On Thu, 14 Jul 2011 02:44:57 -0700 (PDT), Matty F
wrote:

I've not seen cast iron welded before. Anything to worry about?

Brazing is often preferred with unknown materials as cracking after
welding is very common.

http://www.twi.co.uk/content/jk25.html has some good articles on the
subject (you need to register for free access).