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Welding

Welding

When welding, the negative lead of the battery must be disconnected and covered. See Procedures after battery disconnection.

Warning

It is extremely important that satisfactory spot extraction equipment is used when carrying out work that generates heat, such as welding, grinding, cutting and drilling.

Therefore, supplement the protection with efficient respiratory protection such as a face mask with carbon filter or, preferably, a fresh-air mask.

When heated, all paints, sealants, adhesives and anti-corrosion agents emit harmful substances.


Symbols

The following symbols are used for the different welding methods in method descriptions:



1. Spot weld drill

2. Spot weld or plug weld

3. Spot weld drill through two panels.

4. Cutting

5. All weld, continuous seam

6. Seam weld


Grinding

All surfaces to be welded must first be ground clean of any paint. Use a belt grinder. When spot-welding galvanized sheet metal, the paint must be removed with a steel brush and hot-air gun so that the galvanized surface is not damaged. All-welded and plug-welded details must be ground to a fine finish after welding.

Important

Be careful not to grind away too much metal. The strength of the material must for no reason be reduced.


Use abrasive cloth 120 or finer on external surfaces. Coarser abrasive cloth leaves marks that will be visible after painting.

Welding

The characteristics of the body deformation zones and cabin enclosure must not be changed or compromised after repair. Therefore, it is important that all welding work is done according to the method descriptions and that the correct welding method is used in the correct places. Spot weld rather than plug weld if space allows for it. Always check the number of spot welds and their location before removing the damaged part and use the same number in the same positions when fitting the replacement panel. When spot welding, the diameter of the electrodes must not exceed 6 mm. The core of the spot weld must be 5 mm in diameter to ensure high strength. It should be possible to put a screwdriver between two spot-welds and strike it with a hammer without the welded joint braking open. Welding primer must always be applied between the metal sheets being spot welded. Use Teroson Zinkspray.

When MAG welding, make sure that the grounding of the welding unit is 100% and connect the ground cable as close to the welding point as possible. This is important in order to be able to weld without first removing all electronic units from the car.

Important

If good grounding is not ensured, electronic components can be damaged by current surges through the body metal.


Welding galvanized sheet metal


• Use a wire brush and hot-air gun to remove any paint from the surface. A grinder can remove the galvanized surface and must not be used.

Important

A bare galvanized sheet metal surface begins to rust immediately. When grinding galvanized sheet metal to bare metal, it is important to apply primer to the bare surface within minutes. Use an acid-hardening (etching) primer.

If filler is to be used on the surface, use only epoxy primer.


• Galvanized sheet metal should be spot welded. Weld using slightly higher temperature and pressure than for ordinary cold-rolled sheet metal. Apply a zinc-based weld primer between the surfaces that are to be welded together.

• Use a welding rod suitable for galvanized sheet metal, for example, "Magsi 54", as well as an ordinary, controlled atmosphere of mixed gases type for MIG-welding.

• For filling work, use special filler for galvanized sheet metal, for example, Top filler (10) 82 85 488, with Standox hardener (10) 82 85 496.

• Working with galvanized sheet metal requires a higher standard of protective equipment than ordinary cold-rolled sheet metal.


All new methods and materials can be used on cold-rolled sheet metal.