Paranoia? Flammable Finishing Rags?

[Eric DeSilva]

After reading the warning labels on some finishing materials, and dreaming about spontaneous combustion of rags and wipes used in the process... I've started dropping the rags in a ziplock with water and throwing them away in the outside garbage. Am I being excessively paranoid? Seems like a waste of ziplocks, but the idea of spontaneous combustion in a shop area with a bunch of nice dry wood seems a little... Worrisome. I've got an exterior door to a concrete stairwell, and one thought I had was to hang a metal paint can with some drain holes punched in it and start sticking the rags in that until they dried. So, am I being anal retentive, or is this a real issue? Do people have better systems? What about just putting stuff in a sealed empty paint can inside?

[Prashun Patel]

Better safe than sorry.

I prefer to leave the rags open in my garage until the solvent evaporates. Small price to pay for a little safety, no?

[Jim Becker]

Yes, you SHOULD be paranoid about this particular thing. Oily rags/finishing rags can cause spontaneously combustion as the oil gives off a lot of heat when it cures. Many of us have actually had scares relative to this.

My disposal method is simple. I have a nail on a post outside away from the shop. I punch the used rag/towel on that nail and let it dry in the breeze. Every once in awhile, they go in the trash cans for final disposal. (And this method doesn't require the waste of a perfectly good ZipLock!)

[Dan Lee]

I usally just hang them out side for a day or 2 until their dry then dispose of them.

[David G Baker]

Eric,
I think it is a real issue. It may never happen in your situation but spontaneous combustion is very real. I use disposable gloves and usually use small cloth rags, when I am finished with the gags I turn the gloves inside out with the rags inside of them. The water in a baggie is a good idea IMHO.
Where I am more careless than I should be is in my metal shop area. I don't use cloth material for wiping the oil off of metal but use paper towels and toss them in a garbage can. A habit I must correct. I actually have a fire control waste can for just this purpose but it is in another building and I never think of it when I am cutting metal.
Never thought of the hang them out to dry method, great idea!

[Dick Adair]

Last summer I was covering my patio with a roof and had stained T&G pine for the ceiling in my garage shop. About 3:30 pm I had finished the 1st coat and threw the wiping rags on top of a plastic trash can lid. Somewhere around 4:30 I went out to check the boards, and the top of the trash can was smoking and had the shop filled with smoke. This made a believer out of me. I now hang them out to dry and do not bring them back inside. After they are dry I discard them. I never thought this could happen this quick.

[Eric DeSilva]

Alright. I'm not being paranoid. The bucket w/drain holes outside seems workable.

[Mark Patoka]

You do need to be cautious with the rags. My uncle's garage caught fire during construction because of a pile of oily rags and my FIL, who is a painter, is also very careful to dry out their stain/paint rags when finished. According to him, there are certain brands of stain that are more prone to igniting than others (sorry, don't know which ones they are).

I just hang mine on a nail to dry or leave them lay outside for a few days and once they are dried and hard I throw them in the trash. You could also get a sealed metal can specifically designed for the disposal of oily rags.

[Lee Koepke]

I have a piece of closetmaid shelving that I hang them on, and my gloves. I am careful to not overlap them and after a day or so they are pretty dry, and away they go.

I even do that with paper towels if I use them to clean up spills on the top, etc.

[Gary Breckenridge]

:mad:Jack London, author of Call of the Wild, was building his dream mansion out of native stone and logs. It was called Wolf House. The last step was doing the interior wood with linseed oil. The workers piled up all the used rags on the wood floor and left for the day. That night... The rock walls are still standing.:mad:

[John Thompson]

I used to hang them on a fence, till one day the wind obviously twisted a couple together in the hot Georgia sun. Scorched the fence and was more of less a fluke as they had been spread properly to dry before disposal.

Just be sure if you hang them you have them pegged down well to avoid what I mentioned. The metal can thingy would work also.

Sarge..

[Rob Bodenschatz]

I'm probably even more paranoid than you guys. I let the rags dry out but even after they dry, I am afraid to put them in my trash can (which is in the garage attached to my house). I put them in the trash when I take it out to the curb. That way, if they do somehow get wet again, the fire will be 200 feet from my house. The question is, am I being overly paranoid or should we assume that once the rags are dry, it's safe?

[Al Willits]

When I was doing body work and painting out of my garage part time I used a metal fire proof container to throw solvent soaked rags in, left the lid open one weekend and came out the next day to smoke coming out of the container, you need to be careful with this stuff.
I now let rags air dry and then into a metal container.

Al...easier than putting out the fire...

[Greg Cole]

Not paranoia to be wary of things that can & do happen. There's been at least one home fire here in the KC Metro area attributed to laquer soaked rags in my time living here.
I'm very cautious to dry mine before filing in the "circular file".

Greg

[glenn bradley]

I lay them out flat to dry if it is just a couple rags. If I will create a number of 'waste' rags, like when using BLO, I have a covered metal bucket that I put a couple inches of water in and toss them in as I go. When I'm done I lay them all out flat to dry and then toss 'em. You are NOT being paranoid and cannot take enough care around flammables and products that heat as they cure.

[John Newell]

Having come this ->||<- close to actual combustion with some linseed oil-soaked cotton rags, I urge you to take this very seriously. I toss them in a sink in the basement filled with water.

[John Williamson]

Just don't keep them bunched up or in a pile after use. It the heat build up has no where to go then you will have some trouble.

