This was produced at 20% power it’s an 80w reci tube.
I basically started a new job, nothing changed and it looked super blown out of focus. But everything was fine. So I redid the alignment as it looked wrong but hadn’t been messed with for a while and it was working fine so was suspicious.
Then I got it aligned and during the engraving it got thicker and thin like it was going in and out of focus
Been laser engraving for 5 years but never seen it have almost like a splatter effect at the laser source?
Tubes about 1.5 years old. Also noticed some browning around the coil. Only ever run at about 70% power max when cutting.
It can be measured with a multimeter, but I can’t give you any useful guidance. @ednisley and/or @jkwil are better sources of knowledge for that.
However, I personally would buy a new set of tubes and supply, after 5 years I would think that the investment/maintenance can be justified.
Lifetime is (generally) measured in power-on hours, rather than calendar time, and a laser tube used in production can wear out surprisingly quickly. Six hours a day and five days a week is 1500 hours a year, with tube lifetimes of a few thousand hours (depending on who you believe).
Anecdotal evidence is all we have around here, but apparently laser tube lifetime can be anywhere from “dead in the shipping carton” to “forever”, regardless of how much tender loving care they get.
The scorch definitely looks gnarly. IMO the power supply does not affect the tube’s optical resonance, so … it’s the tube.
Edit: Even nominally reputable suppliers carefully exclude their Amazon / eBay / whatever outlets from the warranty offered on their Offical Sites, which suggests they carefully manage their costs for each channel. I’d be totally unsurprised to learn “Genuine Reci” tubes from, say, Amazon come from the left end of the quality bins.
So mantech think it’s either the tube or power supply. What is strange is that it almost looked like it wasn’t engraving at first so low power then it looked like it was out of alignment.
Really hard to work out if it’s the tube or the power supply but it’s not making any weird sounds or arcing inside the tube…
The nominal TEM00 resonance mode distributes the power as a nice Gaussian hump in the center of the beam, so the focused spot is symmetric with a very high power density in the middle.
All the other resonance modes distribute the power peaks away from the center, so the beam does not focus into a concentrated hot spot.
Great chart… I can see that if I have a problem with resonance, the nice dot will look scrambled like the other views of the chart? Ok… got that. Nice info.
The tube has mirrors at each end and, if they’re in perfect condition and perfectly aligned and the electrodes are perfectly shaped, the HV discharge along the length of the tube will produce infrared light that will bounce between the mirrors with that lovely TEM00 energy distribution.
If anything isn’t quite right, the light bounces oddly and a new tube is on order.
