Brazing Cracks In Thin Sheet Metal

In most cases an overlapped joint will be stronger and braze together easier than a gapped joint.

Brazing cracks in thin sheet metal.

Quench only after the braze filler metal has solidified to avoid cracks or rough braze joints. Extend the excavation at least 1 2 inch beyond the visible crack tip. Finally brazing fluxes have a tendency to cause hydrogen embrittlement in the metal adjacent to brazed joints and this can cause cracking in that metal as panels vibration cycle over miles and time. Did you want to learn how to work around that and deliver a solid re.

Position the metal as desired. A convenient method of preplacing filler metal is by using a brazing sheet an aluminum alloy base metal coated on one or both sides. Here s a few tips on repairing rust holes in car body panels. Because of this you don t need the base metals to be similar so it s possible to tig braze copper to stainless steel as an example.

You should now have a complete joint penetration weld that is as strong as the original member assuming it is low medium carbon steel. A third method of applying brazing filler metal is to use a paste mixture of flux and filler metal powder. Do not quench materials with large differences in coefficients of thermal expansion to avoid cracks in the base materials and tears within the braze alloy. Weld the excavation from the outside.

Brazing is done at lower temperatures without melting the base metals. Heat treatable or core alloys composed mainly of manganese or magnesium are also used. Apply the brazing rod to the joint while continuing to heat the metal surfaces. Grind the outside of the crack down to sound metal about 1 2 the thickness of the base metal.

Braze welding unlike brazing goes beyond capillary action and deposits a strengthening thickness or bead of brazing material in braze weld. The filler material flows into any and all microscopic crevices in the metal and pulls the pieces together similar to a permanent velcro. In this video im showing you the process i use to do small rust repairs where a complete panel. If needed use clamps to secure the pieces in position.