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Re: Material: peeling paint
By:Paul G. Jacobson
Date: 2/4/2008, 2:09 pm
In Response To: Material: peeling paint (Marie)

: . . . The only problem is I've never heard of clear
: primer and can't find any. Has anyone heard of it or used it? . . .

Well, the term "clear primer" is not the brand name or product name of any particular product. It is really a generic term which coavers all the various materials which can be used as primers, and which have no pigment in them.

Among your options would be materials which are oil based, lacquer based, alcohol based, and water based--just to start. Here is list, which is by no means complete, but jsut what comes off the top of my head:

Shellac--This is alcohol based and comes in either a "white" variety or an "orange" variety. It is very thin, and when used as a primer it is cut with additional solvent (denatured alcohol) so it is even thinner. Applied in a thin coat it soaks rapidly into the pores of the wood. When the alcohol evaporates ( usually inside of 30 minutes) the resulting film of dissolved natural resin seals in the natural oils of the red cedar, and provides a good base for your paint. With the thin application you are using you'll not be able to tell any difference between white or orange. The orange variety is sometimes a bit less expensive. The "thickness" of a shellac is expressed interm of how many pounds of resin are dissolved in a gallon of alcohol. Standard is about a 4 pound cut (4 pounds of resin to a gallon). For a primer you can reduce this to the equivalent of 2 pound cut, or 1.5 pound cut, by mixing with your solvent. A 4 ounce can of 4-pound cut shellac, mixed with 4 ounces of alcohol gives you 8 ounces of primer, which should treat about a dozen GPs with one coat, or 6 of 'em with 2 coats.

Lacquer comes in clear, black, and a variety of colors. This is a man-made resin (nitrocellulose) dissolved in a nasty solvent which evaporates at a very rapid rate. You can use it like shellac, but it is sometimes more expensive. Clear lacquer is very transparent. It also soaks deeply and rapidly into the wood. The solvent evaporates very fast. If you use an aerosol spray can, the lacquer will be almost dry before it hits the surface of your paddle, and won't soak in very deeply. You can recoat in 2 or 3 minutes. Mist on 4 almost-dry layers (never let it puddle or run), wait 5 minutes and give it a light sanding. Or, paint on a thicker layer and let it soak in and give it 20 minutes to harden. Then sand off anything that stays on the surface.

Epoxy resin can serve the same purpose, but it soaks in more slowly and takes longer to harden.

You can use a thined coat of varnish as a base coat or primner. To one ounce of spar varnish add 1/10th ounce ( 10 %) of solvent.

In the varnish family you have the natural resin varnishes as well as the urethane and polyurethane coatings. Those urethane and polyurethane coatings come as either solvent based or water based. They also come in a variety of gloss finishes (glossy, semi-gloss, matte, etc.) If you are sensitive to vapors from solvents, use a water-based urethane or polyurethane, thin it slightly, apply one or two very thin coats, and sand lightly before applying your flourescent paint.

In spray cans you can also find Krylon(r)clear acrylic spray "paint" which should give a good base coat. Spray it on, let it dry, sand it down.

Good luck with your choice. This is quite a list of options. Something will be available near you, at a reasonable price.

PGJ

Messages In This Thread

Material: peeling paint
Marie -- 2/4/2008, 11:51 am
Re: Material: peeling paint
Bill Hamm -- 2/6/2008, 2:08 am
Re: Material: peeling paint
Paul G. Jacobson -- 2/4/2008, 2:09 pm