kast o'lite question.

[USANewbie]

How well does kast o'lite insulate? Is it as good as insulating firebrick? Can it be used instead of firebrick or ceramic wool? Will a  55 pound bag insulate a whole forge?

[Frosty]

No, it's not nearly as good an insulator as ceramic blanket or IFB (Insulating Fire Brick) but it is a considerably better insulator than dense castable refractories. 

An aspect that makes it a current favorite is being a high alumina refractory and resistant to borax based welding fluxes. Being as insulating as it is means it heats up faster than dense refractories, saves some on fuel and time. 

If you wanted to use KOL as the only liner in a forge it will work. 55lbs is enough to do so on a pretty large forge but not knowing how large and what shape you wish to make it's not possible to answer your last question yes or no.

Frosty the Lucky.

[USANewbie]

Thanks Frosty. I was wondering if i could cast it in a medium sized, round shaped forge, but if it doesn't insulate as well as wool or insulating brick I'm not sure i would use it for anything other than a forge door 

[Frosty]

It makes an excellent flame face. A layer 3/8" thick and up to 1/2" thick on the floor makes a concrete hard surface that won't scrape and gouge when you push cold steel into it. It's a high alumina 3,000f castable refractory the alumina means it's resistant to borax base welding fluxes that will dissolve standard light fire brick like a sugar cube or Kaowool like cotton candy in hot water. The insulating bubble component in the refractory now only adds some insulation it makes the forge weigh less. 

Once hot, a sprinkle of flux will literally dissolve ceramic blanket like running hot water on cotton candy, soft brick lasts a little longer, maybe a couple sessions. 

Morgan K-26 insulating fire bricks stand up to flux much better but it's not great.

Frosty the Lucky.