Preparation of the surface for french polishing is extremely important. Any slight imperfections which might not be noticeable under varnish or oil finishes would be apparent under French Polish.
It is essential, therefore, that the surface is clean and fine sanded. Furniture that is being renovated should be cleaned to make sure that it is free from wax and grease. This can be done with white spirit and fine steel wool. If the finish on the furniture is in a very bad condition, and is scratched or stained, it would be best to remove it completely with paint and varnish stripper. If, after stripping, the wood is still stained, it may be bleached with Rustins Wood Bleach.
If the wood is open grained and a smooth mirror-like surface is required, the grain should be filled, before french polishing, with Rustins Grainfiller, or extra coats of French Polish must be applied which are then cut back with fine glass or garnet paper until the grain has been filled with the polish. If the wood is to be changed in colour, it may be stained before french polishing, with Rustin's Wood Dye. This is supplied in 10 wood shades which may be inter-mixed to make a wide range of other shades. If the grain of the wood is to be filled with Grainfiller and the colour changed, then the filler can be mixed with the Wood Dye, so that staining and filling can be carried out in one operation.
It should be noted that wood can only be stained to a darker shade than its existing colour. If the wood is required a lighter shade, then it must be bleached first and then stained to the required colour.
Holes and cracks should be filled with wood filler before polishing, but it should be noted that where filler has been used, it will always be noticed, as the pattern of the grain has been broken. The area filled can be made less noticeable by painting a grained effect over the Stopping with artists colours and a fine artists brush.