Replacing the two thermistor surge suppressors in the high voltage power supply seems to have cured the laser of its problems. Hurray! It’s actually cutting a bit better than it has been doing recently.

Total parts cost: $6.66, plus shipping. Not bad!

Laser classes on April 3 and April 10 will go ahead as scheduled. A new class or two will be scheduled soon, with people from the canceled March 26 class having first shot.

After a couple of rounds of back and forth with tech support, they had me open up the high voltage power supply and inspect for visible damage. Somewhat to my surprise, I found some. These two big black ceramic disks are clearly blown up. By the part number MF72-5D20 these are power NTC thermistors used as surge protection. According to tech support, this type of failure is usually caused by a random power surge.

I have replacement parts on order (they’re cheap) and will try simply swapping out the thermistors as soon as they come in. If that doesn’t solve the problem I will probably have to send the power supply in for repair ($100 plus shipping and handling). Cost-wise, this could have been a lot worse.

The laser is currently not working at all. The laser tube just won’t fire. I strongly suspect a failed high voltage power supply. I have a support ticket open with Full Spectrum Laser and expect to hear back by Monday. If I’m right about the problem, the downtime will depend on whether they have a replacement power supply in stock.

The laser class for Saturday, March 26 (later today) is CANCELED. We can’t have a laser class without a working laser. The classes for April 3 and April 10 are still on, for the time being, but are at risk of being canceled if I’m not able to get the laser repaired in time.