u/rynjh12345

In case you missed, I posted twice here and here:

https://www.reddit.com/r/lasercutting/comments/1thpovl/help_diagnosing_a_co2_laser_cutter_tube_lights_up/

https://www.reddit.com/r/lasercutting/comments/1thrr45/co2_laser_not_cutting_followup_video/

I bought a 40 watt co2 laser cutter from Facebook marketplace (first mistake) and didn't have the owner show me it working before I bought it (second mistake).

I have never actually used a laser cutter before, so I wasn't sure what was normal, but I was having trouble getting it to engrave anything. I thought maybe the mirrors were not aligned, but I was having a lot of trouble getting burn marks to show up on the pieces of tape I put on the mirrors to check alignment... In fact, I could barely get the laser to burn a piece of tape when put directly in front of it. Needless to say, the tube was dead.

~$200 later, my Amazon replacement arrived and holy cow what a difference. I put some tape on mirror #1, pressed the test fire button for a fraction of a second and my garage was illuminated by the flame produced by the incinerated tape. I guess that's how its supposed to be... These things are no joke.

I hope I'll have some more projects to share, but figured I'd at least give everyone a quick update.

Thanks!

Can’t seem to post a video in the comments of my other post (https://www.reddit.com/r/lasercutting/comments/1thpovl/help\_diagnosing\_a\_co2\_laser\_cutter\_tube\_lights\_up/), so here’s a follow up

As you can see, current registers on the meter, but no burn mark shows up on the tape. I'm assuming with this level of current, you should quickly see the tape burn through? Does the fact that current is registering confirm the power supply is fine and the problem is more likely the tube?

Hey all,

Recently purchased a k40 style laser cutter used. Did not have the seller prove to me it still worked, so I’m stuck trying to figure out if it’s not working because of user error or if a component is bad. I’m new to laser cutting so I would assume the former until proven otherwise.

Essentially what I’ve observed is that when I press the test fire switch, about 1 in 10 times I will see a slight burn mark on the piece of wood I have under the laser. Most of the time I get nothing. I thought maybe mirrors were misaligned, however, putting double sided tape on any of the mirrors in any position yields roughly the same results. 9 times out of 10 no mark, but every once in a while it will burn through.

The tube definitely lights up every time. I’ve attached a video, I’m not sure if it’s considered bright enough, but it’s definitely glowing. However, putting a piece of tape right in front of it on the very first mirror only occasionally results in a burn mark. Most of the time I get nothing.

Do I need to replace the tube, or could there be another issue here?