PSA – Avoided a shop fire today!

[Teak]

I was ripping some face grain plugs from 2x2 scraps of Western Red Cedar on my Craftsman zip code saw today. The piece in question was about 16” long. About 6” inch into the rip, I noticed what looked like smoke rising from the far side of the rip fence (not the blade facing side). I was wearing the elipse low profile dust respirator (from Lee Valley) so could not smell the smoke however, a slow realization dawned on me as I watched the white smoke rise and tried to avoid a kickback that this could be trouble.

By this time, the material was already 12” done so I quickly finished the cut, stopped the saw and removed the material. I could not find any burn marks. As I went around the saw, I saw smoke coming out the dust connection port. I opened the cabinet and sure enough there was more smoke.

Time seems to slow down during such events! I recall staring at that smoke and thinking, I don’t’ have an extinguisher with me so if this thing lights up on me, what am I to do. I quickly realized that the only two things stood between the saw and the garage door. One was my saw horse, which was quickly removed, and the second was my Dewalt miter saw on stand. I reasoned that if the smoke did not stop, I will open the garage door, move the miter saw and move the table saw (on castors) out to the garage pad. If it were to burn, that is where it will happen, not in the garage and the house.

Fortunately, the smoke gradually dissipated and I could not find or see any ambers in the saw dust. I waited almost five minutes before vacuuming the dust from the cabinet using my Oneida dust deputy. Figured it is easy to run out with a dust deputy on fire than a burning table saw! 


I still cannot determine what triggered the smoked unless there was metal embedded in the wood. Regardless I have some questions for the collective brain trust.
1.       How many of you have an extinguisher in the shop?
2.       If one uses the extinguisher on a machine, is it toast (assuming the fire is put off) or can it still be salvaged?
3.       I was lucky that this was in the saw cabinet and quickly spotted. If this was in the dust collector, I would have missed it because it is in its own closet. Although that closet is lined with rock wool insulation (fire proof) what other precautions can one take? Any of you have the unfortunate experience of a dust collector fire? What worked and what will you do different?
4.       Any other words of wisdom or advise to tackle such an emergency?

I also found this on the FWW website http://www.finewoodworking.com/2010/02/02/10-ways-to-avoid-shop-fires. Counting my blessings here. 

[teetomterrific]

Note to self: Buy Fire Extinguishers for my new shop.

Sounds like you were lucky this time. I've never seen anything like you experienced but just hearing about your experience makes me a bit paranoid. I'm especially careful about oily rags and spontaneous combustion, as well as keeping things swept up and as dust free as possible. Since there is no water in my new shop, sprinklers were not an option but I doubt I would have installed them if it were. I'd rather take all the other steps to mitigate the risk of fire. My gas heater I had the contractor install is a Modine HDS enclosed combustion unit for the very reason that fine sawdust can be explosive.

I will say that chances are if whatever was smoldering in the cabinet got sucked up by your dust collector it likely would have been extinguished by the DC airflow.

[lincmercguy]

I think you should have at least one extinguisher in the shop, if not two.  Make sure they're decent size, and that they're for ABC fires.  If you do have to use one, clean the material off of any metal surfaces ASAP afterwards.  You don't want that material on the metal for longer than needed.

[EightFingers]

Maybe a small piece of wood got caught in the works of the saw somewhere and finally fell out.
Good reminder.
I do have a fire extinguisher plus a 2500 gallon water tank just ten feet from the shop.

[iclark]

I still cannot determine what triggered the smoked unless there was metal embedded in the wood. Regardless I have some questions for the collective brain trust.
1.       How many of you have an extinguisher in the shop?
2.       If one uses the extinguisher on a machine, is it toast (assuming the fire is put off) or can it still be salvaged?
3.       I was lucky that this was in the saw cabinet and quickly spotted. If this was in the dust collector, I would have missed it because it is in its own closet. Although that closet is lined with rock wool insulation (fire proof) what other precautions can one take? Any of you have the unfortunate experience of a dust collector fire? What worked and what will you do different?
4.       Any other words of wisdom or advise to tackle such an emergency?

First, thanks for the PSA. I don't have a guess about the source of the smoke unless your blade is dull and you hit some kind of pitch pocket (does that cedar do those?). I assume that the sawdust build up in the cabinet was not enough to be where it could rub on moving parts.
1) I have 3 fire extinguishers in the shop. Each one is medium-sized and next to a doorway. I put them where I could grab one and consider going back to extinguish or out the door. While you are buying extinguishers for the shop, also get one for your kitchen.
2) no, the machine is not toast (beyond any damage from the fire) but do clean as soon as practicable (as pointed out by others) and expect to disassemble and lubricate any moving surfaces. Any bearings that are not sealed should be repacked.
3) any reason to not put a smoke detector in the DC closet? they do make smoke detectors with remote annunciators.
4) my cell phone lives in my pocket when I am working in the shop. There is no way that I can hear it when using power tools but it is there in case I need to call for help.

[barryvabeach]

Thanks for the PSA.  I have a medium sized fire extinguished at the door to the house  ( my brother was in an apartment that had a fire, he had one of the small extinguishers, and said it was spent in what seemed like seconds, so I prefer the medium sized ones)

Smoldering embers and sawdust are a great way to start a fire, so next time, if there is a next time, resist the urge to vacuum anything smoking into a dust collector.  Not only do you have a great source of fuel, the inside of the bags of a dust collector also has a fringe which is probably pretty easy to catch fire and the moving air will likely just heat up the embers and speed up the fire.    

You might want to invest in a heat detector for your dust collector room -  smoke detectors are based on the amount of smoke that obscures the transmission of light, but so does sawdust,  a heat detector won't go off due to sawdust.    This is the one I have https://www.amazon.com/Kidde-HD135F-Fyrn...t+detector

[WilliamHodge]

How do you know that there aren't smoldering materials in your dust collection system right now? It's amazing how long wood will smolder. Ask a fire fighter.
If it were my system, I would get help from the fire department, Next, I would move all the sawdust in the collector and bags away from any buildings, clean out the saw, pipes, impeller, cyclone, etc, and hose down the sawdust.

I keep (5) 10 ABC fire extinguishers in the shop, and have insurance.

[daddo]

I have an extinguisher and a garden hose just outside the shop door.

The problem with a pile of sawdust is once it begins burning and travels "into" the pile, an extinguisher won't do any good. The pile will continue to burn/smolder on the inside so you have to remove the pile to a safe area. Even watering a larger pile may not put it out. Even if sawdust may not burst into flames, it can fill the space with smoke to the point you can't do anything, so act fast.

The best safety rule in a shop is the 30 minute rule. Wait 30 minutes after the last operation before you leave the shop if you have any doubts, especially if you weld or use torches.

[lincmercguy]

"You might want to invest in a heat detector for your dust collector room - smoke detectors are based on the amount of smoke that obscures the transmission of light, but so does sawdust, a heat detector won't go off due to sawdust."

My old house had my shop in the basement with a smoke detector in the room. I never set it off with sawdust alone. I thought smoke detectors detected the ionization of the smoke, but I may be wrong.

[WaterlooMarc]

Note to self clean out table saw cabinet. The dust collection on my year old Grizzly 1023 is so terrible my little girl likes to pull it out from the front of the saw where the handwheel slot is.