Hello,
When backpriming T&G solid sawn wood, is it best to prime the tongues and grooves, or not? On the one hand, sealing all sides is good; on the other, it would be easy to get excess paint in the corners which could interfere with the mating of the T&G. But the groove is typically 1/16" wider than the tongue, so perhaps that's not really an issue.
Thanks, Wayne