Small tilt furnace |
This is a small tilt furnace I built for doing Aluminum casting. It was a considerable
step up from the original coffee can furnace. I have found that
it works real well for melting larger amounts of scrap. Because of difficulties
involved in aligning the furnace and moulds for pouring it is not as
easy to use as a crucible . |
The body of the furnace was from an old 30lb propane cyclinder with the top cut off,
and a simple angle iron stand made from an old bed frame. |
The pivots are short pieces of 1 1/4" pipe welded to the body. These pivot
in short lengths of 1 1/2" pipe held to the base with u-bolts. |
Since this furnace has no crucible the burner tube is welded to the body near the
top and angled down at a slight angle. I use the very simple side arm type
burner. And to keep the overall size smaller I used several 8" lengths
of 1" pipe and some elbows to bend the burner tube. This also lets me use
the burner as a handel when pouring. |
This type burner is about the easiest to build and what I have continued to use on
my crucible furnace. Only one hole needs to be drilled in the
end plug for the 1/4" pipe nipple used for the gas. This has a cap on
one end with a # 59 hole for the gas and a connection for the gas hose on the other.
There is tapped hole on one side of the plug for a set screw to hold
the gas tube at the right depth. |
There is a short nipple coming off the air intake side of the"T" that I use to connect
a blower hose. I have found that for melting aluminum the blower and
nipple are not needed. I have used it with a blower and was able
to melt a small amount of cast Iron with the furnace. Unfortunatly I had
started with a partial propane tank and it started to run out before I could get
more than trickle to pour into a ingot mould. |
Since this was an experiment to see if the concept would work I did not want to invest
a lot in the furnace. The refractory was a insulating mix of
1 part clay, 1 part sand, and 2 parts pearlite by volume. To form a nice
rounded bottom for the furnace I made a round slip casting of a small bowl from
a 50/50 fireclay, sand mixture. I coated the whole inside of
the furnace with a 1/2" layer of this mixture to add durability and smooth the
surface. |
Well there it is all ready to pour a casting. You notice that I had to add
a small flask as a raiser and make a large pouring basin to help align the furnace
for pouring. For aluminum this results in a rather long drop for
the metal which could affect the strength of the casting. Because of the
alignment problems I use this mostly for melting scrap. For most regular
casting I use a more conventional crucible furnace with the same type burner. |