How to: Porcelainize Steel
- 1). Clean the steel metal surface with a good quality degreaser. Remove any manufacturing residue or oils which remain on the steel as a result of the manufacturing process. Petroleum products are used to cool machinery or lubricate forged or stamped steel parts. These residues will prevent the porcelain from adhering to the steel surface.
- 2). Fill any imperfections in the metal which remain from manufacturing. More a problem when you're working with cast metal objects, any pits or voids in the surface should be filled with a high quality liquid metal. Sand the surface when the filler drys. Also file off any casting flashing that may remain on the object from the casting process.
- 3). Spray the primer coat, sometimes called the ground coat, with a low-pressure porcelain coating paint gun. The spray gun applies the coatings quickly and evenly, which is important when priming any painted surface.
- 4). Heat the primed metal in a temperature-controlled furnace. Freestanding furnaces, or glass kilns, are well-suited for this step. Steel with ground coats are heated at a temperature of 980 degrees Fahrenheit for 10 to 12 minutes. These parameters may change based on the type of steel or the brand of paints used. Check the coating manufacturer's instructions while preparing for this step.
- 5). Immediately apply a second or finish coat of porcelain with the spray gun to the hot primed metal object. The second coat will adhere to the object before it's fired because of the steel's elevated temperature.
- 6). Complete the project by firing the steel item a second time. Recommended parameters for the second step are 1000 degrees Fahrenheit for 1 to 2 minutes. Because of the elevated starting temperature of the primed metal, the second firing is much shorter than the first.
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