Here's a video on building a cool little mini forge, via boing
Wayne Goddard, was the first to publish a “one brick forge”, I
modified his design to make a micro furnace for micro melts (micro
meaning 250g of metal). Nice to see it as a video though.
What the video fails to tell you is, “what” fire brick to ask for…
a K26 is good to use (thanks NASA). Any good pottery supply should
have stock or be able to order you a brick or two. They also have
other refractory items available (Kaowool is my favorite).
These bricks are so soft that you can carve them with a teaspoon
(maybe even with a plastic spoon, although I haven’t done that ).
The total setup will “not” be $30, you have to factor in the propane
torch, and the propane cylinder, which is about another $25-$30.
The best approach, I’ve found, is to buy a Bernzomatic JTH-7 hose
torch and a couple of adapters to allow a POL fitting, then you can
use a standard 9 kg BBQ cylinder. These torches and adapters will set
you back about $100, and a bbq cylinder will be about $30, but it
lasts longer than a fat boy propane cylinder, and the setup is
The torch is worth the investment by itself, imo, and it can be used
to power a micro furnace, so double duty.
Personally I wouldn’t bother with the nail grate, it would just act
as a heat sink.