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Kate Rose
11-06-2017, 9:54 AM
I'm hoping someone here can help me. (I did not find the answer to this in other threads that I searched, though I may be overlooking it.) My issue is that I have a 50 watt Chinese laser that cuts and engraves in Dot and Pen modes, but not in Cut mode. When I press the test button, nothing happens with the laser, but the laser is obviously functional because it works in the other modes. Additionally, when I go to make cuts, it engraves a shallow line in the path the head follows to get to my first actual cut. This means that I end up with a sort of drag line across the project, which obviously is not optimal and ruins some of my projects altogether. I am using the included RDWorks software; I'd be happy to switch to CorelDraw or something else if the software is the problem, but I don't want to invest money in that and still not fix the problem.

Thanks for any help or Insight you can give me, this is driving me crazy!

Bill George
11-06-2017, 1:27 PM
First has it ever worked correctly and maybe I am missing something but my machine has a raster or engraving mode like used with some graphics and pictures and a vector line drawing or could be cutting mode. If the laser head is on when its positioning itself to do the work I have no idea. What brand of machine and was there any type of manual with it? It has nothing to do with Corel Draw which is just a graphics program.

Kate Rose
11-06-2017, 1:46 PM
First has it ever worked correctly and maybe I am missing something but my machine has a raster or engraving mode like used with some graphics and pictures and a vector line drawing or could be cutting mode. If the laser head is on when its positioning itself to do the work I have no idea. What brand of machine and was there any type of manual with it? It has nothing to do with Corel Draw which is just a graphics program.

Thanks for your reply! The machine is a Shenhui (one of the ubiquitous ones everyone seems to get on ebay), and the manual is pretty much useless. It did cut fine at first, then the Cut mode stopped working after a few months. I did not change any settings or anything, it just wasn't working one day when I went to use it. Since then, I have tried different settings, and I asked about CorelDraw or similar because it seems a lot of people have issues with the included software doing strange things.

Bill George
11-06-2017, 2:54 PM
Well if it worked one day and not the next, perhaps the mirrors are out of alignment or the lens is dirty or loose in the holder. You might try those two things first but it could also be a lot of other things. Start with the simple.

Kate Rose
11-06-2017, 3:04 PM
Well if it worked one day and not the next, perhaps the mirrors are out of alignment or the lens is dirty or loose in the holder. You might try those two things first but it could also be a lot of other things. Start with the simple.

Does that make sense if the Dot and Pen modes are both working? I don't know how to test the mirror alignment if I can't even get the laser to fire when I hit the Test button.

John Noell
11-06-2017, 3:55 PM
1) I would suggest contacting John Wang (johnlaser@163.com) at Shenhui to see if he has any advice. He can be helpful.
2) There is a very good translation of the RDWorks manual by the guys at RDWorkslab.com (They can be a bit crusty when annoyed and they have made registering for the forum [a requirement for access to the manual] a bit tedious. Just read the instructions CAREFULLY.)
3) There is a new program under development, called LightBurn, that should be out this month. The programmer is an extremely talented and qualified American. LightBurn works with a variety of controllers, but is aimed squarely at the Ruida controllers (used by most if not all Shenhui lasers). I find it (the beta version) much easier to understand than RDWorks.

Kate Rose
11-06-2017, 4:04 PM
1) I would suggest contacting John Wang (johnlaser@163.com) at Shenhui to see if he has any advice. He can be helpful.
2) There is a very good translation of the RDWorks manual by the guys at RDWorkslab.com (They can be a bit crusty when annoyed and they have made registering for the forum [a requirement for access to the manual] a bit tedious. Just read the instructions CAREFULLY.)
3) There is a new program under development, called LightBurn, that should be out this month. The programmer is an extremely talented and qualified American. LightBurn works with a variety of controllers, but is aimed squarely at the Ruida controllers (used by most if not all Shenhui lasers). I find it (the beta version) much easier to understand than RDWorks.

