Stacked 1.5" fire bricks for mini forge?

[Hawk45]

I have an old wood buring fireplace from inside the house that is just sitting in my garage. It had about 20 1.5" white fire bricks that were inside. I know the suggested brick size is 2"+, but could I stack them to make them double thick and still be safe?

Thanks,
John
Wannabe Rookie Bladesmith

 

[blindhogg]

Are they soft firebrick or hard firebrick?
Chris

 

[Hawk45]

Not sure of the feel difference of the hard/soft version.. They are hard but not like standard brick hard.. they are white and the composition is a heavy grain. If I hit with a hammer lightly it chips or breaks into many pieces.

 

[AcridSaint]

If it's soft, you should be able to dig a bit out with your thumbnail or a spoon.

 

[12345678910]

Those fireplace bricks will handle some heat, but are not very insulative..
(you will never reach the temp you want.)

You are looking for these.
http://thermalceramics.thomasnet.com/item/low-temp-insulating-firebrick/low-temp-insulating-firebrick-products/023-6003-005-00-02?&seo=110

Any bricklayers in my area didn't know anything about them.

Try the yellow pages in your phone book under pottery supplies

or darren ellis sell them

http://elliscustomknifeworks.hightemptools.com/firebricks.html