# Spontaneous combustion is real!



## clin (Sep 3, 2015)

Yep, spontaneous combustion is real.

Fortunately this was a controlled experiment of sorts. I have been applying Penoifin (rosewood oil base). The instructions warn of disposing of the rags. And there are plenty because you apply it liberally, wait a while and wipe off the excess.

I've been burning them in by backyard grill. Last night I decided to just wad them up tightly and put in the grill, with the lid on. Nothing this morning, but as the grill warmed from the sun, at about noon, my wife said what's burning. Sure enough the wad of paper towels was charring and smoking a lot. I sort of wanted to wait and see it burst into flames. But it was smoking so bad I was afraid someone would call the fire department. So I hit it with the lighter flame. That's all it took for it burst into flame, not unlike using lighter fluid on charcoal.

I knew this was real, but sort of expected nothing to happen. Figuring it requires the moon and stars to align just right. Not the case.

Bottom line is take those warnings very seriously. If I had ignored that, I could have very easily had a fire in the waste can in the shop and possibly had a major house fire.


----------



## wormil (Nov 19, 2011)

So oily paper towels in a heated oven might catch fire, I will be careful of that.


----------



## diverlloyd (Apr 25, 2013)

Yes sir shop rags are dangerous I have a metal trash can designed for just for disposal of rags that have been used for finishing.


----------



## Kirk650 (May 8, 2016)

Early in my woodworking career, I wadded up some rags and paper towels that were wet with wiping varnish and threw them into my garage trash can. Then I took the wife out to eat. Came back, opened the garage door and the garage was full of smoke. No fire yet, but close. I almost burned my house down. I am REAL careful with that sort of thing now. Lesson learned.


----------



## BurlyBob (Mar 13, 2012)

I heard of it and only seen spontaneous combustion in haystacks. I was warned about it early on and now when I'm done with a soaked rag I hang in my chain link fence to dry and then pitch in the garbage.


----------



## Dark_Lightning (Nov 20, 2009)

It's the linseed oil that does it. The thing is, you don't always know if the finish you are using has linseed oil in it. I'm currently applying Minwax fast-drying Polyurethane to a new tool chest, and the directions have a warning about proper disposal to avoid fire. By the way, I am enjoying putting it on, it flows out well and is giving a nice finish (satin).


----------



## clin (Sep 3, 2015)

> It s the linseed oil that does it.
> 
> - Dark_Lightning


There are things besides lineseed oil. In my case it is rosewood oil. I'm going to be wary of anything oily. Most times I just have a few paper towels used for wiping up drips. In those cases, I just lay them on the edge of the trash can and they usually dry by the next day. In this case I probably had half a roll of paper towels. Some pretty well soaked. It takes days for this rosewood oil to dry, and even then it seems to still feel oily, so I still wouldn't trust it.

I'm not a big fan of burning. That smoke smells nasty. But I don't do this very often.


----------



## oldnovice (Mar 7, 2009)

Never doubted that fact.
Saw it in high school and later in my first job.

Buy spontaneous human combustion only happens when someone get extremely angry!


----------



## jwmalone (Jun 23, 2016)

Ive seen it a few times. Its any oil, what happens is oil doesn't dry by evaporation it dry's or cures due to a chemical reaction with oxygen(that's why oils skim over in the can) that generates heat by itself, plus their flammable. Add a little warmth, protect it from moving air(trash can, grill) to pull the heat off, the combustible fumes accumulate, poof up it goes.


----------



## dbray45 (Oct 19, 2010)

All of the curing oils (oils that harden) will do this.
Lindseed oil
tung oil
are some of the worst pecause they are more widely used


----------



## Dark_Lightning (Nov 20, 2009)

> It s the linseed oil that does it.
> 
> - Dark_Lightning
> 
> ...


OK, that's a new one on me, but you are correct. As I was told as a kid, "Just take any oily rags you have and lay them out on the driveway or put them in water or a safe can". I have a wire bin outside the garage that gets any petroleum distillate product soaked item (mostly paper towels from working on the family vehicles) tossed into it until they dries. It works for all my stuff.

I coated a carving I made awhile back with linseed oil, and put the foam brush in water in a plastic bucket. No fire.


----------



## rustfever (May 3, 2009)

Visitors to my shop always ask why I have oily rags laying randomly on the concrete floor. Of course, they are not wadded but laying flat. And they are always several feet apart. And never close to any type of combustible item.

I pick them up and dispose of them properly after they have dried for several day.

Never a problem using this procedure.

Ira


----------



## wormil (Nov 19, 2011)

It's not just oil, for example wet hay or mulch can spontaneously combust.


----------



## martyoc (Nov 21, 2015)

I drape my oily rags over the edge of a garbage can in my shop. The containment - varnish, thinner, or whatever- still produces heat as it oxidizes during the drying process, but all the air around the rag carries the the heat away and prevents keeps the temperature from rising. You can handle the rags during this period and not feel any temperature increase. Usually the rags become stiff and can't be used again. I've been doing this for over 40 years.

Think about the finish you apply to a wood surface. The drying varnish produces heat but because it is in open air, there is no problem.

-Marty O'C


----------



## Quanter50 (Feb 11, 2012)

I witnessed spontaneous combustion occur when I was an early teen. I was helping my dad with walnut trim in the basement. We were applying Watco Danish Oil to the walnut and then wiping it down with rags. When the rags became saturated with the oil and wouldnt absorb anymore, we were piling them on the work bench. It really wasnt a big pile. We took a dinner break and went upstairs. It was about half an hour later when I went back downstaits to get a scoop of dogfood for our dog. I looked over at the bench and saw whisps of smoke coming out of the rag pile. Yup…..spontaneous combustion is real. Everytime I use Watco Danish Oil I think of that day. I also remember the day dad gassed up the push mower with a lit Chesterfield King hanging out the side of his mouth. That's another story.


----------



## BurlyBob (Mar 13, 2012)

Q50, Now that's a story I really want to hear!


----------



## DustyM (May 16, 2016)

This reminds me of a Parks and Rec episode where Ron's shop was nearly condemned by the city, because he was drying his finishing rags by a roaring fire place.


----------



## ThistleDown (Jun 8, 2016)

I belong to the Fredericksburg Woodworkers Guild in Virginia and at this months meeting a fellow brought in a heap of plastic and metal that used to be a screw and small parts bin. He had been using linseed oil on a project and took a break. His garage, and all of his tools are now gone. No one is dead but think about the pain and expense of dealing with this. Not all insurance includes expensive tools. This is real and happens all the time. Be aware of it and then you only have to read about it and not live it.


----------



## runswithscissors (Nov 8, 2012)

A friend of mine was oiling the teak interior on his big sailboat, and left the rags in a pile. Scorched the beautiful woodwork and required some expensive repair. And he knew better . . .


----------

