Funny, this. I’m working on another machine right now with one x and 2 y, same problem. Grbl mega 5x from the github, not this port. I’ve already tested my switches, the pins on the board, the config and the map, and run new wires. I’ll let you know if I figure out MY problem.
@tony and @joloco59 maybe you are working with a wrong grbl version. You can work with my grbl version (you have the link above this post).
@joloco59 if you already are working with it and you only have homing problems I think you can fix it changing the homing mask direction. Each axis has a bit, now you have $23=31 (11111) so you have all axis inverted, try with (11101)=29.
Yeah. I pulled the latest fra589 repo because it was so recent and I only have 4 axes to deal with so I need to edit the config anyway. But I just noticed last night it doesn’t seem to have autosquaring (at least not the way I’m expecting to find it, as you have implemented).
The default config and cpu map in mega 5x looks like it’s mega/ramps, so I’m not even sure why to use one or the other, honestly.
Do you have any idea what all the differences are between your version and the new one? I don’t expect you’d have time to keep up, but can’t hurt to ask.
I think I got my problem narrowed down to either a sloppy switch or noise, but the wire is routed away from everything. Sometimes Y1 works depending on how much wire I unplug (3 seperate stretches of wire get plugged together so I can hide things in the frame and easily disassemble when I move in a few months). I don’t think that really sounds like a firmware problem, right?
Either way, I want the autosquaring and I’m certain your version is on my primo, which works flawlessly, so I’ll try that. Thanks again for putting this together.
I managed to find my error, it was my limit switcher that were triggering on Y axis, added some 0.47 uf caps to the board problem resolved. all working perfectly.
are there PWM pins available, other that the laser and spindle pins?
I would like to connect a servo to deploy as a probe for the Z axis.?
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This was indeed my problem added some smd caps to limit pins on ramps board, problem gone now.
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Yup, noise for. My capacitors showed up and I jammed them in the plugs, problem disappeared. Some NC switches also showed up so I may as well swap them in, too. Both types are button, not like we use on the mpcnc, so maybe it’s them and not the wire since this isn’t an issue on my mpcnc.
Hello everybody.
I do not understand what “auto squaring” consists of, sorry for my ignorance.
An mpcnc uses 2 motors for x, and 2 motors for y. As such, when you turn it on the motors will likely be positioned so the x and y are not square to the table. Without ‘auto square’ you will have to manually jog the 4 motors to get the x and y squared before each use. With autosquare, you have 4 switches that are used to square the x and y before cutting. Basically you adjust the position of the 4 switches until the axis are perfectly square after homing. Once those switches are positioned properly, you no longer have to check square on the gantry before each use… just home the machine and it ends up square.
If you are familiar with 3D printers… this is similar to using dual z stops and dual z drivers… it allows you to auto level the x gantry before each print. Same thing here, but we use it on the x and y instead.
Btw, that quoted comment is not accurate… grbl does support autosquare for ramps and other boards. Perhaps that comment was made when working examples were less commonly found, but it has always just been a matter of proper firmware config a to get autosquare working with grbl1.1.
Kev is your comment for my question?
autosquare is the homing?
Yes it was… but I was a bit unclear. ‘Auto square’ is a feature you can add to an MPCNC, which requires 4 limit switches on your X and Y gantries (one for each motor). When autosquare is enabled in firmware, it becomes part of machine’s homing routine. You would notice while homing it hits the switches, pulls back, and then moves one motor at a time. A total of 3 bumps per axis, and when it’s done homing the gantry will be all squared up and ready to cut.
Without autosquare, the firmware will never automatically moves a single X or Y motor on it’s own like that; You have to manually tell it to with gcode. So when homing an mpcnc without autosquare, you get 1, maybe 2 bumps per axis, and X1 will always be in sync with X2 (same with Y1/Y2). Of course that means if it’s out of square already, it will stay out of square after homing. You will have to use gcode (or a nice GUI… same diff) to jog X1 independent of X2, and same for Y1/Y2 to manually square the gantry. Whether you use stop blocks, a T-square, or whatever method to measure, that’s a lot more work than autosquare… and required every time it gets powered on before cutting.
Manual squaring is a hassle and adds a lot room for error. The cost of eliminating it is just adding 2 more limit switches and configuring firmware. If a board did not support autosquare, I would say avoid it for mpcnc use.
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Hay algun enlace o video donde pueda yo ver como funciona una MPCNC?
I responded to your other thread. But there is also more information on the dual endstops here:
Hi guys, I’ve been running an MPCNC as a drilling machine running this version of GRBL. Up to now its been great, homing etc… all works. I’m now trying to do a bit of milling and i cannot get it to cut arcs, it behaves really strange, as soon as it sets off on an arc it runs off coordinates far away from the arc. For instance G2 X86.75 Z-1 I0.25 K0 will send the machine off to x-150 or so and the machine just stutters all over the place and crashes. Any ideas what on earth is going on?
Hi Gareth Malham, I’m reading this now and it’s been a while but I was wondering if you’ve resolved it as I have a similar problem, were you using UGS?
Hey Julian, this thread is nearly three years old, rather open a new one and describe your problem in a little more detail. 
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Hi Felipe, yes, I didn’t want to bother with a new thread since I was using this version of grbl from Pablo Casaña and I had a problem with the rotation of the cloned A axis and B axis, but I’m going to open a new thread as you say. Thanks.
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