Originally Posted by Eurostyle
When you cut and weld, in most cases the inside is not painted or fully protected, so yes it will and it does! Unless you are doing a "down to the shell" restoration...
not always no, if you do it right, you prime/paint immediately after you do your initial cut, then you weld your piece in then you again prime/paint.....once you have your rust completely cut out and replaced with new metal. Its virtually as new.
It is rather very inexpensive to do, even on your own...