Repair deformed surfaces by mechanical or thermal action on the metal, as well as by filling dents with quick-hardening plastics or solder.
Straighten the rumpled places of plumage, manually using a straightening tool (metal, plastic, wooden hammers and various mandrels) and fixtures.
Use heated straightener for upsetting (contractions) highly stretched panel surfaces. To prevent sharp swelling and deterioration of the mechanical properties of the panel, it is heated to 600-650°C (to cherry red). The diameter of the heated spot should be no more than 20-30 mm. To tighten the surface with a gas burner from the periphery to the center of the defective area, heat the metal and, with the blows of a wooden mallet and hammer, precipitate the heated places using a flat support or an anvil. Repeat the heating and upsetting operations until a smooth surface is obtained.
Irregularities in the panels can be smoothed out with polyester fillers, thermoplastics, cold curing epoxy putties and soldering. Polyester putties form reliable bonds with panels that have been stripped down to metal. They are two-component materials: an unsaturated polyester resin and a hardener, which is a catalyst for the rapid curing of the mixture, regardless of the thickness of the putty layer. Drying time at 20°C is 15-20 minutes. At the same time, there is no need to apply it in several layers, which reduces the duration of the putty application.
The thermoplastic is available in powder form. Elastic properties necessary for its application to the metal surface of the panel, it acquires at 150-160°C. Thoroughly clean the surface to be filled of rust, scale, old paint and other contaminants. For better adhesion, it is recommended to create roughnesses on the metal surface using an abrasive tool. To apply thermoplastic, heat the area to be leveled to 170-180°C and apply the first thin layer of powder, which is rolled with a metal roller, then apply the second layer, etc. until the unevenness is filled. Roll each layer until a monolithic layer of plastic mass is obtained. After hardening, clean the layer and level it with a grinder.
Corroded sections of body panels can be repaired with cold curing epoxy putties, which have high adhesion, sufficient strength and are easily applied to damaged areas.
Solders POSSu-18, POSSu-20 are used for leveling areas, building up the edges of parts and eliminating the gap. Use an acid-free soldering method to prevent metal corrosion.