Originally shared by Anool Mahidharia
I suggest my pcb2gcode postprocessor to do the z probing automatically and in a 10x10 grid. (unless you found the perfect way to mount a PCB without it flexing l.
Your cutting depth and thus results for small traces and tool life should increase dramatically (and it’s less manual work in preparing each board).
I’ll give it a shot and see how it works for me. I usually stick the board to my Bed using double sided tape. It would help if I can manage to do thinner tracks.
This program is for MACH3.
For EMC2 a script doing the same is linked in the blog posting.
oh, Pity. I use neither. Running a GRBL on a GRBLShield
Can you tell me the command it uses for a straight probe and what variables are available?
Then I can add support for that too.
okay. I’m just about getting my feet wet in G-Code. So, it’ll take me a while to figure that out. Will reply back here once I know.
Yah I made a “Z probe” for tinyG. Its not really a probe. Its a homing switch set to normally open. So i attach an alligator clip to the endmill then I attach that line to the input for the limit switch on the Zaxis and then issue a home on tinyg. G28.2z0 (Note that is how you do this in TinyG)
Also I have learned that when mounting PCB’s you should get a solid piece of wood or something under it. I have a very nice piece of oak wood that I clamp down. Then I drill the pcb on the outter edges to the wood. Its perfectly flat now. Works for me. I will post a video of how I do it. My wife’s b-day is today so I am not sure I will get to it today.
I have a TinyG I can get you at the summit. This will get you better movement and lots of other features that you are missing.
You should not do a single z-probe but a grid.
What I did was modify the G-Code to do a 10x10 grid, store these in registers, replace all Z-coordinates with bilinear interpolations, replace all long movements with shorter movements that have their own z-coordinates.
If your piece is perfectly flat then a single probe should work. But I see the utility. Nothing is perfect. You said you did this in Java? Is your code available? I would like to take a look.
If you mount your PCB with a vice, it won’t stay flat but bend ever so slightly.
Hardly anyone has a vacuum table.