Applying boiled linseed oil

[Robert Reece]

It's going to be in the 50's here tomorrow, can I apply boiled linseed oil at this temperature? I think the answer is yes, I just don't want to find out the hard way.

[John Keeton]

For what purpose are you applying it? I don't see any harm to be done, but if the purpose is penetration, you may do better by warming it up some. Be sure and do this in a careful manner with a double boiler setup and no flame. I just needs to be heated to about 120* or so - about like hot water from the tap.

It will polymerize on its own and humidity seems to effect that more than the temp in my experience.

[Robert Reece]

I'm applying it as an experiment on some cherry and tiger maple.
The oil and wood will be in my heated shop and then I intend on just moving it outside for the application, so I don't stink up the house.

You think I can heat it in the microwave - although that might defeat the goal of not stinking up the house.

[george wilson]

Definitely do not try heating it up in the microwave !!!!!1 It might burst into a ball of flame.

[craig greene]

Do it inside if you can. I just used some today in the basement on a small clock I made. There really is not much odor to BLO. I would think heating it would cause more odor than just using it out of the can. It was also around 55 here today and rainy, so no outside for me. Inside as well, with climate control, the humidity may not be as much of a concern. My basement was around 65-67. My plan is to wait about 3-4 days then apply lacquer.

[Kevin Begos]

The main thing I find necessary is to cut the first coat at least a bit with mineral spirits.
I would not heat it!

[Floyd Mah]

If you are new to the use of linseed oil, look up spontaneous combustion of linseed oil on the internet. It is capable of spontaneously igniting because it releases heat when drying (as on rags that are wadded up).

[David Thompson 27577]

I'm applying it as an experiment on some cherry and tiger maple.
The oil and wood will be in my heated shop and then I intend on just moving it outside for the application, so I don't stink up the house.

You think I can heat it in the microwave - although that might defeat the goal of not stinking up the house.

Linseed oil, in its pure form (that is, not "boiled") is an edible product. (Note -- DO NOT eat any of the stuff you bought at a hardware store!) It is the oil of flax seeds. Most people I know find that its odor is quite pleasant.

The "boiled" linseed oil probably has not been boiled at all. But it has had chemical driers added to speed the polymerization process. Those chemicals add almost no odor. (And are poisonous)

And IMO, unless you are using it on the very hardest of woods, BLO does not need thinning.

Sooooooo........ I suggest you keep the wood in your basement, and oil it there. This eliminates the need to heat the oil at all.

One last note -- don't use the microwave. If the oil gets too hot, it will probably have a negative effect on the polymerization process.


And as one other mentioned already -- the used rags, brushes, paper towels, etc will spontaneously combust (it happened to me once many years ago). Either wash -- lots of soap, lots of water -- all of those things immediately after use, or get them out of, and away from, your house.

FWIW, I do both.

[george wilson]

I spent several years duplicating old varnish formulae. Linseed oil WILL go off in a BIG ball of fire that rises straight up in the air if it is gotten too hot.

For this reason,I always kept my several explosions OUT OF DOORS when heating linseed oil. There were a few times I HOPED the fire dept. DIDN'T see the black mushroom cloud!!Really,this is true.

[Jim Becker]

You can warm BLO in a water bath. Use a candy thermometer. When I do this, I go to about 135ºF tops. Thos Moser's firm heats their oil before application to about this temperature.

[Prashun Patel]

There are a lot of misconceptions about BLO...

The only real reason to use BLO is for aesthetics or as a varnish retarder.

Since you are using it to enhance the grain, you don't need deep penetration. You don't need to heat or thin the oil. Just wipe it on, and wipe it off within minutes.

There's no reason to do this outside. It's the rags that are the danger - not the fumes from the oil.