Vulcanizing

Pardon my ignorance but I am curious about vulcanizing tires. What is the process and the expected outcome?

They grind out the cut, fill will uncured rubber then cook it. When done, a big boot patch is put on the inside. have had 2 tires fixed like this. In time the rubber fill will weather and crack. I think its worth doing if the tire is in good shape otherwise.

The outcome is directly related to the experience and skill of the vulcanizer, whether their business (if not a one-man or family shop) lets them apply it correctly, and they should have the freedom to sometimes say the tire in question should be discarded or limited to low-stress use.

A tire is a composite air supported structure made from high strength wraps of fiber/fabric/wire/rope/cord. And made air tight and given traction with different layers of various types of rubber.
The entire deal is sealed together with heat and adheres together like hot glue.
If the rest of the tire is sound,the damage is limited to a low stressed area and depending on the size of the damage. The damaged area can be ground out, sometimes stitched and refilled with rubber. Then baked under heat with pressure and hope for the best.
Excessive high temps from friction caused by too low inflation pressure,too high speed, too heavy loads & hot pavement over and extended distance. Will heat a tire enough it "unglues" and comes apart.
Pretty much explains the Firestone Ford Exploder adventure.

Cut spot is ut out acording to the dammage with each layer of cords being removed farther back than the previous layer, (Like stair steps) then new cords are placed in with a rubber layer in between each layer of cords untill all layers are replaced. I have the directions here someplace in a shop manual published in 1941. Never read all of the directions.

Another term for vulcanizing is 'section repair'. Tire shops that do this repair use commercially available 'sections'; pieces of rubber with cords already molded into them and cured. A 'section' that has the thickness and number of plies to best work with the construction of the particular tire they are repairing is selected. A concave area is ground out around the damaged spot on the inside and outside of the tire. The 'section' is ground, making a convex area on the surface to fit the concave area on the inside of the tire. Raw rubber is placed in between, and the 'section' is anchored to the tire. On the outside of the tire, the hole and the concave area is filled with raw rubber, building it up higher than the level of the tread around it. All of this is 'cooked' (heated) until it is cured. The outside is ground and/or grooved to match the rest of the tread. Due to the heat and friction generated in highway-speed tires, this procedure is better for off-road applications such as construction and agriculture. My description here is a layman's viewpoint. For more info, use a search engine such as Google and search for '"section repair" tires'.