PROBLEM - Uneven engraving from left to right

[Gerti Singer]

Hello this is my first post as a "Hello" to the forum

Well we bought a new GWeike LC6090 60W working on RDcam/Laserworks v8 and are happy with the support we got so far. The problem is that now that we are at the stage where it should start working, we cannot use it because there is a problem with the engraving (or maybe cutting as well).

- The table has been leveled to the gantry
- The laser allignement has been made (although I did not change the 3rd mirror allignement, since I placed it out of focus to make a large circle and then focused it made a perfect little dot completely in the center of it, so I presume it is ok).
- The screws are tightened (although not for the belts, do not know yet where to tighten them).

Well I have attached the pictures of what is happening. As you can see the machine starts making lines from left to right and on the left it starts a little to late to power, so it always leaves material before it is in full power. At higher speeds it is really evident, at lower less. But the thing is it looks like the laser does not get instant power when powered, but gets it with a slight delay (just though of it now, when writing

The last clue I can give to the technical detectives, is that the beginning anode of the tube is slightly cracked as on the picture, but is that reason enough for the problem, or is it a simpler solution to this problem, because I would not prefer to jump to conclusions. The tube will be replaced by GWeike, not their fault. Thx to Lucy for great support.

Speed 200/15 or 300/20. 0,042 interval, so 600 dpi on the newer two pictures without info.

Really looking forward to all your help

Photo 21-09-15 18 56 48 (1).jpgPhoto 21-09-15 18 57 01 (1).jpgPhoto 24-09-15 19 16 01.jpgPhoto 24-09-15 19 39 18.jpgPhoto 22-09-15 15 03 02.jpg

[Joe Pelonio]

Not being familiar with your machine, I can't say what's causing it, but have a suggestion to get the work done. Try adding to the file a vertical line off to the far left of the material. It should try to start there and fire again when it gets to the actual graphic. If you don't want that line to appear on the material, place a sacrificial scrap of something over that area.

[Richard Rumancik]

Gerti -welcome . . .
Does the laser do the same thing if you place the image justified to the right side of the bed? If it does the same thing then it would seem there is some kind of problem with the laser triggering.

If it appears okay on the right side of the machine, then I would suspect beam alignment - the beam could be hitting an obstruction on the left and become diffused, hence a fade-in start to the lasering. When you talk about a "large circle" and "perfect little dot" are you talking about the actual CO2 beam print, or are you talking about a red diode indicator? A red diode won't prove conclusively that the actual CO2 beam is aligned perfectly.

[Gerti Singer]

Joe: Interesting proposition. Tried it, does not work
Richard: The table is perfectly leveled with the gantry. I meant that I fired the laser higher from the table to make a large circle and did not move it and then fired it focues again. The small focused needle point was completely in the center of the out of focus large circle. So alignement ok.

It might be a power triggering problem i presume, we will see.

[Mike Troncalli]

If you machine is new and under warranty then I would get that tube replaced ASAP.. Not saying that it is or isn't the problem, but you have a known issue with the tube and it can't do anything but get worse over time.

[Matt McCoy]

Joe: Interesting proposition. Tried it, does not work
Richard: The table is perfectly leveled with the gantry. I meant that I fired the laser higher from the table to make a large circle and did not move it and then fired it focues again. The small focused needle point was completely in the center of the out of focus large circle. So alignement ok.

It might be a power triggering problem i presume, we will see.

Hey Gerti,

You might have cursed me. I just literally ran into a similar issue with my design of thin concentric circles that I engrave on cork at 1% power. The top and bottom looked great, but the widest parts of the design were very faint. This is something that I have engraved without issue many times before. It didn't matter what size I scaled it, recreated the file, or upped the power. I ended up increasing the stroke from 1 to 2 point and that fixed it. Suits me and looks better. I'm not sure if this helps, but I suspect the tube has degraded a little.

[Gerti Singer]

Thanks Matt,

I will replace the tube on Wednesday and try that first and then try your trick as well. We will see. I will definitely update with the solution

[Gerti Singer]

UPDATE:

Problem solved, the problem was the tube and also the alignement, especially the third mirror.
I still think it is a bit off because it cuts 7 mm acryl under an angle.

[Kev Williams]

before adjusting that mirror, cut some 7mm wood and check the angle of the cut...

[Keith Winter]

Looks like I might be late to the party. However I had a problem similar to this a couple weeks ago, it was due to the alignment being off as well.

You didn't mention the lens you were using, but 7mm cut with a 2" lens will be at a slight angle. Should be the same angle all the way around, if it's not then you may need to do further alignment. One thing that helps is to focus 1/2" down between the surface and the bottom of the substrate to cut down on the lens angle issue, or use a bigger lens.