Ask Grbl CNC questions here.

Openbuilds control? bCNC?

 

This means my USB cord is probably scuffed up, right? The job stops with no error and I'm able to press "pause" and then "unpause" to get it going again but after the third time, this error came up. It's done this in the past and I thought it could be EMI so I've been getting it more humid than usual and putting anti-static spray in the air but it's been happening again even with these measures taken.

So, USB cable?

EDIT: USB suspend has been off forever, so it isn't that.

 

I’m not sure about the error, but my machine was giving me the same issue where the job would stop randomly and I could pause and resume it and it would start back most of the time(sometimes it wouldn’t) I was advised by @Peter Van Der Walt:

Random pausing is more likely PC side: Windows updates re-enabled USB Suspend maybe? docs:blackbox:install-windows-selective-suspend [OpenBuilds Documentation] or replaced the FTDI driver with some Microsoft generic? docs:blackbox:install-drivers [OpenBuilds Documentation]
Correct version of CONTROL? OpenBuilds Software - FREE Software for CNC Control: OpenBuilds CONTROL and OpenBuilds CAM(v1.0.317 at the time of this reply)

Could still be EMI though - see docs:blackbox:faq-emi [OpenBuilds Documentation] (Serial corruption perhaps)

I think mine was the pc side issue. I had emi issues as well, but I don’t think it was causing the random pausing that you are talking about, but it still could possibly be emi.

good luck!

 

This is fantastic information, thank you so much.

 

Well here we go again. I turned on my 1515 about 10 minutes ago and hit home. Would not run test. Gave a fault code of "Numeric value format is not valid or missing an expected value. [ $J=G91 G21 Y-1000 FNaN ]". Any help would be great.

 

I reset the op systems settings and it fixed it. Thank you for you quick response.

 

Could you point me to a resource to better understand the source code, I have a custom machine and Really need a pause command similar to M0 but where spindle/laser/plasma arc does not stop. Was thinking of using M1 on my machine even tho I know it couldnt be implemented in the mainstream...... I have searched and read and tried various options to no satisfaction.... Please any direction/ resolution would be appreciated.PS.(I know M1 has a usual function that is currently un supported) thx

 

What exactly are you trying to do? You are trying to pause the movement of the steppers with your laser/spindle/plasma still on and enabled?

There is a grbl wiki page that explains all the commands, but I’m guessing you’ve seen it?

here it is:
Pages · grbl/grbl Wiki
Good luck!

 

Ive read thru commands(g and m), as well as source code. What Im looking to do is edit possibly M1 to do a stop but allow (laser/spindle/plasm) to remain firing. Possible with a time limit. Ex M1 P800. Movement stop, keep firing for 800ms

 

Does Feed Hold not do what you want?

 

If my understanding is correct In code m1 technically not implimented, it coded as m1 == m0, and m0 linked to feed hold, which pauses everything including shutting off laser/torch/spindle..... For my machine I need torch to stay on while movements pause and wait for an OK signal from Torch hieght control.... tried dwell and its ok, but there are precision issues using a dwell/delay. The idea is to send a torch lite command(m3), then (m1/m0) but not shut off torch.... the when Thc recieves signal from black box(m3 command) it goes thru a proccedure that takes an undetermined amount of time and when done sends back an ok to preceed signal.(resume)
I know most will frown on it, but because m1 is not implemented, I would like to change or have changed source code so that m1 is a mivement stop only with a keep torch for a settable amount of time...... for ex m1 p800. Mechanical hold 800ms

 

Try asserting the F/H input. That pauses motion but leaves spindle on. You might be able to output a F/H signal from your THC and then, when it stabilizes, output a cycle start signal. Might be easier than changing the GRBL code.

You might want to look at GrblHAL, a 32 bit version of Grbl. There is some work done on a THC plugin for plasma.

 

Ill give it a shot...... i know thc does not have a feed hold output..... and all my investigations say feed hold stops spindle too...... but ill try it for myself. Thanks all

 

Nope, F/H keeps the spindle running. I wish it didn't.

