high guys: i am building a gas forge for welding damacsus billets. It is about 9 in high and square and about 18 in long. It has an angle iron frame. I will hold it together with threaded rod. My? is this, will expansion of the bricks be a problem? Maybe i should spring load the rods holding it together. I will appericate and info you can give me. Thianks, Leroyk

First off I would not make it so tight that the forge could not expand to some degree. I one time built a welded angle iron frame that contained firebrick when making my first forge. I just made sure it was not so tight, I probably had about 1/8 slop.
Now heres the bad news I could never reach welding heats with the firebrick forge, so I rebuilt it with some round pipe and 2inches of K wool w a satanite wash and now easily reach welding heat. Good luck with your forge.
Chris

I agree. I think you will have much better performance with a pipe shaped chamber and koawool. It contains and reflects the heat much better, and the circular chamber will also give you a more even heat, swirling the flame and avoiding the hot spots you tend to get with a rectangular chamber.
If you want an easy inexpensive to build forge, a bladesmith named Indian George Rabello, has plans posted on his website. The same plans are also on Ellis custom knifeworks website. Darrin Ellis sells pretty much anything you would need to build a great forge. Most of the parts for this forge you can get at the hardware store. The rest you can get from him.http://forgegallery.elliscustomknifeworks.com
I've made two based on Georges plans and they work great. Also they were simple enough even I could build one.
Good luck and happy forging!
Ed