simply it was all down to me not completly understanding the positioning of the workpiece on the machine in relation to how it is on the software and a having a faulty micro switch!!!!! Where would we be without people like you. Many thanks again. John.
