How to solder aluminum with regular tin
Repairing damage to an aluminum car body on your own is very problematic. This is especially true for fractures and cuts, which can only be welded using argon welding. In its absence, such defects can be eliminated by soldering, but the solder does not stick to the aluminum at all due to the instantaneous appearance of an oxide film. However, there is a technology that allows you to solder an aluminum body with tin, avoiding the formation of oxide, thereby achieving a strong connection.
Materials and tools:
- tin;
- gas-burner;
- screwdriver with metal brush attachment;
- pliers or hand clamp;
- wooden block;
- grinder with grinding wheel.
Soldering of aluminum body
The surface of the body around the tear or cut must be perfectly cleaned of paint and oxide film.
After this, you need to tin the soldering area. To do this, pure metal must be heated with a gas burner. Then, under the torch, rub the solder over the hot surface so that it melts. Liquid tin will not stick and will start to roll into balls, this is normal.
Next, the solder is put aside and a screwdriver with a metal brush attachment is taken.
By rotating it at medium speed, you need to scratch the metal without stopping the heating with the burner. The brush will tear off the oxide film that appears when aluminum is heated in air, and the molten tin will be able to immediately adhere to the clean metal before the oxide is formed.
Having lightly tinned the surface, you need to add even more tin on top, then also using a brush to ensure that it sticks along the entire perimeter of the stripped metal. Having tinned the entire soldering area, the required amount of solder is fused on top to cover the damage and the dent around it.
The volume of tin melted on top needs to be leveled; for this, at the moment of cooling, the solder is smoothed out with a wooden block.
When the tin and the part have cooled, the surface is sanded with a grinder or grinder. The result is a flat, smooth surface that doesn’t even have to be puttied. Using fine sandpaper you just need to remove roughness from the coarse abrasive, then degrease the soldering and paint the part.
On the reverse side of the restored body part, tin streaks may appear, which can be left or, if desired, cut off. If a narrow crack is soldered, then the solder will not leak out at all. This is a very reliable method of repair, which ensures that the tin does not separate from the aluminum, but will stick like a seam created by argon welding.
