Job simulation causes actual movement

I had a weird bug last night. I have the option enabled where when I load a job it simulates it in the little preview window to make sure it doesn’t exceed the soft limits. Last night I loaded a job and the head just started moving. It fired up the spindle just as it was plunging into the material, so it didn’t break my bit, but I have a VFD so it wasn’t at full RPM either.

I have a Genmitsu grbl controller. I have seen other times where when I loaded a file the head started to move, but I usually have it parked near home when I load the job so it never has a chance to actually get to the material before I stop it. This time I was lined up on zero and the Z was low because I had just probed so it just dove down and started cutting. Scared the crap out of me actually.

Is this a known bug that the simulation can sometimes trigger actual machine movements? I’m going to have to turn that feature off now, as it’s dangerous.

@dan203 I’m assuming you mean the ā€œrun check mode on file loadā€ option?

Yes, I couldn’t remember the actual name and I’m not in the shop so I couldn’t check the controller. But it’s the feature where when you load a file it runs a simulation of the full job in the little preview window. For some reason it occasional causes actual commands to be sent to the controller and start running.

@dan203 I never used that option. I just enabled it and loaded a file. It ran the check but I didn’t see anything in the visualizer. Does typing $c in the console do the same thing?

@dan203 I just disabled that option and now every job I load cause gSender to turn white. The whole application not just the visualizer. Reboot didn’t help. Gonna investigate. gSender 1.5.7

Weird.

I turned it on because I had to set soft limits on my machine because my dust boot will hit the sides if I allow the full throw of the limit switches. This just ensures nothing I load will exceed the soft limits before I hit go.

Well this is weird. I noticed that the top of gSender, where it usually says ā€œidleā€, it now said ā€œcheckā€. And this even though the option was disabled. I retyped ā€œ$Cā€ in the console and it now say ā€œIdleā€ and I can load a job again. I’ll try a few more tests to see if I can see a simulation in the visualizer

@dan203 I loaded a bigger file and this time I saw the simulation in the visualizer. The previous job must have been too small for me to see anything.

That said, a few jobs that I loaded generated an error and gSender was stuck on ā€œCheckā€. Had to type $C to get back to idle.

Unfortunately, I can’t help you for your actual problem. If it did start moving the spindle, it is definitely a bug and Sienci may respond here. They will want you gSender version though.

1 Like

I’m running the latest release version . 1.5.something

We didn’t see this in testing, but have already sort of addressed it in Edge - we made it so that you are now prompted to check or not on job load instead of it happening automatically and added some extra guards to guarantee that the firmware is in Check mode before any code is sent. Just a bit of a UX requirement that was originally missed.

It’s only happened a couple of times, but it’s scary when it does.

Why do you need to send commands to the controller at all when simulating? Isn’t that something you can just do in the software itself to make sure you it doesn’t hit any of the limits?

Check mode is a firmware feature - it simulates the file without moving the motors.

Then my Sainsmart controller seems to have issues sometimes and misses the simulation request.