Fire in the hole!!!

[Rick Hubbard]

Here’s a first for me. I wonder if anyone else has had this happen:

This week-end I was using my router table to make some 45 degree lock miter joints and I came up with a really cool jig for holding the vertical stock. The problem was, however, that one of the screws holding the jig together came in contact with the bit.

First there were sparks (lots of sparks), then there was smoke (but just a little smoke). I shut the router off as soon as I could believe what I was seeing and started to investigate the problem. Then I realized that even though the router was off, there was smoke (LOTS of smoke) coming from inside the router motor. The bloody thing had a nice little blaze going inside it!

Rather than grabbing a fire extinguisher, I tried blowing the fire out with my breath. That didn’t work, so I grabbed my air hose and blasted away. That seemed to work, then it hit me that my DC was still running so I raced out side to the DC bag and pulled it out of its frame. I couldn’t tell if there was fire in it or not because of all the dust, but just to be safe I turned it upside down and emptied the contents onto a snow-bank.

After all this, I decided to hang out in the shop until midnight that night just in case there were some live embers still hanging out in the ductwork. The shop and the garage and the house are still standing, so I guess the immediate danger is past!

Rick:o

[Chris Tsutsui]

So what were the casualties?

Does the router still work?

Can the router bit still be used? heh probably not.

There's an invention idea... How about some type of smoke detector built into a dust collector so an alarm goes off if something is smoking.

[Eric Gustafson]

So what were the casualties?
There's an invention idea... How about some type of smoke detector built into a dust collector so an alarm goes off if something is smoking.

That is a darn good idea. I am going to put a smoke detector in my dust collection closet as soon as possible.

[Chris Konikowski]

Good learning experience. From the sounds of it, the router was never on fire, it was smoke comming out of the dust collector port?

As an aside, we had a house fire where the person was smoking on the patio before work. The fire didn't start rolling until some time that afternoon. Looks like the cigarette caught some embers that HOURS later finally decided to burst into flames. It can happen a LONG time after you think something is out...

Glad to hear everything is OK.

[Rick Hubbard]

So what were the casualties?



No real casualties as near as I can tell but I suppose the $75.00 bit is toast. I started the router later in the evening and it seems OK, but since I haven't reassembled the DC bag, I haven't tried to actually use it with a bit.

So far the worst of it is the terrbile mess I have outside by the DC bag house. The bag was pretty full. I'm hoping for a big windstorm in the next day or two :) . That should save me some time!!!

In a way, if this had to happen, the timing was OK. Rockler just sent me a replacement unit for my Benchdog Prolift that I need to swap out anyway (more about THAT debacle after I take some pictures to help explain the reason for the replacement in the first place). It is quite a story.

Rick

[Rob Young]

That is a darn good idea. I am going to put a smoke detector in my dust collection closet as soon as possible.

Some (but not all) smoke detectors also include an airborne particulate sensor as part of the detection scheme. The dust can set it off.

[Eric Gustafson]

Some (but not all) smoke detectors also include an airborne particulate sensor as part of the detection scheme. The dust can set it off.

Good point. I wonder how many SMCers have smoke detectors in their shop and if sawdust sets them off??

[Matt Meiser]

My alarm monitoring company wouldn't allow me to have smoke detectors in my shop. They would only allow heat detectors due to the dust issue.

[Rod Sheridan]

Good point. I wonder how many SMCers have smoke detectors in their shop and if sawdust sets them off??

I have the standard elcheapo ionization type of detector in my basement shop and the only time I set it off when I was using a branding iron with a propane torch as the heat source.

Air treatment in my shop is an Oneida cyclone.

Regards, Rod.

[Mike Goetzke]

This is ironic - I think some time last week I read the same thing happened to someone on another forum.

[J. Z. Guest]

Yes, I've routed into a screw head in a jig too. I threw the bit out; mine was an inexpensive straight bit. It seemed OK, as I caught it pretty quick, but if I burn a router cut, I don't want to have to wonder if it was due to a dull bit. Carbide tipped bits should be able to handle the comparatively mild steel used in screws without being ruined, but who knows?

Secondly, I highly doubt your router is damanged, unless it was a cheap one. I suspect that sparks from the routing of the screw ignited some of the fine dust inside the router.

I test power tools here at work, and it takes a severe & sustained overload to light up motor windings on a quality tool. Even on a crappy tool, it takes quite a while.

I also don't build jigs with screws any more, tempting as it may be. It isn't worth it. Sometimes I'll use screws to hold it together in the right alignment until the glue dries, but then I take them out.

[Rick Hubbard]

I test power tools here at work, and it takes a severe & sustained overload to light up motor windings on a quality tool. Even on a crappy tool, it takes quite a while.

I also don't build jigs with screws any more, tempting as it may be. It isn't worth it. Sometimes I'll use screws to hold it together in the right alignment until the glue dries, but then I take them out.

The router is a PC 893. I fired it up tonight and it seems to be just fine, so I guess thats something I don't need to worry about. Even as we speak I'm looking at the bit that hit the screw and for the life of me, I can't see anything that looks like a nick in the carbide, but there are defintely signs of scorching on it. I guess all I can do is chuck it up and see what it it does.

I am probably going to join the ranks of folks who don't use steel screws for jigs. From now on its all brass and glue!!

Rick

[Todd Pretty]

Good point. I wonder how many SMCers have smoke detectors in their shop and if sawdust sets them off??


I would look into a heat detector, they shouldn't false alarm from the dust, but I wonder if the sensor would get coated with ultra fine dust and stop working, if it was installed directly in the dust control system????

[Todd Pretty]

Then I realized that even though the router was off, there was smoke (LOTS of smoke) coming from inside the router motor. The bloody thing had a nice little blaze going inside it!

Rick:o


It was likely the fine dust that coats the motor housing, that stuff will hold a spark nicely and combusts very easily



That seemed to work, then it hit me that my DC was still running so I raced out side to the DC bag and pulled it out of its frame. I couldn’t tell if there was fire in it or not because of all the dust, but just to be safe I turned it upside down and emptied the contents onto a snow-bank.

Rick:o

You are probably very lucky that there was no spark or fire in the DC!!!

If there was a spark, even without a fire, by emptying the bag like that, the dust becomes displaced and oxygen enriched, and that can result in one hell of a fire ball! You could have been burned very badly.

My dad was a fireman and during alot of his haz-mat courses that he taught, he would simulate different explosions... a dust fireball was comparable to propane... and it really didn't take too much to set it off. Of course he always had to try the experiments out at home first, to make sure the lessons worked :D (and I think part of it was to teach us to not blow ourselves up)

[Peter Scoma]

I had that happen recently with a corded hitachi and then a little bit with a cordless Dewalt drill. I was mixing floor leveler with an attachment chucked up in my drill which was working hard for sure but seemed to be getting the job done. After a while smoke started coming from the "vents" on the rear of the drill at which point I disconnected it and set it aside, however, the smoke persisted for some time afterward.

PS

[Mark Norman]

good thing the place didn't go up in smoke!! :eek:

And yer OK...Thats what matters really.

[Art Kelly]

http://hackedgadgets.com/2008/10/12/sawdust-cannon-proven-by-mythbusters/

Also, a long time ago I saw Mr. Wizard do this with flour.

Art