Hey everyone, Josh again!

I had an idea for my first forge. Originally, I had planned on using JABOD, with sand as it's 'dirt'. I got to researching a little bit, and read up on Charles' Anatomy and a brief history of side blast forges. Linked here;

I got looking and saw the Viking-style side blast and figured "Hey, I could incorporate this into my JABOD by making the backstop that the Tuyere runs through out of firebrick!" Then, I thought a bit more. "Well, why not just make a dirt base, pack it down, and form a bowl bigger than what I want, and make the entire forging pot out of firebrick with refractory cement between the bricks." The only real issue I see here is the fact that clinker might stick to those bricks and cement between them like flies to... Well, you know the saying. I could easily chisel them off, but I feel like it would give that forge a bit of aesthetics, as well as not having to worry about replacing cracked clay, etc... Cleaning would be fairly simple, and hey, it could be fun to play with firebrick and refractory cement just to see how it'll react inside a coal forge.

I plan on running a length of 2 1/2" schedule 40 piping through the side, about 6 inches from the brim of the firepot, leaving about 2-3" beneath that. I could find some way to shrink the size of that pipe down to 1 3/8" at the tuyere. My plan is to be able to work between 2" and 4" stock. As a beginner, that covers most all the variety of tooling I would like to make, as well as any other smaller sized stock I wanted. Questions, comments, concerns? I'd love to hear them.

-Josh

Semper Fi

Definitely do the firebrick back (as in Charles's Mark III JABOD), but leave the bowl as dirt. Clinker will stick to firebrick, and you'll just be making extra work for yourself.

Also, your planned tuyere is MUCH too big. As a beginner, you're not going to be working anything close to 4" thick, especially if you don't have a power hammer. Go with the 3/4" schedule 40, get started on wall hooks, punches, chisels, etc, and when you have the skill to work something bigger, make a bigger forge then.

3/4” schedual 40 pipe will alow you to work 1” stock (that is a full sized pick head) as this is close to 7/8” id. A 4” tuyere is for forging anvils.

Also, I have successfully forged material a full 2" thick heated in an anthracite fire fed by a 7/8" tuyere. 

This is why I ask you guys! You guys have far more knowledge on the matter than I do. Right, I'll use a 3/4" tuyere made out of schedule 40 pipe. Side blast, with the backstop made out of firebricks. Would you guys use cat litter or sand for the filler? Or just straight up dirt?

Dry cat litter or dirt, as sand is the nasty mother of clinker. Slag is mostly melted silica, (or a dang good lawyer, depending on context). Our British brothers classically use coal ash and cinders, but as you don’t have 4 or 5 forges running to praduce the fill cat litter works ok, and will get beter as ash fills up the voids.