Starting problems with CO2

So hello guys/girls,

for three years im using 5w diode laser and i want to step up.
So i buy chinese 80W CO2 laser from Vevor.
And im in shock how different and hard to set up it is(even if i saw ton of videos of how to set it up).
But everything run smooth so far.

But i have three guestions:

1. Is the laser tube in right position?

Shouldn’t be the silicone tube at the end of the laser tube facing upwards? Bcs it seems the pump doesn’t get water in tube.

2.Today i get finally some decent ventilation so i try to run the cut test.
It’s plywood 3mm

To me it seem’s like it have lack of power.
Or is it normal for 80W laser to cut 3mm ply only in 42mm/s?

3.From beginning im getting these holes in starting/ending positions.

Lines are perfect.
But at the start/end it makes a hole trought material.
Is it a problem of Lightburn or ruida setup?

Thank you for helping.

Sorry for my rubish english 🙂

Have a nice day Michal.

Hi Michal,

The tube does appear to be in the right location, but if it were me, I would try to avoid having the silicone coolant tubing contact the glass tube. I run my tube under the laser, rather than over it.

Water should definitely be flowing. If it isn’t, stop and reassess. Wrecking a tube is neither fun nor cheap.

Your power vs speed will take some getting used to, and it varies from laser to laser, so it’s hard to say if your setup is over/underpowered from an outside perspective. If your mirrors are only partially aligned, you will have some power loss. Getting the alignment perfect is absolutely worth the time investment.

As for the results you see, it appears that your power/speed settings are off. LightBurn will ramp the power down for corners, as the reduction in speed to navigate a corner means that if power was left at the full rate, it would burn extra deep in the corners. Try reducing the Min Power % setting by 5-10%, and increase your Max Power % until you get cuts through (don’t go over 85%) Or alternately, drop your cut speed.

I think the output should have the coolant come out the top so any air will be purged from the tube. Can’t really see how it’s coolant is exiting the tube from the photo.

Old tube on the left, replacement on the right. Both have the coolant output up…


I’d make book that the machine isn’t properly aligned.

  1. properly working tube
  2. clean and aligned optics
  3. proper focus

If you have these three they work… That should cut through 3mm like butter…

If you have an issue with alignment, try this video from Russ Sadler…

Good luck

:smile_cat: