alright it's 1:45 and it's 100 degrees and rising i am ball milling magnesium outside it is directly in the suns path. i put a cardboard box over it and a big towel. what are the chances of it overheating and igniting? this is a commercial rock tumbler mind you. how long should i mill it before i open the jar and air it out? i don't need another accident.

i milled my BP for 4 hours or so. But i also did it inside the garage and it was nice and cold. I wouldn't risk it. the cardboard would work at a heat insulator and cook it

I dont think there would be any risk. Just in case, put it in a box with a damp towl wrapped around it. I forgot what it is called, but I know from experience it can cool the inside of the box 15 degrees cooler than the outside of the box.

There is pretty much no way that it is going to ignite due to temperature. Magnesium melts at around 1200F and ignites about 50F above that, so there is no way it will get that hot from the sun. I'd be more worried about the motor overheating and some how causing a fire, or just ruining your motor, than ever the magnesium catching fire. I've never ball milled magnesium, but I bet it is safe to probably do it in your house, bring the container outside before you open it, and just air it out there.

quote:

Magnesium melts at around 1200F and ignites about 50F above that

Magnesium shavings will easily light from the sparks created by flint, so it is nowhere near 1250F.

My 2000th post!

(actually my 4225 post )

Yeah, I looked it up and it depends on how dry the air is. In completely dry air it is around 1250, but with more moisture it gets lower, down to about 850. Just incase a fire starts, don't throw water on it. The magnesium will take oxygen right out of the water and leave hydrogen, which can cause an explosion. Just keep a bucket of dirt or sand nearby incase it does go up.

[This message has been edited by creepinghorseman (edited 07-24-2003).]

quote:Originally posted by creepinghorseman:

I'd be more worried about the motor overheating and some how causing a fire,

Thoughts of zero come into the air,

Surface area plays a big role in the tempature of igntion...

~H

what happened to zero?

http://www.totse.com/bbs/Archives/Archive-000007/HTML/20030312-19-002625.html