Here are some basic procedures for preparing a piece for welding. Following this will result in the best possible outcome.
- Remove all oil and grease.
- Grind away rust and pitting.
- Chrome plating: Flash chrome, in general, does not inhibit the welding process. However, heavy chrome plating will crack and lift from the heat distributed during the welding process. Therefore, in heavy chrome applications, the chrome should be stripped away before welding.
- Nickel plating: In general, light nickel plating is weld-able. However, when welding heavy nickel plating, the nickel will melt away from the heat of the torch causing a sunken area around the border of the welded area. This effect may result in an unacceptable finished surface. Heavy nickel plating should be stripped before welding.
- Titanium nitriding: This treatment is weld-able; however, it can require stoning around the edge of the edge to remove the transfer of heat caused by the welding torch.
- General nitriding: This can be welded, but the welding process will leave pitting in the weld area, which will require a touch up after machining.
- Carburizing: This treatment is not weld-able. All carburized tools should be surface before welding.
- Plastic: Remove all plastic from cracks and corners that are to be welded. If the plastic cannot be removed from a crack, then the weld should be ground down enough to all for several layers of weld. When using this repair procedure, the initial layers of weld will contain blowholes and cracks caused by the mixture of weld and plastic; however, the final layers of weld should result on an acceptable finish.
- EDM finish: EDM finishes can have a very hard re-cast layer that acts as a barrier to the melting of the steel. As a result, the torch heat must be increased substantially in order to break through this hardened surface layer. Therefore, the re-cast EDM finish can cause major difficulties, especially when welding intricate areas. In these situations, grinding down the re-cast layer will result in better-ability.