I still prefer oil-based stains for sandblasted sign backgrounds. Although I loosely use the term “oil-based” I am referring to mostly alkyd-based paints, that use modified polyester-based resins. These types of stains and primers soak in deep and are more thoroughly absorbed into the pores of the wood surface than water-based varieties.
So here’s what I have found works best when coating raw cedar, redwood, and mahogany that will be used for outdoor signs: If the sign’s background is flush with either carved-in or painted-on letters, I recommend a quality oil-based primer for the first coat, (Zinsser is what I like best). Then I’d recommend a high-quality latex for the top coat, using a paint with a high-gloss or at least semi-gloss sheen. I used to always prefer oil-based top coats, like bulletin enamels, but have found through my extended experience that these tend to produce very hard- but eventually more brittle- films, that over time crack and peel at a much greater and much earlier rate than the more flexible acrylic coatings. Plus, if pigmented in reds or some blues, the oil-based colors fade faster than acrylics.
When coating a sandblasted sign background, I highly recommend using an oil-based stain, one or two coats depending on the wood type, condition and porosity. No primer is needed as the stain acts as the primer and finish coat. So in these instances, the old-fashioned oil-based paints are still my preference.
If you’re in the market for quality hand-painted signage, please give me a call at 540-943-9818. I’ve been making high-performance wood signs for many decades!
Mark Hackley owns and operates Augusta Sign Company serving Staunton, Waynesboro, and surrounding areas of Virginia. You can e-mail him at firstname.lastname@example.org.