I'm working on some forge projects and I'd like to drill some insulated firebrick. It is very soft, porous material made primary of silica and alumina (see info here). Thus it is abrasive but cracks very easily. I do not need much precision on the holes, but it will be a large number of high aspect-ratio holes. Say about 100 holes, 1/8" diameter, 2.5" deep.
I'm guessing that a masonry bit is the best approach, and that clearing dust out will be key. I will not be doing this on my mill, I'll use a drill press and will have a shop vac running. I was wondering about using some sort of spade bit, even a shop-made one, just because the material is so soft. Any thoughts on best approach? With so many holes, I really want to avoid cracking the brick on my 87th hole or so. I will do some experiments but figure it's worth asking your collective wisdom.
I'm guessing that a masonry bit is the best approach, and that clearing dust out will be key. I will not be doing this on my mill, I'll use a drill press and will have a shop vac running. I was wondering about using some sort of spade bit, even a shop-made one, just because the material is so soft. Any thoughts on best approach? With so many holes, I really want to avoid cracking the brick on my 87th hole or so. I will do some experiments but figure it's worth asking your collective wisdom.