Forge Build Pt I


Planning The Forge Build

Hey all! It's been a bit of time since I last wrote. But, with a bit of equipment needing upgrading, it's time to get some more blade talk out there. 

I forge all my knives using a propane forge I built a few years ago, a fairly redneck one but it worked extremely well. Despite this, it's starting to fall apart and there are some things it lacks that I could use.

So, it's time for another forge build. 

This series of articles will cover everything from the bare frame, to insulation, to building the venturi burners. 


The build of a propane forge usually revolves around the main "frame" piece, the steel containment. I like to browse antique stores a lot (it's a bit of an obsession), and on one of my journeys a few months ago, I found an antique fire extinguisher.

Did you know, by the way, that fire extinguishers used to be based off a soda-acid reaction in order to build up pressure? Who knew! Turns out those vinegar and baking soda volcanoes you made as a kid actually had an application. 

I picked it up originally intending to use it for a quench tank, but never put it to that use. Instead, it's the perfect size and shape for a propane forge.

Having a fire extinguisher made into a forge is a bit poetic, don't you think?


The forge will have hinged doors on both ends, the front end (the top of the extinguisher) having a small opening, but with the ability to open wider (see sketched diagram above), and the back end completely closed unless the door is opened. This will allow me to contain more heat, or open the forge for wider projects.

Inside the tank will be ceramic wool (an insulator), coated with a refractory, and layered along the bottom with firebricks.
Assuming I can build it right, I'll have a few torches inserted nearly vertical, but at a slight angle to swirl the flame. This swirl helps the efficiency of the forge as well as contains more heat.

The torches will be simple venturi burners; we'll get to the details later when I begin building them. 

Feet for the forge will be welded or bolted on, and it'll be fixed atop an old barbeque cart, as I like to be able to move the forge around. 



So, there we are.  As far as tools go, forges are actually extremely simple. A propane torch pumps out flame, all you gotta do is build a structure that is shaped so that this heat is most efficiently contained and controlled, and the workpiece supported. Under this basic principle of course, there are a lot of nuances that help work together for an efficient, convenient forge. 

You'll notice that I didn't draw up full blueprints and my plan isn't exactly complete, but that's partially how I work: I like to start with a rough idea of a plan, start following it, and modify as problems or opportunities arise. And if there's one thing I've learned, it's that problems or opportunities always arise. 

Caleb Harris

I’ve always fooled around with tools and hardware, but I think my passion with blades started far back in my childhood: wooden swordfights with the neighborhood kids. I became the neighborhood “blacksmith”, using my grandfather’s tools to hammer little crossguards onto wooden sticks. I always tried to find the best scrap wood: lightest, strongest, trying to get the perfect length and shape for each “customer”. This started my passion with blades.
When I was ten years old, I joined a local rock and gem club, learning stonecutting and cabbing, and through that came to take silversmithing lessons from a local jeweler. It wasn’t until around the age of 13, that I turned my attention to bladesmithing, which has captured my heart. 
 My personal obsession with bladesmithing, as I’m sure you can relate, isn’t just the joy and passion of the making: the musical clang of the hammer on steel, the shower of sparks on the grinder, the whisk of the blade over the sharpening stone, but also of the fulfillment in creating something that is twofold: that of beauty, and that of function. It’s trying to make something that is as much an art piece, as a tool that you can trust your life with. That’s what caught my heart, and the pursuit of that perfect combination still drives me.