When a finish has deteriorated to the point of cracking and peeling or some other finish ailment, it may be desirable to remove it before refinishing.
Sanding effectively removes pigmented stain finishes. Galvanized nail heads should be set below the surface before sanding to protect the coating and prevent nail stains.
Water blasting is an effective way of removing old finish and grime and preparing for a new finish. A fine, high-powered spray effectively removes loose materials without damaging the wood.
The use of a paint and varnish remover is another way to remove a finish. Several kinds are available. Before using, test the preparation on a piece of new, clean redwood to make sure it will not discolor the wood-particularly if a natural finish is to be used. Film-forming finishes can be removed with a paint and varnish remover. Heat is another method of paint removal.