Thanks very much! I will email John Wang and check out RDWorkslab.com . I'll also keep my eye out for that program; maybe that will be better for me than RDWorks. I feel like I understand RDWorks, generally, but it is not the most enjoyable program to use, for sure.

Bill George
11-06-2017, 4:34 PM
You said: Does that make sense if the Dot and Pen modes are both working? I don't know how to test the mirror alignment if I can't even get the laser to fire when I hit the Test button.

Have you ever aligned the mirrors? Did the Laser fire button on the panel fire it before? Not having enough power to cut is one clue. As I recall you have to have a power level entered either in the last software you ran or on the keypad. I can almost guarantee you if you have never checked the mirrors and lens before that would be a very good place to start. Once again, it could be a lot of things, but start with the simple.

Matt McCoy
11-06-2017, 4:38 PM
I agree with Bill. I would check mirror alignment and lens first. If you have not changed software settings, next would be tube or power supply.

Hope that helps.

Kate Rose
11-06-2017, 4:43 PM
You said: Does that make sense if the Dot and Pen modes are both working? I don't know how to test the mirror alignment if I can't even get the laser to fire when I hit the Test button.

Have you ever aligned the mirrors? Did the Laser fire button on the panel fire it before? Not having enough power to cut is one clue. As I recall you have to have a power level entered either in the last software you ran or on the keypad. I can almost guarantee you if you have never checked the mirrors and lens before that would be a very good place to start. Once again, it could be a lot of things, but start with the simple.


Yes, I had the mirrors well-aligned and had no problem with the laser test-firing before it mysteriously disappeared. I have tried it with the power set as high as 95%, which is significantly higher than I had it when it was actually cutting properly. Thanks for the additional suggestions!

Bill George
11-06-2017, 5:36 PM
So if you have aligned the mirrors and checked the lens. Now your getting into the major expense part of troubleshooting. But before you do that, check for loose connections with a screwdriver please, with the machine unplugged, not just looking. Tighten all those connections on the controller, power supplies and HV power connections. Even on the tube. IF you have lost power and can no longer cut its very important all the connections are secure. Yes they can appear to be working fine and still be loose or sometimes not even plugged, in.

After you get done with all that there ways to check the tube and power supplies. Remember if you skip a step or just do not do it mistakes are going to cost you money. Have you contacted the people you purchased from, tubes and power supplies if needed can be expensive and should have a warranty.

Kate Rose
11-06-2017, 5:46 PM
Thank you, Matt, and thanks again, Bill.

I've changed the tube, which was bad, and the power supply, which didn't change anything. I've also tightened everything, but I will go through and try again.

Bill George
11-06-2017, 6:43 PM
Thank you, Matt, and thanks again, Bill.

I've changed the tube, which was bad, and the power supply, which didn't change anything. I've also tightened everything, but I will go through and try again.

Well I guess you should have told us that information up front. Changes things, once again check the wiring and how did you know the tube was bad, and the power supply also?? So both those parts were changed as a set? Furnished or purchased from where?

Kate Rose
11-06-2017, 6:55 PM
Well I guess you should have told us that information up front. Changes things, once again check the wiring and how did you know the tube was bad, and the power supply also?? So both those parts were changed as a set? Furnished or purchased from where?

I'm sorry, Bill, I don't know what information is helpful and what's just extraneous, but I do appreciate your help.

The tube had water where it shouldn't, and electricity was arcing to the case, and nothing else was happening. I did not know whether the power supply was bad, but it was an easy and inexpensive thing to try changing. Both the tube and power supply came from ebay, and were not changed at the same time (about a month apart).

Bill George
11-06-2017, 8:01 PM
I'm sorry, Bill, I don't know what information is helpful and what's just extraneous, but I do appreciate your help.

The tube had water where it shouldn't, and electricity was arcing to the case, and nothing else was happening. I did not know whether the power supply was bad, but it was an easy and inexpensive thing to try changing. Both the tube and power supply came from ebay, and were not changed at the same time (about a month apart).

