Everyone's 2 cents is flying so here's mine. I have welded leaf springs and was told it can't be done. The 68 Camaro I welded lasted me 15 years and put 80,000 miles on it,then I sold it. I have patched many tubes with no problems. Back when the tire's were not steel belted I use to count the rings on my worn out tires on my car and after three separate cords where showing I would then remove the tire. The tire would resemble an inner tube at that point, I did however have the occasional ultra quick flat when I pushed the tire to those limits, you could hear the air escaping at as you drove down the road. Not recommended for the faint of heart.