Boiled Linseed Oil

Linseed oil, also known as flax seed oil is a clear to yellowish oil obtained from the dried ripe seeds of the flax plant. The oil is obtained by cold pressing, sometimes followed by solvent extraction.

When used as a wood finish, linseed oil dries slowly and shrinks little upon hardening. Linseed oil does not cover the surface as varnish does, but soaks into the (visible and microscopic) pores, leaving a shiny but not glossy surface that shows off the grain of the wood. Wood treated with linseed oil is resistant to denting and scratches and is easily repaired, but the surface is not as hard as Tung Oil, and the wood will slowly absorb moisture if allowed to stay wet. Soft wood is protected from denting, but requires numerous applications and even more drying time than harder wood. Garden furniture treated with linseed oil may develop mildew. Oiled wood can be yellowish and can darken with age.