I have newly installed, 3-piece crown molding system installed (poplar wood). I anticipate movement in the joints as time passes. I’m looking for the best primer to tolerate the movement as well as to cover any poplar issues. The SW Premium Wall and Wood Primer you recommended looks very interesting but I couldn’t find anything about how well it tolerates movement. Can you help me? Thanks.
The SW Wall and Wood will tolerate the movement just fine. Usually, that is not where issues occur. You are more likely to see issues at caulked joints – not so much inside/outside joints, but the parallel joints in your 3 piece configuration. You would have been well served to back prime all of the pieces prior to installation. This is one of the best ways to create dimensional stability. For now, though, yes prime heavily with the W&W, lightly sand at 220, vac, tack, caulk and paint.