Some years ago I got a personal look at the aftermath of an accidental
Spontaneous Combustion fire and soon afterwards I tried a similar set up to see if I could replicate it but I think that I didn’t give it near enough time for the heat to build.

Since then my research indicates a 6 hour time frame is common so I was inspired to try again. In preparation of this effort I bought some boiled linseed oil and a cotton mop head. I also gathered a few combustible cotton rags that provided insulation that is key to the process.

I took a small cardboard box and layed a cotton shirt at the bottom then drizzled some oil over it. Next I layed the cotton mop head on top and thoroughly drizzled oil all over it, both internally and externally. Next I drizzled oil on the rest of the rags that I layed on top, leaving a two inch opening in the center. Finally I lowered the box’s two end flaps over that. This project was conducted outdoors.

Keeping the oil soaked material somewhat bundled allows the heat caused by the drying effect of the boiled linseed oil in to build the temperature enough to ultimately reach ignition.

At 2.5 hours I checked it and felt that it had a slightly elevated warmth. At 3.5 hours it was very warm and I could see some very slight smoke emerging so I grabbed a chair to observe it as it progressed. Occasional breezes would increase the smoke a little more until after 1.5 hours I could not resist blowing on the thick smoke to coax it further. I sputtered and coughed with watery eyes but finally I spotted a small orange ember!

I was excited and could not wait for it to naturally reach full combustion on it’s own so I intervened and fetched a scrap piece of water pipe to use as a blow pipe and was rewarded with a spectacular flame!

This was a proof-of-concept project that made me feel like MacGyver! It would be a very odd circumstance that would require this method to start a fire but now I have it in my bag of tricks if ever needed.