Method for finishing a thermoplastic coating

A method for simultaneously finishing a substantially thermoplastic coating of the type which dries by solvent evaporation, on both major faces of a wood door, comprising the steps of:

• (a) moving said substantially vertically oriented coated wood door in a predetermined direction at a predetermined speed;
• (b) engaging each face of the moving door with one of a first pair of revolving cylindrical brushes, each brush having nylon bristles impregnated with an abrasive, the brushes revolving in the same rotational direction at predetermined speeds;
• and
• (c) engaging each face of the door downstream of the first pair with a second pair of brushes, each brush having nylon bristles impregnated with an abrasive, the brushes of the second pair revolving at predetermined speeds in opposed rotational directions to impose a force to the door resisting its motion in the predetermined direction.

A method of simultaneously finishing opposing faces of a workpiece product having on each face a substantially thermoplastic coating that dries substantially by means of solvent evaporation, comprising:

• contacting each coated face of said workpiece with one of a pair of rotating vertically aligned brushes, said brushes spaced apart such that the brushes at rest just touch both faces to be finished;
• moving said coated workpiece between said brushes, wherein said workpiece is vertically supported by said brushes which contact the surfaces to be finished;
• and
• adjusting the speed of rotation of said brushes, contact pressure and speed of the moving workpiece, heating said coating by friction of the brushes to just the thermoplastic temperature of the coating, said coating in response to said brushes remaining in a softened flowable state, but adhered as a film to said workpiece, until said solvents have substantially completely evaporated and said coating solidifies into a smooth, nap-free finish on said workpiece.