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The Staunton, Virginia news reported that a CNC machine caught fire at the Huss and Dalton facility and caused a lot of damage. The machine was running unattended, and passers-by reported smoke coming out of the building. They put the fire out before it destroyed the place, but it sure seems like a good reason not to leave the room when you leave machinery running!

Dave

There must be something to the story? What caused the CNC fire? Was it metal or wood? I mean if metal then I would figure maybe a coolant problem? If wood, maybe feed rate or spindle speed or combination of these? Maybe something happen to the electronics?

Inquiring minds want to know

I had a fire yesterday. The transformer out back on the pole overheated and started spewing flaming oil. It started the fences on fire behind my house and my neighbors in the alley. Then no power for 4+ hours in 100+ heat. That was fun. NOT!

Thanks for the warning and safety advice.

MK

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I'm outside looking in, just farther from the window than most.

There wasn't much in the way of detail available--here's a link to the news story though: http://www.newsleader.com/article/20110810/NEWS01/110810009/Fire-Huss-Dalton-quickly-extinguished?odyssey=mod|newswell|text|Frontpage%20DontMiss|s

Depending on how well their dust collection system works, it wouldn't take much to ignite things.


Dave

Ha...I'd never get anything done.

It could have been magnesium being cut, which is flammable and hard to put out if it gets a start. It's a reasonable bet that if a coolant pump died when cutting magnesium you could get a fire pretty quick. Lots of possibilities though.

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I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic

Yeah, I have to admit that I leave the room too. I have been trying to do something on the other end of the shop when I have a long job running rather than leave the room though...

I doubt they were cutting magnesium or anything other than wood--I think that all of their CNC stuff is wood router based. Sawdust fires are still probably the biggest threat to any wood shop. I'd bet they had some kind of electrical problem. In a previous life as an electronics repairman, I had servo drivers/servos go up in smoke more than once. Do that around some sawdust and you have a problem! Power supplies and servo/stepper drivers are potentially carrying some fairly serious wattage. It doesn't take much of a malfunction to put them into overdrive, allowing them to get very hot. Good reason to isolate your electronics from the environment as much as you can.

Dave

If a clamp or fixture came loose, or the cutter hit something else made of metal it wasn't expecting to (screw?) then the spark thrown off by the impact can certainly light up a machine full of sawdust in a hurry.

DAMHIKT

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Bob Garrish
Former Canonized Purveyor of Fine CNC Luthier Services

Good point. Nothing is really safe around sawdust--I guess that if the dust collection system weren't grounded properly, a good static spark could have done it too. I've gotten the #&^%%$ knocked out of me on dust collection hose static before!

Dave