Hi Jock
On (27 Aug 97) Jock Rogan wrote to All...
 JR> I recently managed to obtain an old cast iron kettle that must be about
 JR> 100 years old.
 JR> Now I want this to sit on my wood stove and keep water hot for my 
offee.
 JR> Trouble is is seems to rust as it boils. It seems to need sealing of 
ome
 JR> sort.
Why is the rust a problem?
a. are you concerned that the brown beverage is unhealthy? If the kettle is
clean then no health risk. If it is an irritation, I mean a worry, then you
might dangle an inner vessel of stainless steel filled with drinking water
and use the outer brown water jacket as a heat source.
b. if you fear that the kettle may corrode due to rust coming away, not a
problem. Cast iron is very durable, should last for hundreds of years in
kitchen service. Things tend to break not corrode.
Sealing is a danger 'cos the sealant might poison you. If the sealant is
electrolyic ie polar then accelerated corrosion due to electrolysis might
result. An immersed zinc or magnesium block resting on the base might stop 
he
rusting [cathodic protection] but then you would have to ingest the 
onsequent
salts generated as the "noble" metal does its job. If you suffer from
indigestion or stomach ulcers this might suit you fine!! but unsupervised
medication carries risks.
My comments are valid for some other HOMEPOWER water management strategies.
  Cheers.....ALEC
... Me drive? I'll take the train as the good Lord intended!  ^oo   oo^oo   
oo^
--- PPoint 1.92
---------------