Laser losing power

[rgall0]

I've had a problem with my laser losing power over the last week. I normally cut 1/8 acrylic two pass 400 ppi at 11 ipm and get a clean cut but now I'm at 6 ipm and not all pieces cut clean through. I cut at 60% power which on my machine is 15ma and the meter shows no drop in power while it's cutting but the laser does get weaker as it cuts. I tried tuning off ppi and slowing it down to 5 ipm but it still is not cutting like it should through 1/8 acrylic which I use to cut at 7 ipm without ppi.

I bought a new power supply from lightobject which is in the mail. I figured it had to be the PS because I bought the tube from lightobject in first week of July 2013 and only use the machine an hour a day and never over 15ma. I even set the max power in lasercad dsp config to never go above 18ma. I know it's not the water temp because I have a 350w chiller and the water never goes above 72F and I also have a water switch so the tube can't fire unless there is water circulating. I just test fired the laser while watching the tube and it has a whitish glow. Does that mean the tube is dying from so little use. The tube is the 850mm one so I cut a hole in the end and made a steel box to protect the tube and block light leaking.

Mirrors are all perfectly aligned and the lens is clean.

[Tech_Marco]

Have you checked the aligment? Also, did you clean the focus lens? If there is miss alignment or dirted on the focus lens, it will cause power drop tremendously.
Was you work shop very cold or at room temperature?

If you could do 1/8" (3.2mm) at 5mm/s (4.65mm/s) with low PPI and 15mA, the tube was performaing an outstanding job. I doubt it that was caused by the power supply if it could delivery 15mA to 18mA. I think it is either the mirror/lens or the tube

Did you use air-pump by the way?


Marco

[rgall0]

Have you checked the aligment? Also, did you clean the focus lens? If there is miss alignment or dirted on the focus lens, it will cause power drop tremendously.
Was you work shop very cold or at room temperature?

If you could do 1/8" (3.2mm) at 5mm/s (4.65mm/s) with low PPI and 15mA, the tube was performaing an outstanding job. I doubt it that was caused by the power supply if it could delivery 15mA to 18mA. I think it is either the mirror/lens or the tube

Did you use air-pump by the way?


Marco

All mirrors are aligned perfectly and the lens is spotless as I clean it weekly. I have air assist working and the laser is in my home office which is always around 70F. The power drop has been pretty dramatic and every day is a little weaker. It's day and night difference from how it's been cutting since July. Can the tube going bad drop power so fat? I read on the forum that tubes have a shelf life. There are no dates on the tube like the original tube so I'm wondering if I was shipped an old tube maybe?

Today it's cutting 3mm acrylic ppi turned off at 4mm/s single pass which is what I use to cut 5mm acrylic at. A few weeks ago I was cutting 3mm acrylic at 8mm/s single pass. Every day I have to slow it down more and more.

My power supply will be here Monday and I'll know is it's the tube.

[rgall0]

Got the new power supply and it's definitely the tube. I have gone over everything 10 times and always come back to the tube. Mirrors are perfectly alligned and lenses is clean. As job goes on laser gets weaker and weaker. Every day the tube is weaker and today I can't even cut through 1.5mm acrylic with two passes at 8mm/s. I bought the tube from lightobject in July and it has less than 200 hours use. Did I get an old tube or customer return?

[Tech_Marco]

Its unfortunate your tube went out quicker than normal. But I need to make it clear that we DON'T sell used tube!

Remember that most tube manufacturer provide warrant for 3 months while RECI provide 6 months. Usually a tube can perform better than the warranty. We carry the same warranty the tube manufactory who are giving us and we cover the same period to our customers even though we have to cover shipping time (1 month) ourself.

Marco