Paranoia? Flammable Finishing Rags?

[Michael Hammers]

This is a dangerous issue. Anyone with a shop that has no automated fire suppression and dealing with petrolium soaked rags should spend the 40+ dollars on something like a Just-rite (or another vendor) oily rag can. They are shaped in such a way they circulate air and to disperse heat and also keep from sparks. If there is a fire they stifle oxygen. Small price to pay verses the cost of a shop.

From the world wide web.......

"Spontaneous ignition occurs when a combustible object is heated to its ignition temperature by a chemical reaction involving the oxygen in the air around us. This “oxidation “ process creates heat that, if not dissipated, will build up until ignition occurs. Generally, this can happen when the materials are left in piles and the heat being generated in the pile cannot be released into the air.
The possibility of spontaneous ignition is great if the surrounding air is also warm and dry. The added heat, say from nearby machinery or a non-insulated steam line, can either pre-heat the material, which in turn sets off the reaction, or can hasten ignition by adding even more heat to the combustible.
It is simple to prevent spontaneous ignition, since oxygen is needed for it to occur. Materials subject to spontaneous ignition should be stored in covered metal containers such as a rag safety can or trashcan. Admittedly the container will contain oxygen at first. However, the oxidation process will use up the reaction and the reaction will stop-fire prevented."

[Ron Bontz]

I too hang my rags to dry. I do not use a bucket with drain holes because that implies the rags are lying on top of each other allowing them to generate heat. Fire needs fuel, heat, and oxygen to react and ignite. Yes? Hanging them out to dissipate any heat is to me the first step in prevention. The second is not throwing them in a can with other "fuels" that can burn. A make shift clothes line , or just lying them out, out side the shop, and a couple of clothes pins works pretty good for me . I don't think there is a whole lot we can do about the oxygen. It makes sense to me as a FF to keep an ABC extinguisher in my shop. And yes I am also paranoid of loosing those tools I have worked so hard for. Not to mention the embarrassment of a FF letting his own shop burn down. It would be tough to live that one down at the FH.

[Pete Simmons]

Very Real DANGER I knew a family that lost the house, The Dad and Two Kids from a couple of rags thrown into a corner.

I sometimes ask visitors to point out something dangerous in the shop. No one ever mentions used rags. I think they are very near the top of the list for dangerous items around the house/shop.

[Dixon Peer]

Nope, not paranoid. Years ago, when my wife and I were first married, she did some house cleaning and one task was oiling the wood furniture with a linseed oil concoction. When she finished, she put the oily rags in a closet under a staircase (bear in mind she was twenty one years old). A few hours later, I noticed a rancid odor, and lucky for us, discovered the rags before they burst into flame.

[Steve Clardy]

I have metal racks in my finish room that holds cab doors and trim.

I just hang the rags on the end of the racks, careful to spread them out to dry.

Once dry, I throw them in my wood stove.

[Murray Roblin]

General question:
I follow the general approach for finishing rags, i.e. oils that polymerize - their drying process generates heat.

It is mentioned above that rags soaked in auto oil will combust. Is this true? In this case, isn't it just a evaporative process? Wouldn't this be true for other solvents (e.g., acetone, kerosene) as well?

[John Durscher]

I put my used finishing rags in a specialized can for oily rags. I got mine at Griots garage - http://www.griotsgarage.com/product/...g+fire+safe.do These safety cans are used in auto shops for oily rags and are designed for this sort of thing.

John

[Nancy Laird]

It is mentioned above that rags soaked in auto oil will combust. Is this true?

Well, Murray, it's true that my neighbor's house sustained about $40k in damage (in 1962!! dollars) when his oily rags from working on his CAR combusted and burned his house. He wasn't a woodworker; he was an accountant who decided that he was going to save a little money by changing his own oil in his car - which burned up in the burned-out garage.

Nancy

[Steven DeMars]

In my younger days I worked in a print shop on an offset press. This required cleaning the press printing surfaces dozens of times a day . . .

The solvent we used was very flammable. Excellent solution was a metal storage can with a foot operated lid.
http://www.globalindustrial.com/gcs/...ily+Waste+Cans

Steve

[Alison Gray]

I apprenticed "briefly" for a wood finisher/refinisher. We had to lay all the rags out separately to dry for a minimum of 24 hours. Then they could be put in trash bin. And we layed them out on metal racks to be safe. That was not only for products like linseed oil, but for all our staining rags as well. I still follow this practice and then I throw them into a covered metal bin that is not near anything flammable.

[Rich Engelhardt]

Hello,
It's not only solvent soaked rags that can be a problem and combust.
Finishes and the dust created by sanding them can also do it, or so it appears.

Bruce Maki experienced it with some dust created by sanding some Varathane. The dust inside the dust collector of his ROS began to spontaneously combust.
I stumbled across his article on hammerzone last spring relating his experience with Varathane he was using to refinish a floor.
Very sobering.