I had a cracked chopper I was going to weld up but there are major challenges to welding a stainless prop. Welding stainless requires shielding gas on both sides of the weld of you get sugaring which is porous and not good at all. Then you have the filler to consider which ought to be a perfect alloy match and it’s hard to know what these props are made from so using 309 ( the stick to anything stainless filler ) is a good choice for unknown alloys but props are critical and having strength variations in the most stressed area of the blade is certainly a risk. Then as mentioned haz and warp from heat and possible hub damage if it’s a rubber hub. Balance etc etc lots of things piling on here working against success.
If if I have things like this? Used or damaged parts that might do the job but might not? I get rid of them so I don’t get tempted to use them. Once their gone, so is their risky potential
but if you had all surfaces 100% shielded and the correct filler and a steam ticketed super pro level welder do the job, then x Ray the welds, then have a prop man balance and set it? It will be as good as a new one for three times the price lol