I've been wanting to build a new forge for several years. I finally got around to it, then forgot to show it off, so here it is:
It's roughly 2ft by 2ft by 18in tall, plus the legs. The walls are 410 that I welded together, and the legs are riveted to the walls. My apprentice (who is a better welder than I am) welded the cuff at the top and around the base of the lid. That protects us and the duraboard from abrasion. The inside is lined with fiberfrax duraboard, which (with some lung protection) can be cut on a regular table saw. So this can get just as hot as the old forge, but without anywhere near the mess or airborne particulates of Kaowool.