It could be wrong parts, wired wrong, bad controller or keypad or anything. I guess I have nothing else to add. If you can find someone in your area to troubleshoot, I would take it to them otherwise? When asking for help, list ALL the details.

Kate Rose
11-06-2017, 8:20 PM
It could be wrong parts, wired wrong, bad controller or keypad or anything. I guess I have nothing else to add. If you can find someone in your area to troubleshoot, I would take it to them otherwise? When asking for help, list ALL the details.

Okay, thank you for trying to help.

Dave Sheldrake
11-07-2017, 6:51 AM
SH350D

If the tube was dead and the PSU died then you may have a cascade problem. Did you run the new tube on the old power supply?

Was the new power supply adjusted to put out the correct current (at default they pump 35mA, ie: more than enough to kill your tube)

How long is the tube? from memory the 350 won't take a true 50 watt without an extension so I'm betting it's an overdriven 40 watt

Bill's right, at this point it could be absolutely anything electrical in the machine and/or badly aligned optics

Kate Rose
11-07-2017, 8:47 AM
SH350D

If the tube was dead and the PSU died then you may have a cascade problem. Did you run the new tube on the old power supply?

Was the new power supply adjusted to put out the correct current (at default they pump 35mA, ie: more than enough to kill your tube)

How long is the tube? from memory the 350 won't take a true 50 watt without an extension so I'm betting it's an overdriven 40 watt

Bill's right, at this point it could be absolutely anything electrical in the machine and/or badly aligned optics

The PSU never actually died; I replaced it in the hope that it would somehow magically fix the problem. The new tube (800mm) was used on the old power supply and the new one, and the machine ran exactly the same with both. I made no adjustments to the power supply.

Thank you very much for your help. I posted in the hope that it was some sort of, "Oh, this is the problem, and if you do A, B, and C, it will be fixed" type of problem, but clearly this is far beyond my realm of knowledge. I'm going to see if I can find someone locally who knows about these things to come take a look at it.

Matt McCoy
11-07-2017, 9:36 AM
The PSU never actually died; I replaced it in the hope that it would somehow magically fix the problem. The new tube (800mm) was used on the old power supply and the new one, and the machine ran exactly the same with both. I made no adjustments to the power supply.

Thank you very much for your help. I posted in the hope that it was some sort of, "Oh, this is the problem, and if you do A, B, and C, it will be fixed" type of problem, but clearly this is far beyond my realm of knowledge. I'm going to see if I can find someone locally who knows about these things to come take a look at it.

You might check YouTube for mirror alignment. Easy and cheap to mark off your troubleshooting list.

Kate Rose
11-07-2017, 9:47 AM
I will, thanks!

Dave Sheldrake
11-07-2017, 10:20 PM
@800mm the tube is just about a 40 watt, that may be the base of all your problems if the PSU is pumping too much current

Bill George
11-08-2017, 8:51 AM
@800mm the tube is just about a 40 watt, that may be the base of all your problems if the PSU is pumping too much current

Looks to be one of those low cost eBay machines sold as 50 watts. Over driven tube and with poor construction. So it could be anything.

Kel Kodama
11-12-2017, 7:35 PM
If you replaced the tube (which used to cut properly) and didn't realign the mirrors, then I would suspect that the mirrors are the problem. Also, try to install an ammeter (amp meter) to make sure you don't exceed 20mA, which is the maximum that this tube is supposed to handle.

Dave Sheldrake
11-13-2017, 5:19 PM
If you replaced the tube (which used to cut properly) and didn't realign the mirrors, then I would suspect that the mirrors are the problem. Also, try to install an ammeter (amp meter) to make sure you don't exceed 20mA, which is the maximum that this tube is supposed to handle.

Try 16mA, 20 will kill a 40 watt tube pretty quickly