Tell Me About Fusion Welding

May 1, 2019 | By Staff

Question:

What is fusion welding? I’ve never heard of it. Is it MIG, TIG, torch or some other type of welding?

Answer:

Fusion welding is what they start you out doing when you study welding at a trade school. You use an acetylene torch, and you fuse small steel coupons together using no welding rod at all. It is quite possible, especially with sheet metal, to weld it together with no rod. You merely place the parts together with a slight gap between them, and then puddle them together with the torch. You are ready to go on to bigger and better things once you can do this task with good penetration, no holes, and little to no warping.

It sounds easy, but it takes a while to get the hang of it. At first you usually make pools of molten metal, and after that you warp the coupons, and make holes from the heat and then, finally, you develop the skill to puddle the molten metal just right so it looks like a stack of dimes that has been knocked over on its side.

Such welds need very little sanding and filling with plastic filler or lead to finish them. The masters can do the job with no fillers needed at all.

According to an old and no doubt apocryphal story, an out-oftowner once asked clarinet master Benny Goodman “How do you get to Carnegie Hall?” Goodman’s oftrepeated reply was, “Practice man, practice.” The same applies to fusion welding. It’s definitely not something you can do right away, but it can make the most beautiful patches imaginable.