Hi guys, CNC newbie here. Ok so I’m only roughly setting my work zero at this point because it’s my first cut and I just want to get a feel for it. $132 is set to 26mm, this will reach the spoiler board. I move the router into position to set my work zero, the stock is 18mm and I lower the router 8mm. This actually leave the router bit a fraction above the material but like I said I’m not too fussed about that right now. The machine returns back to the machine zero and then moves to the start point it cuts into the material as you would see it in Fusion. But before it lowers to the material it retracts again making an awful sound where it’s run out of travel upwards and then plunges into the material. My cut depth is set to 2mm per layer in Fusion, but it’s actually cut depth is approximately 10.6mm. I’m just confused to why it retracts the second time. It’s clear that the machine thinks it’s 8mm higher than it but I don’t know why. I thought it could just be a wrong value to do with homing but I'm not sure. I don't have limit switches currently although they might be helpful. Here are my values. I hope I got the terms right, any pearls of wisdom are welcome. Thanks in advance =) $0=10 (step pulse, usec) $1=255 (step idle delay, msec) $2=0 (step port invert mask:00000000) $3=6 (dir port invert mask:00000110) $4=1 (step enable invert, bool) $5=0 (limit pins invert, bool) $6=0 (probe pin invert, bool) $10=3 (status report mask:00000011) $11=0.010 (junction deviation, mm) $12=0.002 (arc tolerance, mm) $13=0 (report inches, bool) $20=0 (soft limits, bool) $21=0 (hard limits, bool) $22=0 (homing cycle, bool) $23=1 (homing dir invert mask:00000001) $24=25.000 (homing feed, mm/min) $25=500.000 (homing seek, mm/min) $26=250 (homing debounce, msec) $27=1.000 (homing pull-off, mm) $100=26.667 (x, step/mm) $101=26.667 (y, step/mm) $102=200.000 (z, step/mm) $110=2500.000 (x max rate, mm/min) $111=2500.000 (y max rate, mm/min) $112=2500.000 (z max rate, mm/min) $120=50.000 (x accel, mm/sec^2) $121=50.000 (y accel, mm/sec^2) $122=25.000 (z accel, mm/sec^2) $130=820.000 (x max travel, mm) $131=1275.000 (y max travel, mm) $132=26.000 (z max travel, mm)
Hi Gary, is this what you mean, the .nc? I've added the Fusion file just in case. I was getting an issue with tool changing T1 M6, but I read online that you can just delete that line. Correction: the cutting depth of each layer was 3mm.
In Fusion you have set a clearance height of 10mm from the retract height of 5 mm (from stock top) so the g-code has a total height above the stock of 15 mm, but the stock is 18 mm and you have set Z max travel at 26 mm. You need to reduce the clearance height and/or the retract height so that it all fits into the 26 mm you have set for Z max. Out of curiosity what machine/controller is this and what post processor did you use in Fusion? Alex.
Ha. That makes sense! You know what I don't even remember changing those heights. I must have just gone into that tab, messed around with it and forgot or not thought much of it. Thank you very much Alex, I'll have a look at those height and is if I can get it right again. The machine is an OX, the post processor is set to Grbl and UGS.
Use these settings for the fusion GRBL post. f360/ob control Or use the OB post Fusion 360: grbl post processor install (the easy way)
Hi David, thanks for the reply. I'm going to head to the garage today to give it a second go today so I'll have a look into it. I'm guessing this is better than the built-in post processor? To put it simply.
No matter which post you use, you still need to understand the settings (read the popups as you hover over each setting) and set the heights in Fusion correctly. Also, Fusion, and all other gcode generators, makes some assumptions about the machine setup so for it all to work together there are things you need to do, like Fake the Home if you don't have home switches and homing enabled.
I do have a lot to learn and I did some research into G and M commands to try and gain some understanding of them but they didn't really mean much to me without any experience on machine. I will give the resource section a going over. I ran the cut albeit with a clearance height warning, wasn't sure what it'd do, so I did it anyway and now I know. The second contour and the pocket cut deeper because of the height clearance issue. The circle wasn't quite a circle so I'll need to tune my values from the baseline but all-in-all it's a step in the right direction and I'm pretty happy. =)
