Hello, I have a universal laser 50 watt air cooled metal tube and it cuts great for the first minute or so and then slowly loses power to a point where it barely etches the surface.

I am trying to cut 1/4 black acrylic

I can set the power to 45% 0.2 speed and 500 ppi and it may cut for 4-5 inches,

I can set the power to 100% 0.4 speed and 500 ppi and it may cut for 2 inches before losing power.

Is this a heating issue? Is this a power supply faulty component issue?

Mind you, when I am cutting I cutting constantly, one complete path.

Temp here in alabama is 85F in my garage.

Any ideas? I am about to get an a/c unit and aim it at the inlet fans if this may help.

The tube has never been changed, but I don't think its the tube, if it were, then why would it cut better when its colder? I.E. early morning, sitting all night cooling down.

I do notice that when I run it at 100 percent the exhaust fan outlet gets kinda warm.

No the screens are not clogged, and yes all fans are working. Z axis is parallel. 2.0 lens, 2.0 offset from workpiece 48 Volts at the tube....

And it does not only start to happen in one area, it cuts anywhere on the table for a 1 min or so the starts to lose power (I thought it was an alignment issue, its not, re-aligned mirrors many times still no luck)

I am stuck!!!(chair)