Brightwork varnishing - filling open grain

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lpaulcarter

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I'm in the middle of a brightwork refinishing project, and wondered if there is still any kind of "grain filler" available on the market. The brightwork I'm working on had to have some areas stripped to the wood, and in order to achieve a level finish on the damaged areas that matches the glasslike surface of the surrounding area, I've had to apply 5 coats of varnish. Is this the only way? Years ago I remember stain/fillers were used to fill the open grain of woods like mahogany, then when you applied varnish, the result was a pretty smooth surface from the first coat. I've been unable to find any products like this, and have been told they are no longer available, but not why...
 
I always thought that at least 6 coats was the START of a varnish finish.
Al
 
There are a number of good fillers on the market. The best one for you to use depends upon the wood and what type of finish. Go to a local "good" paint store, (not a lowes, home depot, etc) and ask then what they have. I always use a filler when I am working with oak.

G
 
The only way to correct surface imperfections in wood prior to varnishing is to sand down to good wood. In restoring some of the old wood on our boat, I've had to start with 50 or 60 grit and work up the steps to 120 or 150 grit. Many areas in good shape could be started with 80 grit.

A number of paint companies still make oil-based filler stains for marine use. The ones I use are made by Interlux, Pettit or Sandusky.

It's not the filler stain that provides the flat finish, it's the varnish. After filler stain and sealer, I put down at least five heavy coats of varnish lightly sanded between coats. After coat five or so, I give it a much more aggressive sanding to flatten the vanish surface as much as possible. After coat eight or nine: another aggressive sanding to flatten. Another three or four coats later and you will have flat, glossy varnish. The traditional spar varnish I use has a UV inhibitor (Pettit BAK-V-SPAR.) Pettit recommends a minimum of eight coats, but the more the better.
 
Anytime I have to take wood all the way down, after I sand through progressive grits winding up aroun 800, I thin the first two or three coats of varnish 50/50 with a good thinner so that it soaks into the wood and doesn't just sit on top of it. And as losta1 said, about six coats is the starting point, sand lightly between each coat for adhesion and more aggresively after several coats to level. A good brightwork finish will take weeks to accomplish but if it's taken care of won't have to be repeated very often, just touched up.
 
I’ll offer a different perspective on exterior varnishing for boats. I use hand sanding only.

For hand sanding of wood, including mahogany, oak and fir: do not use finer than 120 grit for the final sanding or the mechanical bonding of varnish to wood will be compromised.

For hand sanding between varnish coats, use no finer than 220 grit. Again, a finer grit will leave too little surface area for the fresh varnish to bond to the older coat. Hand sanding large areas of varnish is much faster than using an orbital power sander.

Thinning the initial varnish coat up to 50/50 helps varnish penetrate both filler stain and wood. Pettit Clear Sealer is a modified spar varnish that is specialized for this purpose: it's thinner, has a higher oil content and is faster drying than varnish. The additional oils promote penetration and improve the flexibility of the cured product. IMHO, Pettit Clear Sealer is a better primer for varnish than thinned varnish.

The exterior varnish on my boat gets yearly recoats, and is going on its 11th year.
 
I've got 8 coats on the areas in question, 5 coats on the stripped spots, with 3 more coats on the entire area. The result is beautiful, as usual. I guess I was hoping to find a way to reduce the amount of aggressive sanding between coats.

yzer: I also use strictly Petit products - Clear Sealer as primer, followed by Flagship Varnish. Here's a question for you: the boat I'm working on now has areas that have had to be sanded down to bare wood (mahogany). The owner does not want me to spend the time (time=money) stripping all of the brightwork down to wood. The areas where I have had to do this come through quite red when wet, compared to the golden colour everywhere else. Will they become more golden with successive coats of varnish, or are they going to stay red, and therefore look different than the surrounding areas?
 
If old stain remains in the wood it will always contribute to color differences between itself and unstained wood.

The areas of golden colored mahogany are either wood without stain or areas in which a "neutral" or "natural" stain has been applied. A neutral stain will actually tone down the natural red color of Philippine mahogany. Does it look like a neutral stain was used on the wood? Unvarnished, this stain looks white to yellowish in color.

You don't need to get every bit of old stain out before refinishing if you are refinshing with the original stain. If you are changing the color: then yes, you should remove all of the old stain to get uniform color.

You could always try a small test section see what happens.

Sanding isn't the only way to rid the wood of old stain. Repeated applications of JASCO Premium Paint and Epoxy stripper will do the job. Sometimes it wil take four or five passes with the Jasco to remove all of the old stain.

A combination of Jasco stipper and sanding worked best for me, but I was refinishing with a fresh application of the original stain, and didn't need to get all of the old color out of the wood.

Bare, sanded Phillipine mahogany will quickly turn golden and darken once its exposed to sunlight. Don't know is this is a factor in the wood you are working with.

The owner is going to have to expect some variations in color if he wants to have stripped and non-stripped areas refinished.
 
Paul, they should fade over time. You scuffed up "new" wood with fresh oils, it needs to bake it the sun a bit.

Yzer, I agree about the 120 grit for final sanding for mechanical bond. I have been using finer than 220 for knocking the shine off between coats. I'll think about 220 instead.

One other thing I discovered last year. Epifanes has a "new" (new to me at least) product, I think its called Woodfinish Gloss. It's a true varnish, though epifanes is a little hesitant to call it one, with the benefit of recoats within a period of time without having to sand. Last year I bought a can of the traditional gloss varnish and this "new" product and applied the varnish to one rail and the "new" product to the other. They say the true varnish has the best shine and recommend it for the final coat, but on my boat its the new fangled product that has the better shine and the recoats are easy AND its really varnish, not some kind of sin like cetol. I'm VERY skeptical of new "varnish" products, but I think epifanes may have a winner on this one. One year later, its wearing wonderfully.

I was going to start a discussion about brush choices, but on second thought that probably belongs in NBR since it's more of a discussion about religion than boating!!! :)

bp
 
The red colour is the actual colour of the wood, not stain. Can I bleach out the red of the wood and then stain to match the golden colour of the nearby unstripped areas?
 
I found bleach (in the hardware store), my problem now is that I don't seem to be able to get any of the filler stains here in Canada. All that's available are the usual furniture stains. Interlux won't put French labels on a lot of their products, so they can't be imported. Pettit's Bak-V-Spar varnish and Clear Sealer are likewise unavailable here. I guess I'm just going to have to make a run to Friday Harbour...
 
I will enter this discussion with another varnish question but this one regarding polys. Many years ago I needed to varnish new ceiling boards for a porch. After staining I used a poly and the directions stated that as long as the poly was recoated within one hour it was fine to do so without sanding otherwise it was necessary to wait 12 hrs until the varnish completely dried and then sand and recoat. I assume this was because within 1 hour a new coat softened the underlying coat and allowed adhesion. I did this for 3 coats [only a porch roof] and it worked wonderfully. The question I have is that the option to recoat within 1 hour has completely dissapeared from the instructions on any of the poly varnishes I have seen. Does anyone know why?
 
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