I have been using my little K40 laser for about 18months now.
Had some great fun this x-mas creating ormaments and gifts.
But last weekend, I strted having difficulties cutting 3mm plywood. I normaly cut it set at 50 on my pot meter which is about 18mA on the amp guage and at 7mm/s. Used to get good crisp lines. minimal charing.
Had to drop the speed down to 5mm/s to even have a change of getting through. Started to notice a lot of charing around the cut line.
Did some re-alignemt of the mirrors. Stayed the same. Cleaned the mirrors and lens. No change. I had been cutting on/off for about 3 hours. The laser is in a cold room (15°C) and use a 30 liter reservoir of water. No noticable change in water temp.
Tested the light right after the tube (before mirror 1). at low power a nice dot. anything over 10mA the dot get a lot bigger an not really circular any more.
Decided I must have burned the tube, so ordered a new one. Also replaced the lens.
Power is better, but still a lot of charing on the sides of the cut. Engraving still is sharp (low power), but cutting leave a lot of charing.
Any idea’s what could be wrong?
Any help would be greatly appreciated.
new tube focus test lines: at 12 nice and fine line. anything above that, very wide lines (20mm/s speed)
I see he replaced it, I was under the assumption it had been replace and it’s doing this… did I get the timeline off… ?
In my life of fixing this stuff, a ‘new’ replacement is more of a crap shoot than a probably fix, especially with these Chinese parts.
Don’t know how many ‘bad’ ‘new’ parts I’ve gotten…
Seems like the output from the end of the tube is pretty much a confirmation that the tube isn’t resonating properly… All of these ‘burns’ have a low power area in the center… assuming this is the replacement…
What else could you attribute to that transverse state…? lps?
I’ve always been told and found that without TEM0 transverse state, the tube is history…
As always your thoughts are appreciated in this area …
OK, I see your point, the replacement tube might have come resonating in TEM01* (donut mode). Just bad luck. But the seller should replace it if that is indeed the case.
@Tom_Geerts are those examples from your original tube or the replacement?
no worries
I have put in a warranty request with the supplier of the tube (Vevor)
Let’s hope they are willing to replace it
Thanks for your feedback all. I’m learnig new things
