[amy_stars]

Hello,
I am cutting something for a customer using an LS3020 using newlydraw. The design has some engrave detail. When I have sent it to cut and it has finished, the engraved lines are doubled as though it has engraved the same lines twice about 1mm or less apart from each other. I have never had this issue before. I have checked the drawing and there seems to be no duplicated lines. Does anyone know what is happening?

Thanks
A

[TechGraphix]

can you engrave unidirectional and have the same result?

Kees

[Melody-gweike]

Have you checked the beam alignment? Sometimes if the beam has some problem, it has issue like this. Please take off the lower cone part of laser head and test to see if it is one line.

Melody
[email protected]

[amy_stars]

I have engraved 3 lines, left to right engraves a double line nearly on top of each other. Up and down engraves 2 lines either side of each other, Diagonally does the same as up and down.

I also took off what I think is the lower cone of the laser head (undid a screw that then let me remove a metal cone shape attached top a tube)and then engraved, it made no difference.

Any suggestions???

Thanks
A(flame2)

[Bec Weir]

Are you trying to cut a thin a line as possible on the drawing program or is the line thicker and it is cutting both sides of the line.

Does your air assist have a nozzle that can get in the way of the beam?

[amy_stars]

Hi,
Cutting is fine, when I engrave 1 thin line it is engraving double, it never used to. I can not see anything getting in the way of where the laser comes out.

[keebler303]

It sounds like the beam is reflecting off something and then you get two different spots. It could also be something like a loose belt or something giving you backlash but the way you have described it I think the problem is in the optics.

Matt

[amy_stars]

Thats what I was thinking but am unsure what to do about it? should I be cleaning something? I have propan 2 ol

[keebler303]

Normally it means the beam is hitting the edge of the nozzle and giving you 2 points. You probably should check that the beam is centered on the lens and that the beam is parallel to the axis of the nozzle. I attached a sketch to show you how the beam could be partially reflected off of the inside of the nozzle.

It could also be from a dirty lens or something else in the beam path which is causing the beam to be split into 2. A cracked lens or mirror might do it.

Matt

[lucylucky]

so professional answers, how about change new lens, mirrors, then adjust laser beam path again?

[Smonson]

Amy, you've said a couple of times that engraving causes an doubling effect but cutting is fine (producing a single beam impact). If that's the case, then I don't see how this can possibly be an alignment issue. It could only be a software issue.

From the machine's perspective there's no difference between cutting and engraving.

[EXLASer]

Hi,

Find the problem from the optics or the acc space .
If you are sure your optics is well enough . Make a single-track engraving and a bi-dir engraving and compare these two effects . Modify acc space in engave from options .The engraving effect will be improved .

XYZ Machinery

[MonoNeuron]

It sounds like a couple of your belt pulleys have come loose giving you a bit of backlash. I would go around the machine and check all of them for tightness as this would cause the double engraving but you wouldn't notice it when cutting as you are only following 1 line.
There is a lot of difference between cutting and engraving if you use bidirectional engraving as the speeds are far greater and more backlash will show up, or even belt stretch, if the belts are small enough.
That's my best bet, a loose pulley on each axis.
Rich.

[Things]

Your laser could also be running in a TEM01 or TEM20 transverse mode, however once it's focused down the separate beams shouldn't be obvious. How about a close up picture of the lines, it may help.

[pyrocrafter]

Just wondered if this was ever answered. My engraver is doing exactly the same thing. Double lines when engraving. I assumed it needed a new lens as it's been working perfectly for over 2 years and nothing has been altered. I've also ordered a new reflective mirror as well. I tried re-alligning the 'laser beam' and made things 10 times worse. I think I've now got it back to the way it was before messing with it though.

[MonoNeuron]

Funny thing is when people resolve issues they get all happy and start using the machine and forget to come back here and say whether it worked or not.
:-)
When I had this issue a few years ago I tried every thing to fix it. Swapped out the motors, pulleys, lens, new rails, new belts, mirrors, checked all the alignments and still did not fix it.
I was using a toroidal transformer with a full wave bridge rectifier and a 15,000 mF Cap for my power supply and decided to swap that out for a switch mode power supply and then the problem went away. Don't ask me how a new power supply can fix a double line because I still don't have an answer for that . It was my last resort and it cost just $29 for a 48 volt 10A one. 1/3 of the price of the toroid etc. I now have all fancy switch mode power supplies on my machines and a drawer full or really expensive toroidal trannies.
It's a long shot but that's what fixed mine.
Rich.

[pyrocrafter]

Thanks for that. I'll try the new lens when it eventually arrives and a new mirror. I do actually have a spare power supply in my cupboard because I thought mine had packed up over the Christmas holiday but it turned out to be a broken lead. I did try another lead to start with but coincidentally that was broken too - weird!

Anyway, if I do get it sorted, I'll report back here to help others.

[pyrocrafter]

Found out why my machine is engraving double lines. After spending a lot of money on new lenses and reflection mirrors, which did nothing, my son suggested the tracks that the laser runs across needed a good clean as it would be hindering the smoothness of the action. This would probably solve the problem for others but it wasn't the exact remedy. I noticed, where I mostly used the laser in the top left corner the bar was very slightly out of straight (barely noticeable) where it's gradually worn away over the years.
I'm now engraving Top right and everything's fine So, if anyone's interested in buying my Chinese laser engraver for spares, I'm open to offers.