Little Epilog overheating?

[Bruce Clumpner]

I'm running a 6-year old epilog 35-watt mini and need to do some volume etching and cutting of 3/16" acrylic. Layed out my first test sheets, using the full bed size of 12x18. Etching ran fine, finishing in about 15 minutes, then it went into cutting mode (speed 4/power100/5Kmhz). Ran another 25 minutes, about 3/4 of the way through the job and shut down...Oops? Didn't reset for at least 1-hour, so I came back in the am and rebooted OK.

Epilog tech was helpful in identifying probable cause of shut-down as power source over-heating. Sounded right as both power supply and tube were hot, but not excessively so. They suggested adding more air flow the area to reduce the problem.

My questions to the Forum:

• Does it sound right that system would overheat after what I think is so short a run? Are my expectations wrong?
• Should I lower power and make 2 passes to reduce power output on system?
• Anyone have suggestions on running air flow into tube area to keep temp down?
• Other ideas are always welcome.

Thanks.

[Mike Null]

Not being an expert on this subject (or any other) I would think that the tech gave you good advice.

If you are operating in a hot garage, for example, it would be even more likely that air flow could be the problem.

Are you using the recommended exhaust set up?

[Nancy Laird]

Are you using air assist while running your acrylic?

You might think about just putting a box fan pointed at the machine for a temporary solution while you figure out a permanent one. You might also check and make sure that your exhaust pipe is clear---if it gets gunked up, it can restrict air flow too.

[Lee DeRaud]

Not being an expert on this subject (or any other) I would think that the tech gave you good advice.

If you are operating in a hot garage, for example, it would be even more likely that air flow could be the problem.

Are you using the recommended exhaust set up?

Do Epilogs run exhaust air through the tube enclosure?!?
I would think the internal exhaust ducting would be designed to keep the smoke/whatever away from the working bits.

[Bruce Clumpner]

It's in the garage, not a shop, but it's not excessively hot out there. I'm running air assist while cutting, but not raster work. My exhaust is one of the bigger harbor freight units, so it's pulling well enough through the cabinet.

Yes the power supply and tube component is separate from the cabinet, and on this model has 4-4" fans to pull air from on top of cabinet inside.

I do have a box fan, and may try that.

[Bill Cunningham]

It would seem strange that it's shutting down after such a short period. I have run jobs that took a LOT longer than that with no problems.. Have you looked at your tube, to make sure the heatsink fins are not holding 6 years of crud? How long is your exhaust pipe, and what is it made of? Is the blower sucking air through it, or blowing air through it? Is it full of crud? Just a few things to check

[Joe Pelonio]

There are fans to cool electronics but the tube (at least on mine) is cooled by the intake air from the front vents that passes through the inside and out the exhaust. Running even that amount of time on speed 4 & 100% power will heat it up. I never had an overheating problem but I have enough suction from the exhaust that small parts are sucked up it, and in hot weather have an A/C in the shop that I keep at 70. I think a stronger exhaust may be needed, and doubt that a box fan would help. With your exhaust running, will a piece of heavy paper placed on the intake vents stay there from the suction?

[James Terry]

I havent yet seen a laser where the exhaust is cooling the tube. It sounds ...cheap.

I have also never seen any laser with sensors in the exhaust to measure temperature, so it really shouldnt matter how hot the table, substrate or exhaust air get, I would think any overheat condition is in the laser itself, most possibly the power supply, not the tube.

I would take the back off and check the tube and power supply for dust, then consider moving more air. If you find that it helps, you can replace the existing fans with better, faster or just more.

An interesting thing to try might be to go ahead and port the laser tube cooling exhaust into the cabinet so that the production blower pulls through it when on. This would probably increase the airflow over the laser I would think since some are doing this out of the box.

Mine too is in the garage and it's been getting 100+ in there daily. If you cannot keep the entire garage cool, you could add a port in the ceiling from the house AC and then connect that toward the laser cooling intake and then open the vent when you are using the laser.

When I need to work on the machine, I will work late at night or early morning and I will leave the house door open so that cool air flows into the garage. I have a large return in the ceiling right in front of the garage door so this works. I have considered adding a vent in there from the house AC for temporary use, but that is against building code regulations and I just havent yet had the need.

To me, a long-use heat intermittent is probably the power supply. Make sure it is clean, getting airflow and you might also try it on 230V(if capable) and see if it works less hard.

Strange that it doesnt throw a special code or something more specific. One negative about keeping sensitive tools like this in the garage is that it gets too extreme in temps out there, both in hot and cold. And more importantly it gets humid. High humidity along with extreme temps can eat the crud out of electronics. I am guessing that your power supply is dying, or perhaps the tube is drawing too much itself for various reasons.

I have seen people upgrade 25W systems with a 35+ tube and never upgrade the power source to properly handle it.

[John Noell]

FWIW - I have run far longer jobs vectoring at 100% power (cutting intricate pieces out of 8mm perspex) with my AC not working and my laser is in a shipping container in the tropics. I've never had any such problem with my mini.

[Bruce Clumpner]

Thanks everyone for the comments on the run time before it shut down...I didn't think I was pushing the limits of operating the machine.

I'll make another long run tonight when it's cooler out and see what happens. I can also place some fans to cool the tube compartment and see what affects. Will advise when I have something else concrete to report.

Thanks again.