Not Engraving
1st timer using LB with my CO2 laser - i just installed new mirrors and finished aligning/ everything seems to be working - hitting Center on the mirrors. When I hit pulse it is coming out in the middle of the nozzle. I hook my laptop to the laser - it recognizes it - I pull up a file and try to run it - it runs but it is not engraving - I have the distance correct I believe- any idea what could be the problem? Thanks
If you have these three – they work
Is Lightburn new or are you a 1st timer with both? Clearly isn’t a new machine or you wouldn’t need to install new mirrors. I’ve run the crap out of mine, on second tube and I’ve never replaced a mirror…
If what you say is true, I’d suggest you do a ramp test to ensure focus.
If it’s coming out of the middle of the nozzle, it about has to be focus.
Thanks -first time user and first test with lightburn. I tried a ramp test that’s when I found out it wasn’t working. I just replaced and aligned the mirrors - one was cracked so I thought I would replace all - tube issues I don’t think so - but how do I check? Any tips are appreciated- I finally figured out how to get my pulse button working after 2 weeks - such a leaning experience.
Thanks
How was that, didn’t press it?
I’m asking as Trocen controller are a bit different from Ruida…
You can check your tube for proper TEM00 resonance or mode.
Hi -I think you were helping me on Reddit with checking the connectors lol. I finally figured out that I needed to clear the files from the controller before the pulse button would work - it can have nothing on it. Thanks I will check out the link- I really hope it’s not the tube - what an experience lol
Interesting… I’ve had strange things happen with the Ruida memory being full, but I’d never connect a failing button to full memory.
Ditto, but if you want it to work properly, it’s a good idea when you check the M1 placement of the beam from the tube, to just check the TEM mode also.
These tubes are pretty tough, even though many claim they are fragile… It’s likely OK, but it’s smart to check. If it’s not in TEM00 mode, it will never align properly.
Ok thanks- I will keep you posted
So I want to test mirror 1 with a pulse - 15% is adequate? Thanks
If you look at the graphic in the link… The perfect power distribution (Gaussian power distribution) is that most of the power is in the center and there is less the further away from the center.
To be able to see this in your pulse, it has to be very light touch. If you burn a hole through it you can’t tell anything…
I don’t know your machine… with a Ruida, you can go into the console and set max power along with pulse duration… I set mine to 1mS, if I have to I pulse it more than once.
You will have to hunt around to find the correct value… If you can see the variation of power across the spot, that’s what we want.
Ok thanks-I will post a pic tomorrow when I do this
So here are the pics from this morning - please let me know what you think I believe it’s out of TEM00 mode? Does that mean I need a new tube? How difficult is it to replace it? I have another pic of mirror 1 - it didn’t burn thru the tape - just wonder what the difference is?
I spoke with a laser tech in my area and sent this pic to him - he said it definitely needs to be replaced- can someone tell me if I can test anything- just want to make sure he’s not just trying to get a sale - thanks
Your output, both he and I agree you need a new tube…
Good luck
Thank you - can you tell me how you can tell from the pic of the beam?
This tells all
The mark left should be round, dark in the center and less power as it moves towards it’s outer area. All of this power is distributed like a doughnut, all the power is around the edges… At least most of it, some is just missing, like the top
Exactly as I advised in post #9.
I don’t know what else you want us to do … It’s clearly a tube failure.
Posting more questions about this is useless as you can’t change this externally the tube has gone out of resonance.
Thanks- no more questions - got it
Start with basics, Do you have speed and power set correctly?
You’re not the only one in a boat of users where the tube has failed.
Nobody want’s the expense and downtime, not to mention potential alignment issues.
It’s especially true when you get a new machine and the new tube will not maintain a TEM00 mode…
Sorry about your loss, it’s also happened to me… My tube went out over a three day weekend… Fine on Friday, terrible on Tuesday… This is the target.
Previously, the impact point was dead center. I replaced the tube 
Some people have gotten great life out of the tube, some haven’t… It’s refereed to as a consumable … the term is probably or somehow related.
I don’t think I got the life I should have from mine, so I also fit into the looser group when it comes to replacing tubes.
Change out the tube, it’s not too tough, just don’t change the tube diameter unless you want to open a large can of worms. The changes the complete optical path.
This isn’t too tough… I used HV connectors from Amazon – they are also reusable only using a set screw for the hv connection.
The anode or negative/ground return path was a wire that I had to splice, you can see the red shrink tube I used on it.
@Fred the problem is the tube – that makes it not possible to align the optics properly.
Thanks just very frustrated because I haven’t even got to try the laser - it was used (I guess buyer beware) - the previous owner did show me it working but I guess when I moved it home I damaged something? I was told it had barely any use. So I measured the tube - I come up with 1232mm long and 55mm wide - any idea on the watts? The previous owner didn’t know too much about it . Thanks everyone
