Producing relief type patterns in wood fibre sheet surfaces - using hard and soft sections applied to surface and subsequently eroded by abrasive treatment

A system for production fo relief type structured surfaces on a wood fibre sheet, has sections constructed on at lest one side of the wooden sheet by means of initially, loose fibre pastules. Some of threre sections are distinctly harder than others, such that generally all the sections lie in the same plane. The whole surface is then given an abrasive treatment, such that initially fibres of softer sections are removed, whilst the harder sections remain roughly flat and lie proud to the sections of softer material which have been removed.