This is a bit off topic but I need some advice about constructing a wooden sculpture that will be outside for at least a year. It will have to survive rain, direct sun, freezing in winter and baking in summer. It'll be in the middle of Kansas. I thought boat builders might have some insight about adhesives for this project.
The piece is a figure about 6' tall, standing on one leg and taking a step with the other (raised) leg. I will make this by laminating 2x12 lumber, using glue and dowels. Then I'll refine the contours using a belt sander and rasps. The mating surfaces will not be machined flat and square so there may be some gaps in the glue film. The lumber is untreated pine.
After the figure is shaped, I'll prime the hell out of it with an oil primer, then give it two coats of paint for the final color.
I'm concerned about what type of glue to use. A lumber store suggested floor mastic as a waterproof material but I worry this would be too flixible and allow the laminations to creep apart. What would you suggest as an appropriate adhesive for this project? Also, would the type of paint I use have any effect on the selection of glue?