I'm trying to repaint a wooden retail store sign. Its lettering is still crisp, but the rest of the wood it's on has darkened with exposure to weather, making the whole thing less legible.
About the sign:
- The wood is some kind of plywood, apparently designed for use in building boats. I can probably get the technical name of the material
- The wood was barely sealed, or not sealed at all
- The lettering was painted with 1-shot sign-painting enamel (this was probably before their change in formula)
- I want to cover the whole outward-facing section of the sign with color
- The sign is mounted to the storefront, and I do not have permission to take it down. I was told that the mounting is "complicated" and the store owner doesn't want nit futzed with
Constraints and considerations:
I figure that unless I entirely sand off the existing lettering, I have to use oil-based paint, since latex won't adhere well on top of it (right?). I'm worried because I can't reach the back of the sign where it's mounted to the storefront. That means the oil-based paint I apply to the front will prohibit the wood from fully expanding in front, but not in back, increasing the risk of cracking the paint.
I'm also worried about adhesion between the oil-based paint and wood that has been exposed to the outdoors for a long time, no matter how dry it seems to be (I'm waiting for some really sunny days).
My tentative plan so far:
- Sanding the surface of the sign
- Applying oil-based exterior primer (with a roller)
- Applying an undercoat (Is this necessary? I'm unsure) (with a roller)
- Applying oil-based exterior paint (with brushes and a roller)
- Applying 1-shot sign-painting enamel for lettering (with brushes)
Question: Is my plan sound?