How long can I keep Canola Oil?

[Col Defender]

My canola oil stays in the ammo can I use for quenching. How long can I keep it there before dumping it out and refilling it?

 

[Ninja Blacksmith]

I have kept mine in a small quench tank for up to a month or two before draining it back into the containers and then reusing it later, so sitting idly shouldn't be an issue that changes it's quality as a quenchant. I'll be checking up on this thread, though, since I have a similar question. I know canola can be used multiple times, but I have heard from many makers that after a while the oil becomes completely useless, I just don't know if the canola oil's uses are limited, or if they mean the shelf life.

 

[Stacy E. Apelt - Bladesmith]

When you can't stand the smell, or when the color gets too dark.

 

[Karl B. Andersen]

Until you run out of french fries!

 

[woodwrkr221]

So long as my cat thinks it tastes good enough to lap it straight out of the quench bucket it should be good enough for knives.

 

[Col Defender]

Well I like these answers! Thanks everyone.

 

[Bill DeShivs]

I have used mine for about 8 years, but I usually only quench springs. I might make a dozen folding knives a year. I understand using it for large pieces will degrade it much sooner.
It stays at room temperature.

 

[GHEzell]

If it is not sealed it can take on moisture, over enough time in a high humidity environment. Oddly enough, this seems to make it a faster quench, judging from the positive sori I got... it can also lead to cracked blades.