Laser exhaust getting hot

[Randy Walker]

I seem to be having anew issue with my laser. When I start a cutting project the beam is plenty strong and seems to cut as usual. As it proceeds through the project say 5 minutes or so it doesn't appear to be cutting as deep and the exhaust from the cooling fans is getting a bit warm. Another few minutes into the project and the beam is noticeably weaker, clearly not cutting as it did when it first started and the cooling fan exhaust is very warm.
If I stop it and let the exhaust cool down, when I begin cutting again it will go through the same process of the beam getting weaker and the exhaust getting warmer.
The exhaust vent shave always been kept clean and un-obstructed. I don’t know about the inside though as I have never taken the cover off but I only use it in a fairly clean environment (my office).
Is this a sign that my tube is failing or is there possibly some other issue that can be fixed without breaking the bank?
Also I am cutting at 100% power 5% speed 500 dpi. If that maters.
Any help or guidance will be greatly appreciated

Randy Walker

[Tony Lenkic]

On ULS laser it is important to have tube cooling fan working at optimum. Check if there is a built up of dust on foam filter and around the fan.
If fans are in good working condition than it could be that tube is failing and needs to be rebuilt/recharged.
There are less costly companies that will recharge the tube. You don't have to go to ULS but you will be without machine for a week or two.
DPI does not affect cutting process but PPI does ( it effects how frequently laser fires ).

[Bill George]

ULS also has washable foam filters, also offices have dust and paper dust is more a problem. Clean fans, filters and blow out with low pressure air.

[Randy Walker]

Ok. I guess I will spend tomorrow morning figuring out how to get into the laser case and doing some cleaning. Thank you for your help
Tony you mentioned other places to get laser tubes worked on, any chance you could send me some of those contacts. Im sure I will have to get my machine worked on someday.
Just out of curiosity is there any chance that my laser tube could be upgraded from 30 watts to something higher. Sometimes I could really use some more power.

Thanks
Randy Walker

[Tony Lenkic]

Randy,
Some of the members of this forum have reported positive dealings with these two companies:
Evergreen laser Corp in CT and
Potovac laser in Ohio

[Kev Williams]

In 12 years I've never felt anything but 'lukewarm' air exit from my 40w tube's cooling path. I don't do a lot of cutting, but for a time I was cutting sheets of 54 special-shaped name badges at a time, about 11 minutes per sheet at 100% power, several sheets at a stretch, just barely warm air is all that ever came out...

Getting hot air and less power at the same time says to me you have some sort of electric gremlin, like some power somewhere shorting to ground, or some other something that's absorbing electric power that's not getting to the tube and is turning into pure heat energy...

[Dave Gates]

Randy, we had to replace the laser tube exhaust fan a couple years ago on our VLS system. It was still working just not very well which caused similar issues to what you described....start job but after few minutes wasn't cutting out the material, etc...

[Paul Phillips]

Hi Randy, sounds like your tube is giving out, that's how mine have acted in the past when they went bad although thoroughly checking that all fans and filters are good is the right place to start, and I would second Evergreen laser.

[Angela Smith]

I just learned last week there is another foam filter in the back my Universal facing the ground. I cleaned all my known foam filters in the past but not knowing this one existed threw me.

[Randy Walker]

Thank you Angela
I just ran and checked my machine and I do not have a filter or fan facing down. I really do appreciate that you took the time to alert me though. It could have been the one thing that made all of the difference. That's the great thing about this community, people take the time to offer help even when an issue seems to be resolved.
An up date on how my machine is running: I left the rear cover off of the laser compartment and put the filter on with tape. I have been running cut jobs for the last few days and there is no overheating and no loss of power at all.

Thank you to all who helped me resolve this problem.

Randy Walker

[Klaus Madsen]

On ULS laser it is important to have tube cooling fan working at optimum. Check if there is a built up of dust on foam filter and around the fan.
If fans are in good working condition than it could be that tube is failing and needs to be rebuilt/recharged.
There are less costly companies that will recharge the tube. You don't have to go to ULS but you will be without machine for a week or two.
DPI does not affect cutting process but PPI does ( it effects how frequently laser fires ).

So ULS laser's are not using water cooling?

[Tony Lenkic]

Klaus,

All western made machine use metal tubes air cooled.
Trotec now uses Ceramicore tubes (new innovation) also air cooled.