You might have an unsupported "tool change" command in your G-code. There is a brief discussion here: UGS G-Code Operation

Grbl does not support the M6 command. If you have a line "T1 M6" in your code, you can safely remove it.

Edit: BTW, I believe if you just "OK" at the error, the rest of the code will execute (I think grbl handles it that way just in case you really do need to do a tool change - temporarily halting.)

 

gnea/grbl

 

Thanks, Scotty and Craig. Yeah, it was an "M6" command, I did click through it and it continued to run.
So, now I have connected all the motors and I have a "working" CNC (hooray!). I am just doing some testing by jogging the machine through all of the axes and have found a new problem; the "Y" motors are running at different rates so the Gantry is getting skewed as it travels. I notice the left "Y" motor actually skips while the right motor continues. Because of this the screws are being pushed out of the front of the machine and the flexible coupling is expanding on one side or the other. I also noticed that while idle I can easily turn one of the motors but the other won't turn, but when I disconnect the power the "stuck" motor then turns easily. Any thoughts or solutions?

 

You shouldn't be able to turn a motor when powered up and idle. I think check your wiring connections on the "free" motor (maybe test it alone). When energized, it should not turn by hand.

It's probably skewing because the working motor is dragging the free motor along.

 

Or your wheels or delrin blocks are too tight

 

It's been a few days but I've cleaned up the problems with the motors running out of sync. I checked and adjusted the wheels (thanks, Craig), and check all my wiring (thanks, Scotty). I've been doing some jog testing and we are good! But now I have a new problem; I loaded a test toolpath (using Universal G-Code sender) and the CNC is making a very tiny version of what I've designed (I'm just running the machine without a router for test purposes). What have I set incorrectly (or not set) to make this happen? I've done some searches via the Universal G-Code Sender site but can't seem to find anyone else with this problem/solution.

 

It looks like the toolpath is set to inches and UGS is set to millimeters. Scale the toolpath up 25.4.

 

I don't know how to scale the toolpath

 

What program did you use to create toolpaths?

 

Fusion 360

 

Yes

 

That fixed it! Thank you, Mark.

 

Mark, where can I learn more about GRBL and why this worked?

 

I have installed Limit Switches to all Axes and wired to xPro Controller. I saw on a previous post the GRBL line command to program the switches with a .5" back-off but now I can't seem to find that post. Can you help me with what the GRBL instruction is?

 

Hi Gang,

As much as I hate yelling for help, this is one of those times. I've completed the entire build and have enjoyed the entire process, but I'm now in a whole and can't get any further without a bit of help. I have no movement of any stepper motor. I have installed UGS, all wires have been traced over and over. Voltages have been checked and I'm about to hang up the xpro and install a BOB and Mach 3.

Thanks, Larry

 

With the Limit Switches wired up and GRBL code $22=1. I send command $H for Homing and Z Axis moves up to contact the Limit Switch and it results in Error 8. According to instructions I've been reading it is supposed to touch each Limit Switch, execute the "Back Off" and re-touch the Limit Switch throughout all Axes, but that's not what's happening. After each event like this the machine needs to be powered off, manually clear the Limit Switch and then $X resets UGS. Where am I going wrong?

 

Hi Mark,

I want to thank you in advance for the extra work you are giving this project and all the assistance given to us non-programmers.it's a little tough here in the woods sometimes. So far I have tried GRBL panel without success and UGS does nothing at all.Tonight I plan to trace everything from the power source to the steppers looking for any sign of life.

I actually believe that the problem is in the firmware. If I can get a clean working copy of the firmware and can eliminate that option I believe that I'll be far ahead of where I am now. (i hope).

 

There are far more than one reason I enjoy shopping at Openbuilds Parts Store!

Thanks for the help.

 

Very nice. Much appreciated. Thank you Mark.

 

So here's my latest problem: the CNC is not cutting according to my designs. The attached photos and pictures show what the planned part is supposed to look like and what the resulting cut parts are coming out as. Straight lines are not straight, radiused corners (.0625 radius) are way to big and lopsided where they should be symmetrical, the hole is cut oval. Is it my speeds and feeds or is it an erroneous toolpath? My toolpath is generated from Fusion360 using GRBL/grbl configuration driver. Using the DeWalt DWP 611 at 27000 rpm, my feedrate is 62.5 in/min with a .125 Dia router bit.