On Sat, 11 Dec 2004 15:14:18 GMT, Larry Caldwell
wrote:

===In article , (Rod
===Speed) says...
===
=== I'd weld or solder it myself.
===
===Solder would probably melt back out with a hot fire, but he could braze
===it. Brazing is the traditional way of mending cast iron.


Well I would class it more as the easiest way to patch it back up,
without having to do a lot of prep and preheat and stress relief
afterwards......but brazing is still not anywhere near as welding it
up with the proper rod....but a brazed joint other than being a
different color is actually stronger than the parent material (grey
castiron) itself.......cast iron is approx 40,000 PSI tensile where a
braze with proper rod is in the neighbnorhood of 60 to 70,000.

To me, even if its only to serve a functional use, and aestehetics is
not a concern, I would still probably weld it, as there is just
something about that brass color up against a nice cast iron part for
some reason or other.

I would not say the cast iron is worn out, as much as its a natural
tendency for cast iron to obey the laws of physics, even if you don't
know them. It expands and contracts a geat deal and bing so grainy in
structure its a given it can crack, from excess heat or cold or rapid
temp changes or a shock.

When brazing or fusion welding CI temperature controls the outcome. It
requires preheat if the job is to be done right and last, and a good
bare nickle rod, with an O/A torch, and a slow proper cool down and
stress relief or possible anneal afterwards, even if its brazed this
is still the acepted process.

OH, they make an item that will repair it simply by drilling a few
holes, inserting some type of fastener, and lacing it...I think its
called stitch weld or lock weld and from what I hear from folks if
your not interesed in how it looks its as strong as a properly welded
repair when done properly. Personally I never liked what the stuff
looks like but its still an option, though I have used an embedded key
to repair cracks in cast iron but unless you have machine shop
capability it would be pretty expensive, but it does work and works
great.

Having a pattern made or having a repro cast can be pretty expensive
as well........do you know anyone that has a back yard foundry and can
handle cast iron.......they may be able to do it.
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