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Glenn Ashmore
 
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Default Bathtub Crucible

What works against a wood fire is that it takes a pretty big fire and you
can't control the air so it waste a lot of heat. Melting a couple of tons
of lead is hot enough and skimming the dross without melting yourself can be
a real challenge.

The old guys casting ballast would rig a big iron pot beside the mold and
build a fire under it. When the pot was ready they knocked out a plug and
let her rip. That is fine for simple ballast but if you are casting a fin
you need to remove the dross to prevent weakening inclusions and more
control over the pour which means you have to get close to the pot.. I
would not have attempted my pour with a wood fire.

--
Glenn Ashmore

I'm building a 45' cutter in strip/composite. Watch my progress (or lack
there of) at: http://www.rutuonline.com
Shameless Commercial Division: http://www.spade-anchor-us.com

"Dave W" wrote in message
...
There is a very good description of the process in BOATBUILDING by Howard
Chapelle. Wood as fuel to melt lead is entirely satisfactory, it has been
used for years. Beware of using concrete blocks to support the tub;
firebrick is much better as suggested above. If you really want to cast a
keel larger than a bathtub can hold, finding a foundry may be a good
(safe) alternative.