WAG
...which means?
I reckon I am truly the newbie - is it indeed verboten to mend a cracked casting - it must be repaired by discard and replace? (your reference to "published methods")
Beach BrennanPS - Somehow the idea of V-grinding & heli-arcing a crack has a lot more intuitive appeal than keeping the crack with a cute "stop-that-crack" drill hole. I guess I have a fair bit of welded aluminum in my life and quite surprised that it wouldn't "do" in this sort of situation.
