The effects of pneumatically propelled abrasives in removing a finish on open and closed grained woods

This research evaluated the possibility of using pneumatically propelled abrasives. to remove a finish from an open and a closed grain wood. This investigation was done on lauan (Philippine) mahogany and birch test panels that had been sprayed with a commercial lacquer. Major findings included:

1. The angle of the nozzle must be low to keep the force on the top surface of the panel as uniform as possible throughout the blasting operation. Due to the scattering and collision effect one cannot achieve an infinitely small and/or perfectly uniform angle between the nozzle opening and the test panel.
2. The nozzle opening should be as flat as possible. The distance between the nozzle opening and the panel should be as uniform as possible to reduce the scattering effect. These two variables help keep the abrasive more directional.
3. The abrasive used should be a very fine, dense, and angular particle which will cut the finish and surface of the wood rather than beating and uprooting large chunks of finish and wood. If the particles are fine enough, the cutting effect should be uniform.