The power supply on the Full Spectrum Laser died in an unusual way on Tuesday afternoon. It was outputting very little current and sputtering. The power supply has been replaced with one of the three spares ordered from China a few months ago. Carry on!
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How much do these cost?
They are approximately $200 each when imported from China several at a time. If purchased from US sellers they are around $700 (hence keeping a few on hand). For a while the laser committee looked at alternative power supplies but settled on these because all of the others tried had equally bad shortcomings but were even more expensive.
The dying power supply is on the free shelf but donee beware, here be dragons. It’s a high voltage power supply in the tens of thousands of volts range and has some pretty big caps.
If you vacuum the outside up a bit, I can look at it next time I’m in the shop – no guarantees.
If it’s something simple it might be possible to put back in service.
At $200, it’s pretty much a consumable. They have a hard life as soot is conductive. And the laser makes soot. 
Woodshop found this out recently… Don’t cut lasered stuff on the SawStop!
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Like a CRT TV, with giant caps just waiting for their opportunity to kill you?
The electronics in the laser area are typically filled/covered with sawdust as is most everything else in the workshop. The dirtiness could be a factor in the failures but I suspect it’s something else specific to the design of the power supply. If the soot was causing shorts I think there would be a lot more failures in electronics surrounding the laser.
Moving forward I’ll add blowing out the power supply to the list of maintenance when other things are done like cleaning the mirrors and lens, it won’t hurt anything and might improve the longevity of the power supplies.
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Eek! Wonder if we should set up an external fan with HEPA filter and run the computer cases with positive pressure filtered air?
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Thanks for fixing this!
Wood Shop keeping the doors CLOSED, as posted, might go a long way. Is this even covered in Wood Shop Intro to Basics?
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@MathewBusby - this sounds like a pretty important little factoid. Do you think it merits posting in Wood Shop? Not everyone who uses the wood shop lurks on the laser talk forum.
Care to explain this rationale ? How does laser cutting a material make it damaging to a table saw ?
If it’s a dust / soot issue then vacuuming the material before cutting on the table saw might make sense, but how is whatever effect that’s causing the problem generated specifically by the laser ?
Wood that has been laser cut has soot which is more conductive than wood normally would be. This triggers the safety mechanism on the SawStop. I agree that laser cut wood should never go on the SawStop but I don’t think soot is the cause of the power supply failure. The dust and crud in the power supply is brown like saw dust, not black like soot. The power supply likely failed because it’s designed poorly and we’ve never had one last more than six months regardless of cleanliness of the thing.
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The carbon from the scorching of the laser is conductive. It turns out it is conductive enough to trigger the Saw Stops safety feature much like a finger or a hotdog.
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Righto.
This happened recently. Don’t cut lasered materials on the SawStop. In Woodshop Basics, we explain the principles of the SawStop system, but none of us realized that lasered materials would activate it until it happened a few weeks ago.
I can’t say whether this has anything to do with it or not, but the high-voltage components are MUCH more likely to arc over in a conductive-pollution environment than line voltage and especially low-voltage stuff in a computer.
Whether that happened could probably be determined from an inspection of the circuit board.
Although I would suggest that it would be a good idea to mod this stuff so that it is pressurized with filtered air.
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The slow-motion video is quite impressive. Whatever that blade and module cost, it is far less than an amputated finger.
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The module is $70, and it damages the blade. Blade repair, sharpening, and/or replacement can vary.