might think making a sturdy, reliable smelting furnace
to be an expensive affair, requiring financial help
from someone like justmilitaryloans.com,
but that's not the case at all! With a little research,
a lot of creativity and a trip or two to Home Depot,
you can save the military loans for something else
and build your own furnace for very little money.
Here's how I created my "new and improved"
a fair bit of help
from Lionel Oliver's book - "The flowerpot crucible
furnace", I went about scrounging for materials
In the end, an old paint tin was finally put to good
use after having its insides hosed with high pressure
water, and then sliced through with an angle grinder.
The flowerpot shown fits perfectly in the sawn off
to be used for the furnace
A messy tabletop
full of random tools
Two holes are
bored in the "revitalised" paint tin - the
first is for the blower attachment (in order to pump
oxygen through the coals), and the second through
the lid to allow ventilation.
had originally planned to use the old paint tin handle
as the furnace lid handle. However, there was the inherent
risk of the handle being off balance after the lid was
filled with concrete. Thus, the old handle welds were
cut off, and a new handle riveted in place above the
the old handle with a cut off disk
lid is fitted with interwoven thick core steel wire
to help strengthen the cement as it hardens.
is the lid with cement poured in. The cement is jabbed
at rather vigorously to ensure no air bubbles are
left in the mix. The vent hole is formed using a piece
of PVC pipe.
cement in the lid and body of the furnace will be
left for four days (that was the longest I could wait...)
to cure and harden.
lid cement and abusing the air bubbles
a segment of steel tube for the blower pipe
While the concrete
sets, the blower device is constructed. For this,
I utilised an old fume extractor originally designed
for sucking up soldering fumes.
Here, a piece
of steel pipe is being cut to attach the blower to
cement has finally set (maybe), and here is the blower
attached to the furnace via a very "ergonomically"
designed air tube made from random foam cups, pvc
pipe and steel tubing. No personal or military loans
needed here! All together this project might have
cost $25 in materials.
complete with blower attached
A look inside
the furnace with air distributor
Here is a view
of the body of the furnace. I have to admit I totally
ripped off the idea of the air distributor device
(angle iron) from Lionel Oliver's design, but seeing
as I had a right angle shelving bracket leaning right
on the shed, I just couldn't resist.
The air distributor
works well. In the old "dodgy" furnace,
I didn't have this element and as a result only the
charcoal right next to the tuyere hole was heated
small fire was lit in the furnace to test out the blower
and also to finalise the setting of the concrete. Actually
I ended up having so much fun that the "small"
fire turned into one which would consume a whole pile
of backyard junk. So much for reducing greenhouse gasses.
happily crackling up with a small fire
flames rocketing out of the vent hole
The blower works
amazingly well... Intense heat is generated in the
furnace whenever the blower is turned on, whereas
the flames are reduced to mere billowing smoke when
it is off.
I left the PVC
pipe former in place to burn off, which was certainly
easier than hammering it out and risking the integrity
of the furnace lid.