shroud welding help

[CPLANEDR@cs.com]

I have a front shroud that was stripped by blasting rather heavily and now
the welder is having problems with the welds cracking.  He was using 1100
tig and annealing.  He's going to try 4043.  The repair pieces are from 
another
shroud.  My question is did the blasting which was done aggressively having
an effect here?  Or the wire type?  He's in a area of no metal corrosion.

                            Thank you,  Kris
  
65, BJ8