Sandblasting will effectively remove paint coatings from many surfaces. However the heavy abrasiveness of silica sand can create problems. Sand's abrasive characteristics can be too aggressive for delicate projects. While the sand removes the coatings it can also destroy the substrate. For these reasons, blasting small or delicate projects with crushed walnut shells is an effective means to eliminate this problem.
Identify the items to be cleaned through the blasting process. Separate these items into a room with a high air volume, regulated ventilation system.
Connect the hoses between the blasting media hopper and the sandblasting nozzle, and between the compressed air supply and the blasting media hopper.
Fill the blasting media hopper with crushed walnut shell blasting media. Bring the blasting equipment up to manufacturer recommended pressures and settings. Apply OSHA approved particle respirator, gloves, goggles and protective clothing to cover all exposed skin. Make sure to wear no loose-fitting clothing.
Test blast a small inconspicuous area of the surface to be cleaned. Adjust the compressed air supply volume and pressure and the blasting media supply stream in order to achieve desired results. Higher compressed air pressures, and higher volume blasting media will will result in more aggressive coating removal.
Gently remove coating, grime, or other contaminants from the surface of the product to be cleaned by sweeping the blasting nozzle back and forth over the item's surface. The walnut blasting media will gently remove existing tarnish or oxidation as well as more significant coatings such as paint, grime or grease.