Brazing Cracks In Thin Sheet Metal

Brazing is done at lower temperatures without melting the base metals.

Brazing cracks in thin sheet metal.

Heat treatable or core alloys composed mainly of manganese or magnesium are also used. A convenient method of preplacing filler metal is by using a brazing sheet an aluminum alloy base metal coated on one or both sides. The filler material flows into any and all microscopic crevices in the metal and pulls the pieces together similar to a permanent velcro. Grind the outside of the crack down to sound metal about 1 2 the thickness of the base metal.

Quench only after the braze filler metal has solidified to avoid cracks or rough braze joints. A third method of applying brazing filler metal is to use a paste mixture of flux and filler metal powder. In this video im showing you the process i use to do small rust repairs where a complete panel. Did you want to learn how to work around that and deliver a solid re.

Weld the excavation from the outside. Here s a few tips on repairing rust holes in car body panels. 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. 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.

Apply the brazing rod to the joint while continuing to heat the metal surfaces. Have you ever welded something so thin and worn out that all you do is blow holes in it. If needed use clamps to secure the pieces in position. You should now have a complete joint penetration weld that is as strong as the original member assuming it is low medium carbon steel.

Extend the excavation at least 1 2 inch beyond the visible crack tip. In most cases an overlapped joint will be stronger and braze together easier than a gapped joint. Braze welding unlike brazing goes beyond capillary action and deposits a strengthening thickness or bead of brazing material in braze weld. Note that quenching can affect base material mechanical properties.