Hello,
1. I plan on using POR-15 and Bher black exterior enamel on my white oak boards. After applying the POR-15 do you scuff or use the POR-15 etch primer before applying the Bher paint?
My understanding is that if you don't wait too long between coats, the POR15 does not need scuffing. Look again at the test information where we detailed the procedure. Three coats of POR15 3 hours apart and the first coat of BEHR black 3 hours after the last coat of POR15. Paint has a "Window" of opportunity where the adhesion is best. Wait too long and it does not adhere as well, paint too soon and it does not dry properly. Check POR15 application information to make sure it has not changed. Of course all paints don't have the same time window.
Like I have said before, that black has been exposed outdoors 24/7 since the test began and still no failure at all. You will have to coat all surfaces of the boards, especially the ends to get those results.
Mar-Ktech