[Mike Cutler]

I'm probably even more paranoid than you guys. I let the rags dry out but even after they dry, I am afraid to put them in my trash can (which is in the garage attached to my house). I put them in the trash when I take it out to the curb. That way, if they do somehow get wet again, the fire will be 200 feet from my house. The question is, am I being overly paranoid or should we assume that once the rags are dry, it's safe?

If you are, I am. I do the same thing.
I keep the finishing rags in a flammable storage waste can. They go in the trash when I take the plastic trashcan to the curb at 5am on trash day.

Finishing rags are a serious hazard. Even if they don't combust, there are no guarantees on what sort of chemical reactions can take place.

[Anthony Whitesell]

I don't have a water source my shop, so I have a tomato hoop outside with clothes pins on it. I clip my rags there until they dry, then I toss them.

[Eric DeSilva]

Seems like there is one other lingering question in this thread raised by someone else that I'm now curious about... When rags wet with flammable solvents or compounds dry out, are they then inert? What about if they are rewetted?

My offhand guess is that its the chemical reactions that happen as the material cures that creates heat, so once they are dry, they are in fact inert. Then, unless they are rewetted with a solvent, they are just wet and inert. I'm reminded of when I made a plaster of paris casting of my arm as a kid and was surprised at how hot it got. But, rewetting dried plaster doesn't undo the chemical process that occurred.

However, I'm not a chemist. Anyone know the real answer?

And, while I'm at it, anyone else think its odd that flammable and inflammable seem to mean the same thing?

[Jim Mackell]

Years ago as a member of our local fire dept. we were called to a home with attached 2 story barn for a report of "smell of smoke" in the house. We looked around for awhile and found in the basement level of the barn, a pile of rags that had combusted. The rags had set fire to the boards that had been treated and were leaning against the stone walls to dry. The flames had crept up the boards, burned out a few cobwebs from the beams overhead and then just died out. Not quite enough btu's generated to self sustain.

The homeowner had just spent a few hundred thousand remodeling the place.

[Bill Wyko]

Especially Linseed oil. I saw a story on the news about a guy that went to prison for killing his family. Only to find out a few years later that it was caused by linseed oil soaked rags he had thrown in the garbage that self combusted. What a disaster to endure.

[Nancy Laird]

We ALWAYS put oily rags outside to dry thoroughly before disposing of them. When I was a teen, the house behind us burned because the owner had put some oily rags in the garbage--they combusted and gutted his garage and fire got up into the attic and pretty much torched the house. His oily rags were from changing the oil in his car.

Two ways to dispose: let them dry or drop them in a bucket of water.

Nancy

[Rob Bodenschatz]

Seems like there is one other lingering question in this thread raised by someone else that I'm now curious about... When rags wet with flammable solvents or compounds dry out, are they then inert? What about if they are rewetted?


Yeah, that was me. I would love if someone could answer this.

[Rod Sheridan]

The issue is that the rags are in a pile, and as oils oxidize the heat cannot escape.

You won't have a problem if they are hung up to dry like clothes on a clothes line.

I always dry mine, and throw them away......Rod.

[Brian Brown]

Am I being excessively paranoid?
When it come to fire, I am not sure you can be too paranoid. Fire is not at all forgiving. I once read a story about a recently retired couple who built their dream retirement home complete with all hardwood doors, trim and and crown, then threw the finishing rags into a garbage can in the garage. The next day they arrived to find the home burnt to the ground. Maybe I get the prize for anal retentive here, but I don't want to find out the hard way if a dried rag can spontanioulsy combust. I take the rags, put them in a heavy metal trash can, put a wire grate over the top, put it away from anything that can burn, and put a match to it. If you have a lot of rags, do a few at a time, so they don't explode. The solvents make them burn quickly. By using non-spontanious combustion, I don't worry about spontanious conbustion.

[David Duke]

Seems like there is one other lingering question in this thread raised by someone else that I'm now curious about... When rags wet with flammable solvents or compounds dry out, are they then inert? What about if they are rewetted?



I'm not a chemist either but I would say yes they are inert that is to say won't self ignite and stay that way unless they are re-wet with a flammable solvent.

Since we are telling horror stories about this; around the middle of last year crews were finishing up a 54 unit Best Western motel here locally. The painters had applied a polyurethane finish to the front desk and didn't dispose of their rags properly, just left them laying in a pile where they cleaned the equipment, by 5:00am the next morning the whole place was nothing but ashes except for the stone entry.

[Cliff Rohrabacher]

I toss 'em in an uncovered rubbish can with everything else.

The problem with linseed oil finishes on the rags in a closed container arises because the oxidation causes heat and when trapped it can build to a flash point. Ya need a fair pile of rags to get that. I never have a pile of rags with linseed oil on 'em so it's not a worry.

However when I'm using a flame I make an effort to get the flammables out of the area.

[Matt Meiser]

I either hang mine over the edge of a nearly-empty trash can or spread them out on the floor until dry. Like Rob B., they only go IN the can as I'm taking it out to the road. Either that or if I have a bunch built up from a bigger project and its not too windy, I'll take them all out to our campfire pit and burn them right away.

[Brian Dormer]

I do the water-filled-ziplock-baggie thing. And at the end of the day, those go in a trashbag that gets taken out into the back yard where it sits on a concrete pad - 5 feet from anything combustible.

Never had any smoke - don't want to.

[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. :o:D:D 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/in+your+garage/garage+clean+up/six+gallon+oil+rag+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/product/categoryInfo.web?options.parentCategoryKey=136&index=16&catSearchParams.categoryKey=1690&REQ_SUB_CAT=Oily+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:eek: 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.