Re-Finish Wood Trim

-- Last Updated: Jun-25-10 3:03 PM EST --

Have some basic questions on maintaining the wood trim on my boat. Any guidance would be highly appreciated.

On my bell wildfire, is it necessary to back the screws out on the gunwales to refinish the wood or do I want to leave the screws alone and just hit the exterior surfaces? Planning on removing the seat and thwarts to be able to reach everything easier.

Also, it is my understanding that bell uses watco oil. I have a can of UV blocking spar varnish (P&L vitralite) that claims it is suitable for marine use.

Guessing that I should stick with the watco oil?

And... is 180-220 grit about right for preparing the surface?

Some like varnish, but many of us
find that varnish gets chipped, cut, scraped, etc. so that it does not deliver the desired sealing. So instead we use oil, and re-oil maybe every few months.

For a serious job, I would back the screws out (not all at once, in small batches) so as to get some oil into the screw holes. I usually use Watco exterior, unless I have Minwax 209 left over from furniture work.

many options
You might try a search on this topic. It has come up many times.

In terms of refinishing wood gunwales, many different options exist and have their proponents. Danish penetrating oils such as Watco and Deks Olje, Gunwale Guard, Tung Oil, Teak Oil, etc.

Some make up a mixture of boiled linseed oil, turpentine and vinegar (in various proportions).

There are advocates of bright finishing gunwales using varnish. Varnish looks nice but scratches. If the boat is used lightly, it may last quite a long time. I often use varnish on yokes, thwarts, seat frames, and carry handles, but prefer oil on gunwales.

You don’t need to back out any screws to apply oil. Depending on how the boat is used and stored, it may be a good idea to take off the inwales and outwales every five years or so to oil the surfaces that butt against the hull that don’t get oil.

Be sure to wipe up any oil that drips or runs onto the hull before it dries. Once it dries it can be hard to get off. After applying oil, rub off any excess or it can get quite gummy.

Medium paper of around 120 grit is probably fine. Sand along the grain. The wood grain hides any sanding marks from this grade of paper. Some people wet sand with fine or extra fine paper after applying oil (anywhere from 220 to 1500 grit) to try to achieve a furniture-like finish.

Watco also makes a Satin Wax that can be applied. I have used both the interior and the exterior Watco oils on my gunwales and haven’t noted much difference.


– Last Updated: Jun-25-10 4:09 PM EST –

Have had the boat for about 3 years and never got around to it. Has been garage kept, including the previous owner, but not sure if any prior maintenance was done before I got it. Seems to be in pretty good shape except for some marking that I believe happened on roof top carrier.

A quick sanding and oil rub does not sound very time intensive... should have found a couple hours to get it done.

How difficult is it to line up the rails again if I were to 'back oil' them.

Lazy man’s touch-up
If your boat is garage-stored then it probably needs minimal attention.

One quick way to apply oil finishes is by wetting a ScotchBrite pad and rubbing it in. Sands and applies in one step. Still gotta wipe it down though.


The wood appears to have some type of finish applied… not a high gloss, but not completely dull either. Perhaps it is a varnish.

not really too hard

– Last Updated: Jun-25-10 4:49 PM EST –

The stainless steel wood screws usually back out pretty easily but if the wood trim has been oiled, the Philips head slots may be filled with gunk and dried oil. Use something pointy like a scratch awl to "degunk" them before backing them out so you don't strip them.

The last half-dozen or so screws near each stem are often longer because they may extend into the deck plates. Don't mix these longer screws up with shorter ones when you reattach the gunwales or the longer screws may go right through your outwales.

It can be hard to find a place to support and work on an 18' long, thin strip of wood. I have sometimes detached the inwales and outwales from only one half of the boat at a time to sand and oil the interior surfaces.

On composite boats usually either the inwale or the outwale is rabbeted so that the top of the hull is hidden under the wood. When reattaching the inwales and outwales to the hull, it is often convenient to use some soft jaw spring clamps to approximate the wood pieces to the hull before you reinsert the screws.

On many boats the deck plate is glued to the inwales. I have generally found it possible to lift out the inwales and attached deck plate to work on the wood without breaking the glue joint.

Ditto the Scotch Brite pad
it’s worked for me for decades. Unless your wood is REALLY bad, and it shouldn’t be if garaged, that’s the easiest way to apply and smooth the rails.

slow start
Thanks for the detailed replies.

Decided to start with a different boat that is stored outside. After removing the hand holds and one thwart I used a 3m pad and a bucket of mild soap on them.

They seem to be varnished and had a couple places where the finish was worn. Also a little bit of mildew growth near the end grain and bolt area. Sanded the two hand holds down to almost bare wood… still a little stain showing and perhaps mold? in the open areas of the grain. The area near the endgrain is starting to show signs of cracking in a couple spots and there is a slight smell of rotton wood also. Not horrible, but the start of a little damage under the varnish.

Is it possible/worth it to try and save these a for a little longer? Thinking about completly sanding off the varnish on the other two thwarts, scrub with bleach, and another round of sanding for starters. Not sure how to deal with the end grain area yet.