Laser tube down

I was at the hive earlier trying to cut some card stock with the laser cutter to make stencils for a charity event tomorrow. I couldn’t even get the laser to make a mark on the paper. I’m thinking the tube is dead and we need to order a new one.

In the meantime, does anyone have access to a laser cutter that I could use tonight. The cut will take about 3 minutes total. I’m trying to use an exacto knife now but my hands are killing me.

We can order a new laser tube but obviously we wont have it for my event tomorrow morning. Can anyone help?


I'm coming in to the Hive after work to give the laser a look. Sounds like it's out of alignment again. I'm going to bring some tools to lock the lens in place, and after that see if it needs a new tube.

For reference, FS lasers uses this site to list replacement parts:

Might also want to try cleaning the lens & mirrors w/ Alcohol & q-tips.

The lens comes out, by unscrewing the ring that is holding it down. There is an O-ring between the ring & the lens. If you take the lens out make sure you put it back into the holder in the same orientation it was removed. I believe ours has the more curvy side facing down, but it has been a while and I could be wrong.

I would also check to make sure the red-dot sight is aligned w/ the IR laser beam. It could look like the red dot is centered, while the IR beam is barely hitting the lens.

I don’t know that this is an alignment issue or a cleaning issue. It didn’t even leave a hint of a mark on paper. Grant it, it could just be horribly misaligned or really dirty. But regardless we should probably order a backup tube sooner than later. I would like to get more of a consensus first, and is everyone cool with ordering the 60w replacement tube from the fslaser site? ($600)


That’s what the $0.50 a minute is for, to replace the tubes, right? Might as well have one on hand locked up somewhere.

I wish I had a better source for this, and I wish I had a definitive answer, but I seem to recall reading that CO2 laser tubes have both a shelf life, and a usage life.

Most productive shops will hit the usage life long before the shelf life, but some hobbiests had reported that despite a low amount of usage, the tube had started to decline before they had calculated it should.

I just did a bit of googling, and it is hardly a reputable source, but a post over at cnczone seemed to confirm this:

So, not sure if this is in fact the truth or not, but I would be hesitant to just buy a tube unless we know we need it, or think we are going to need it very shortly. Then again, the above comment could just be BS…

There has also been some comments about possibly looking into getting a higher power tube. The laser we have was apparently sold with an 80W upgrade option. Not sure how much that would cost, or if it would require a different power supply, but that is something else we could look into.

Shadoxx, were you able to put the laser cutter back into commission. If so, thank you very much! If not, still thanks for your effort and is there a definitive diagnosis/estimate of when it should be back online?
In either case, I’d love to learn sometime how to fix the alignment on the machine sometime.

Bill was able to get the laser cutter cutting through quarter inch acrylic yesterday.

He mentioned to Ryan1.0 that the banging of the lid can knock the laser out of level with the chassis – so we may need to look at new dampers for the lid.


We may also want to look into replacing the ‘Door Open’ sensor, it started malfunctioning quite a while ago and was ‘disabled’.

It is a simple magnetic (hall effect?) sensor, we just need to find a replacement.

Another thing I was wondering is if it could possibly matter where the head was when the device is turned off? Like maybe the position should be homed with “reset” before turning the laser off? It’s a long shot, “the door is being closed too hard” seems more likely to be the problem, but maybe it’s a combination of things.

I used it extensively on Wednesday and while Tiffany, Michael and I discussed whether it seemed to be cutting slower in general, I noticed no change in quality over the course of the evening. And then two days later it won’t cut paper for Craig, which makes me wonder how it could have gotten so out of whack by Friday.

In any case, I would like to do whatever I can expand the pool of people who can re-align the laser by learning how to do it, to give Bill a break.

The laser was not out of alignment at first, I don’t think. The real problem was that someone cut a material that fouled up the mirrors. The splitter mirror (that combines the visible red laser with the IR laser was so fouled that it was almost opaque. I used rubbing alcohol to clean it and realign it.

It’s cutting now, but we need to be very very careful as to what we cut… the burned gunk was green in color… and very viscous.

The laser tube was no aligned with the primary mirror when I started looking at it… in fact, the beam was mostly hitting the metal around the mirror. I realigned everything and tightened it all down.

One last thing… the visible red laser is no longer producing a dot… instead it is making a straight line that is out of focus. It appears that it might be bad, but the cutting laser has a good shape… so I wouldn’t worry about it. I will look into a replacement red module.


By the way, I also checked the current draw of the laser… it is well within operating specs so there is nothing wrong with the tube… in fact… I’m astonished that it is as powerful as it is! It’s tuned very well and matched to the power supply perfectly. At 100% power, it is only pulling 20mA… which is dead on perfect for what it should be… (normal operating range for a 60 watt laser is 18-22mA… with the lower values leading to a longer tube life… but also lower power available to cut.)


That’s awesome! So glad you were able to fix it. Should we buy a spare now or is there a shelf life issue with having a spare tube?

I wouldn't worry about it... The tube that we have is in great shape... I'd let someone else worry about storing it... We can get a replacement at any time we need to from LightObjects and they have nice fast shipping.