 

Ok so here is where I'm at .... I have a SF-HC25G/25K Torch Height Controller... and to be honest documentation is horrible.... If I can get this sorted out I will prob write my own and share. It seems to work well, however the caveats that I have run into it how to integrate into grbl/black box. issues an attempted solution. It replaced z motion. When Grbl/BB sends out an M3 (so BB relay GNDS (per my wiring), it activates THC, which does a touch off to a set height, then fires plasma and changes height to maintain proper arc voltage (per my setting). sends a resume signal back to grbl/BB and expects a return "Auto signal".... This is all within milliseconds. I have in effect done 2 things, switched pins A1 and A2 in source code so that the black box now sees resume on what door switch (this works) was. I designed a circuit that "ANDS" the fire signal from Grbl/BB, and the "OK" signal from THC to create an artificial "Auto" signal (This works). What is not work as of this moment is the timing. For example, if I have a gcode file to cut a simple 2"square, and in gcode insert an M0 directly after M3, so it should fire and wait for resume, then it should continue, however it seems like the buffer empties (I'm guessing), and therefore there is nothing to continue with........ Also, the THC is all 24v except the interface to grbl/bb it can be 24 or less.... currently i am using the servo 5v line to power the interface, however I'm not 100% the amperage requirements are causing issues (buck converter to be tested asap). This is just an update and if you have any input, it'd be appreciated. THX

 

just thought Id do one more update, first off using less than 12v on sf-hc25g in the NC connect section was causing issues. I elected to use a 24v to 12v buck converter, mainly because i thought i might have to use my 12v relay board, so 24v with appropriate resisters in my optoisolator circuit prob would have been fine..... All that said, with a minor change to Black Box firmware and my optoisolator AUTO signal generator circuit and using a slightly modified grbl laser post processor in fusion 360, I am now able to generate a cut path that waits for arc start to begin moves like a professional machine and have full THC.... goal achieved... I have metal on order for water table...... any comments or questions let me know, id like to pass it on.

 

Hello,
I've just completed the assembly of my pen plotter made with Arduino and CNC shield.
The plotter is behaving erratically, as a total beginner I'm struggling to even find where to start the debugging process.
I use Grbl controller 3.6.1 and the build info is 0.9i
I've been through the wiki and doing as much research as I can, but the amount of information to process is a bit overwhelming.
If anyone could share some ideas about how to start the debugging process it would be very helpful.
Thank you

 

Can you describe what you mean by erratic?
Did it ever work correctly?

 

I could draw something but I can't repeat the process.
Now I have an "alarm lock" message, I can disable it using $X but I'm not addressing the root cause.
All I would like to be able to do at this stage is to be able to start from the home position and draw a rectangle around an A4 sheet of paper.
As a side note, I could press the buttons in Grbl Controller making the servos move but I can't repeat this action all the time.
Sorry for not being able to narrow down the scope further, I'm at the stage where I have lots of unknown unknowns.

 

What are you using to generate the gcode? Are you just trying to move the motors manually? When you try to move the motors manually do they move as you expect?

 

• moving the motors manually using Grbl controller is not resulting in what I expect. Sometimes they move, sometimes they don't. Sometimes the pencil holder is hurting the steel rods in a repetitive way.
• In order to generate the Gcode, I started by using the code provided by the seller on Aliexpress (I could draw it twice but not from the home point). I've also tried to generate the Gcode using Inkscape and extension (trying basic stuff first like making a rectable in the center of the A4 sheet)

 

Are you using openbuilds CONTROL to move motors manually/ execute gcode? Or a different software?

 

Can you please post a pic of your cnc shield showing the version number as clearly as possible. It might say protoneer on it, but that doesn't necessarily mean that it is genuine.
Grbl V0.9 is rather old, and leads me to suspect that your shield is an out-of-date copy rather than a genuine Protoneer. I don't use Openbuilds Control myself, but I believe there are significant issues with older versions of grbl.
Alex.

 

I was using "Grbl Controller 3.6.1" but now I use openbuilds CONTROL v 1.0.331
When I click on Y+ /Y- or X+/X- I got much smoother movements but both axis move at the same time

 

Here is the link to the picture, I don't believe it's a genuine protoneer as I purchased this plotter on Aliexpress, being the cheapest plotter I could afford. Also OpenBuilds controls shows it as "CH340 Arduino Fake Com3".

I have now flashed my Arduino board, I now use v1.1h

The plotter moves smoother on both axis however when I try to move on axis, both move at the same time

 

I am not sure this is your issue, but I had issues before using the ch340 ch arduino and had to go with an atmega 328 version of the uno. If I remember right, I think the ch 340 can get bogged down with the speed/complexity of some files. I never had any issue making basic movements with the 340 as you describe though.

Have you checked the wiring? Is it possible the wires are touching?

 

Not 100% sure here is a picture of the pen plotter I believe it's a CoreXY one

 

wires look ok

It looks like the issue appeared since I upgraded the firmware to 1.1h

I've just made a test with Universal Gcode Platform, if I click the diagonal move button my plotter will move in a straight direction. Whereas if I click a regular arrow, it will go in a diagonal direction.