My name is Joe Marsh (AKA-Narrow Path, Florence, SC) I am relatively new to the heating and beating scene. Last fall I got my first forge, a Champion blower with a cast iron bowl approx. 24" dia. I was advised by a friend to line the base of the bowl with fire clay in order to build up the bottom to the level of the tuyere. This will also provide protection for the bowl. I came across a bag of medium duty fire clay (powder form) which is for temps of 1400F to 2200F. However, when the guy gave me the bag he said I should need to mix with silica sand / cement morter. My question is what kind of ratio I should use. Any ideas?