Dado blade to the rescue
Well, if you remember yesterday, my screws weren’t long enough to attach the 7.5 inches of insulation and strapping to the roof. Alas.
Overnight I figured the only way out of this mess was to rip some dados in the polyiso and put my strapping into the dados. Thereby recovering the depth I needed to get my screws to grab.
Glued but not screwed
The top layers of insulation are in place. Nothing I can do. So I rip out channels with the circular saw and then chisel and scrape with the chisel. It’s ugly but it works and I get the first two dado channels cut.
Success. The strapping goes into the dados and the screws bite into the wood. The roof is saved.
For the next sheets I pop dado blades into the table saw. I look for my el cheapo set, but only the good set is handy. Setting the blades backwards, which for reasons I don’t understand, is the recommended procedure for cutting insulation, I cut two more dados per / in the next two sheets. 4 dados in the time it takes to sing doo dah day.
Plus, working on the ground, not up in the air, joy. And the result is pure clean beauty. The sheets of polyiso go up. And all is good.