Maintaining Door Finishes

greetings,

i just received a call from a brownstoner asking me about maintaining wood entry door finishes. there is something written on the tinkerswagon.com about doing this but i will state some of this briefly here:

first, use genuine marine varnishes from the boat yards on these doors. these include epifanes, pettit, and interlux. all three of these are carried at west marine, the closest of which i now believe to be in port washington/manhasset. they closed 34th st in the city a couple years back and long beach is closed. the interlux is carried at venice marina off the belt parkway. i think that is near king’s plaza. there is another marina east of king’s plaza and east of the home depot there that carries some of these products.

do not use interior or water base exterior product on entry doors. the interior products are too hard (marine products are softer so they can change with climate conditions). the interior oil base products crack and peel. the exterior water base products wear easier. this includes the General Finishes 405.

do not use mckloskey man o war. it is soft enough and will not crack but for some reason it often turns white after a few years.

if you have used a mcklosky finish and you see it turning a little white, it might be possible for you to lightly sand the whitening off with 180 or 220 sanding sponge or paper. go lightly and to not oversand or sand the edges as you could sand right through the finish and sand any stain off and touching up missing stain will create challenges. if you must try 150 grit, so be it, but the lines will be visible after top coating so you will have to sand them out with 180. dust after sanding. tack cloth.

then over coat. i am not going into what to do to fix worn spots here where wood has become grayed. it can be fixed. but it take a little more skill. i am stating how to do this for apply one or two coats over an otherwise good finish that might have whitening or might have some scratches or be wearing thin.

to overcoat, apply full strength. one coat and let it dry overnight. if you let it dry say over night and no more, and you know it is dry, you can get away with applying a second coat without sanding a little to scuff the surface. if you wait 2 days for the next coat, you must sand and tack between coats to allow for “mechanical bond”.

you can apply many coats of marine varnish. many coats. it is soft and this means it will not chip off. some of the sailboat guys overcoat every year for the hell of it. we cannot do this on wood floor with interior oil base poly floor finish (and maybe water base), because it is so hard that if we build to many coats, it will chip. marine varnish is soft and pliable.

one way to tell if your marine varnish is aging and at risk of failure is, look at it and see if its gloss has faded. when that fades, it is time to consider over coating.

as with many other things, the sun is the enemy.

also, apply at least one coat of varnish to the door bottoms. the wood near the saddle wicks up moisture and swells and then the sun his the lower front of the door and this dries it on the outside and shrinks the wood near the surface and this stresses and ages the varnish.

always keep a record of all stains and varnishes and paints used on your home. fyi, i have a book in my shop where i recorded all details of finishing work right down to the sanding grits and amount of drops of dye put into stains or top coats in case any customers call me if they have to repair a finish. you have to do this-

for serious consultation on larger projects and building maintenance, i do offer maintenance consultations.

Amazon sells Interlux spar varnish which has worked well on my doors, with a couple of coats every other year