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View Full Version : Laser fires on "Laser Test", but not from software



Simon Arthur
05-20-2008, 12:20 AM
I have a brand new problem with my Artsign JSM40 (very similar to the Rabbit and all the other Chinese lasers).

The machine has been working fine for a while now, though I haven't used it much. When I use the "Laser Test" buttons, the laser fires just fine. Revently, however, when I try to engrave using NewlyDraw, the carriages move, but the laser never fires.

I've tried power cycling both the laser cutter and the computer, as well as re-installing NewlyDraw, and reseating the parallel cable on both ends. None of these solutions helped.

Has anyone ever seen this problem before? Any ideas on what might be wrong?

(Crossposting from CNCZone, where nobody was able to answer.)

Mike Page
05-20-2008, 12:31 AM
Could be a door safety switch?

John Frazee
05-20-2008, 1:24 AM
Have you tried different files? Mine did the same thing a few times and I tried another file and worked fine. Some files it just doesn't like for some reason.

Frank Corker
05-20-2008, 7:50 AM
Are you guys keeping an eye on the temperature of the room that the laser is in. I know that for aircooled systems if the temp is low, laser takes an age to warm up and then fire.

Peck Sidara
05-20-2008, 9:59 AM
Could be a door safety switch?

I would lean towards the interlock switches as well. If the display of your laser has a "laser test" button then this button likely bypasses the interlocks and sends a signal directly to the laser tube to fire.

I don't beleive it's caused by your software or parallel connection because it sounds like the job is making it to the laser and the laser is reacting to the job by moving accordingly, just no laser beam.

HTH,

Richard Rumancik
05-20-2008, 10:50 AM
I don't know if this laser maps color to speed/power like conventional laser engravers, but is it possible that you have inadvertently set a very low power setting where it just appears not be to firing? (Or used an "illegal" color in the file?) Does it occur with older files that were known to work previously?

David H. Mitchell
05-20-2008, 11:18 AM
Check your file, if you have text, that has not been converted to a curve. It will react the same way.


Dave

Simon Arthur
05-20-2008, 12:13 PM
Thanks for the input, everybody.

It's not the door safety switch; the "Laser Test" fires with the door closed, but not open.

Previously working files now don't work, and neither do new ones. This laser does not, as far as I can tell, have the ability to allow control of the laser power through software.

I just tried running the machine with a different computer: same results.

I'll will let the machine warm up for an hour or so. Right now, I'm leaning toward a bad control board as the problem.

Update: the warm-up period didn't help.

Simon Arthur
06-02-2008, 9:52 PM
I'm currently taking the path of replacing the control board with a Xylotex stepper controller and the software with EMC. Others have been successful with this in the past:
http://www.synthfool.com/laser/
http://www.routoutcnc.co.uk/Forum/index.php?topic=17.0
http://alastair.d-silva.org/[catpath]/working-with-cheap-chinese-laser-engravers

Richard Rumancik
06-02-2008, 10:33 PM
Simon, if you convert to a Xylotex controller and EMC would this become a vector-only laser? I didn't think EMC had a raster capability as it was developed mainly for industrial machine tool applications.

Simon Arthur
06-04-2008, 10:34 AM
In the end, the only thing any laser machine does is move the mirrors and fire the laser. Moving the beam along the direction of the cut or rastering is all handled via software. I'm pretty sure I can figure out how to generate a set of G-Code instructions for rastering, but it's not a priority for me at this point.

I now have EMC controlling the stepper motors via the Xylotex board. There are still a few remaining tasks: calibrating the motors, aligning the laser, and working out how to control the laser from the parallel port output.