Despite all the science going on here..., I don't think there's much to spoil. This is a very solid body part. Try to carefully fix what you can. At the point where it will no longer be possible, cut it open, thereby releasing the tension, and after adding material, weld again.
Think of the person who was the first to do it..... it is impossible to translate what I think..... not all who do crafts are good craftsmen.