Refinish old oak door
The original quarter sawn/tiger oak door on our 1907 bungalow is in need of refinishing. The lower portion of the door has milky residue and the wood grain could be enhanced by a refinish job. I am hesitant to approach this the wrong way because this door is a real treasure. My plan is to sand it lightly to remove any lingering varnish, bring out the grain and simply revarnish with tung oil or spar varnish. Should I restain the wood? If I sand too hard will I damage/remove the grain? I can't tell if it has been stained or simply varnished. Thanks for your expert advice.
Re: Refinish old oak door
A door of this age is almost certainly solid wood. A vigorous sanding would not damage the grain. If you are intending to stain the wood, you must totally remove the old finish, otherwise the stain will be absorbed unevenly and look splotchy. Staining is not neccessary other than to affect the final color. It has no effect on the protection of the wood.
Tung oil in not suitable for an exterior door. It might be OK if the door is totally out of the rain and sunshine. Better would be at least three coats of a spar varnish. Don't forget the top and bottom edges of the door, especially the bottom. End grain is particularly vulnerable to water absorption.