View Full Version : Can engrave but not pulse the laser

Shawn Morris
08-12-2014, 9:07 AM
I am new to this hobby and purchased a used Sh-g350 laser enngraver. The mirrors need alignment but the laser button on the control panel does not fire the laser. I get the beep when the button is pressed, and I see a brief flash in the laser tube, but no laser output. If i start a cut or engrave job, however, the laser works, it's just out of alignment. I can't really align it without having the pulse. Has anyone here seen this issue or have suggestions?

Mike Null
08-12-2014, 9:27 AM

Welcome to SMC. If you have checked out this thread I suggest you do so as it may answer questions for you.


Ken Shea
08-13-2014, 10:02 PM
When you run the program for the engraving it sets the power but from the panel you need to set it manually, mine needs to be at least 12% to fire the laser, this is typical.

Of course that may not be youe problem but it's easy to check.


Rich Harman
08-14-2014, 1:35 AM
Another thing to check is the duration that the laser is set to fire. On mine a setting of "0" means that it fires for as long as you hold the button. If it was set too low the "on" time may be too little for it to do anything. I usually use 100 which is 100 milliseconds, which is 1/10 of a second.

Shawn Morris
08-14-2014, 8:08 AM
Ken and Rich: thanks, that is along the lines of what I was thinking. Unfortunately my machine hasn't made it home yet and is still at a friend's house 120 miles away. Is setting these parameters intuitive for a noob like me? I see the idle interface in the manual shows max power and run speed. Is this where those items are configured? I have a few issues and I'm trying to resolve them one at a time. This seemed like the place to start. Thanks again for the help, I'll keep researching.

Ken Shea
08-14-2014, 8:46 AM
No one hates to read (don't confuse this to think I cant :) ) more then I do but reading the manual on setup and operation is a must, even doing that it was one hurdle after another and I'm still jumping :(

Others I've read just seem to move ahead with no trouble at all it seems, were just lucky I guess LOL.


Shawn Morris
08-14-2014, 9:04 AM
True, but I find the manual is either vague in many areas, or maybe it's my comprehension. I know that the translation from Chinese to English doesn't help that either. Reading is about all I can do until I get back in front of the machine to try again. The pulse issue I would like to resolve first, but if not, I will proceed with the alignment without that function. I can still send a job to pulse the laser from laserworks.

George M. Perzel
08-14-2014, 12:29 PM
I had the same problem with my Shenhui
Talked to the service guy in China who told me to run a ground wire to the metal part of the flow check valve-has worked ever since
I kid you not.
Best Regards,

Shawn Morris
08-14-2014, 2:36 PM
I'll definately give that a try. Thanks