applying marine spar varnish?

[Helen Gee]

Hiya,

Hope this is not too silly of a question. I was at woodcraft and the folks there suggested I try marine spar varnish for a purple heart project I'm working on to delay the purple from changing colors.

Is this similar to oil finishes where you saturate the wood and then wipe off any excess after the wood stops absorbing? Can you wetsand it?

Thanks,
Helen

[Cecil Arnold]

Helen,

Marine spar has a high level of UV filters. It is normally brushed on with the first coat being thinned about 50/50 followed by three coats of full strength. You can wet sand it so long as you don't go through the final coat.

[Helen Gee]

Thanks Cecil! I'll give it a try tomorrow!!

[Steve Schoene]

You do understand that Woodcraft doesn't really sell a traditional marine spar varnish. The brands widely respected in the "yachting" community are Interlux Schooner, Pettitt Captain's, and Epifanes Gloss. You will find these only at boating supply stores (chandleries) including on-line unless you live in a boat mad community.

Spar varnish is a bit on the soft side for most furniture uses. And, to be effective it must be applied, after the first coat, in nearly fully strength coatings--there is no point in trying to use it as a wipe on finish. It would work in a sense, but the UV protection depends on the thickness of the coating. Most of the label directions will call for 6 coats. For boaters trying to keep finish on in the sun that's OK for the North, but considered a bit light in tropical waters. The UV absorbers do breakdown over time--that's how they work--so you would want to periodically want to sand down the top coat and apply a fresh coat periodically.

What sounded to me like the best advise to keep purple heart purple is to use a purple dye to set the color. A pigmented stain, particularly if you search for a light fast pigment, would work even better, if you can accept the loss of clarity of the stain.