Hi all,  Just to add to the "brazing is as good or better than" string,
I had a differential repaired on my then brand new 1982 3/4 ton Chevy
truck by a Chevy dealer in Illinois, because it had a crack in the
differential casing.  They brazed it.  When I traded it in (with
185,000 mi.), in October of '98, the braze was still good, no breaks,
no leaks.

I've also seen one brazed piano plate that was working well after 50
years.  The rest of the piano was junk from being dropped in moves,
but the plate was good.

When I was in the Navy, though, the only permanent cast iron repairs
were made by oven heating the valve bodies of large valves, or pump
casings, welding them with a rod at the proper temperatures and
gradually cooling them (using a prescribed time table, logging temps
every 1/2 hour).  Then they were tested with dye penetrant to see if
there were any other cracks or if the weld was not secure.  I never
saw them fail, when done correctly.  (We put temps from 60 deg F to
950 deg F and pressures from 0 to 1275 psi through them.)

Moral of the story: Make sure you've got a good, competent welder
(as in all repairs) : ).

Well, enough of that, back to work on the Wurlitzer band organ...

Dan Armstrong
Armstrong Piano Tuning & Repair
Pine River, MN