Author Topic: Machine stopped mid job????/  (Read 181 times)

bob2299

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Machine stopped mid job????/
« on: August 15, 2019, 05:07:07 PM »
I am in middle of 5 hour burn on a turned 9 inch maple platter and my machine suddenly stopped.  My computer is dedicated to laser use only, so should not be any interference.

Any suggestions as to what might have happened and is there is a way to restart and finish the job? 


Bob
-EleksMaker A3 2.5 W Laser with Mana SE board & air assist
-Inkscape, Qcad, BCL, &  T2
-Ender 3 3D printer
-I live in London, Ontario, Canada and my interests are inlay/marquetry & 3D printing

Zax

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Re: Machine stopped mid job????/
« Reply #1 on: August 16, 2019, 04:32:28 AM »
Did you get an "error" from the laser? This indicates Grbl has detected a problem, usually due to a memory or USB fault. Was the Nano warm/hot?

The latest Chinese Nano's use a clone micro-controller with really low quality memory. It could also be caused by electrical interference, the USB driver going into a power-saving mode or something like that.

Recovering the job is unlikely as when Grbl goes into an error state it doesn't keep track of position (because it immediately stops the motors rather than decelerating).

bob2299

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Re: Machine stopped mid job????/
« Reply #2 on: August 16, 2019, 06:52:18 AM »
Thanks Zak, but no error messages on computer screen or on T2 screen, everything just stopped.

I will try to recover by re-running the job but with laser beam off.  Once I get to the point where the job stopped I will reactivate laser beam and continue the burn. 
-EleksMaker A3 2.5 W Laser with Mana SE board & air assist
-Inkscape, Qcad, BCL, &  T2
-Ender 3 3D printer
-I live in London, Ontario, Canada and my interests are inlay/marquetry & 3D printing

ggallant571

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Re: Machine stopped mid job????/
« Reply #3 on: August 16, 2019, 06:59:31 AM »
1. Clamp the disc to the fixture to keep the registration.
2. Coat the disc with brown painters tape to act as a waste test media.
3. Edit the image to erase the currently etched region.
4. Test burn on the painters tape at lower power.

When I do large round discs I 3d print plastic brackets which are screwed into the fixture wasteboard, I edit the image to isolate independent shapes and etch separately. Each image is the same size so a homing operation gives fairly good results. If you don't have limit switches etch a pattern to at as a manual known good reference spot.

Good luck!!!!!!
SARCASM - Just one more service we offer here.

bob2299

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Re: Machine stopped mid job????/
« Reply #4 on: August 18, 2019, 08:44:43 AM »
Thanks for the tips.  Iwas able to save the job by re-registering the file, rerunning the file and turning the laser beam off until it reached the stop point, then tuning the beam on for rest of job.  I will post a picture once I get the platter finish applied.

Like your suggestion for future jobs, particularly breaking big job into several smaller ones.

I have 3d printed lifts to raise the laser engraver.  Diferent height lifts would give me better laser focus whereas the way I did it as single burn the focus range was at its limit.

In any event need more work on my technique.

Bob

Photo attached - platter is 9.5 inch diameter and is Box elder (Manitoba maple) with Tung oil finish.  Lousy photo, but you get the idea.
« Last Edit: August 27, 2019, 03:12:42 PM by bob2299 »
-EleksMaker A3 2.5 W Laser with Mana SE board & air assist
-Inkscape, Qcad, BCL, &  T2
-Ender 3 3D printer
-I live in London, Ontario, Canada and my interests are inlay/marquetry & 3D printing

ggallant571

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Re: Machine stopped mid job????/
« Reply #5 on: August 18, 2019, 06:26:17 PM »
There is no how-to book of laser etching and if there was is probably wouldn't apply to my setup. Glad to hear you were able to salvage the project.

I put small uninterruptible power supplies (UPS) on the bench for laser etchers and 3D printers. We have a whole house generator that takes about 15 seconds to kick in so the $50US from Staples works fine.
SARCASM - Just one more service we offer here.