While making tpo rails for our new deck, I thought that "crowning" them would help rain an snow run off. Last time, I ran the two bys through the TS twice with the blade set at 5 degrees or so.
This time, I pulled out the jig I'd made to create a sloped sill out of that plastic deck board material (I needed it to match the edge of the sliding glass door sill and slope downward therefrom for the same reason factory sills do it.
I had some slick plywood sign board material with a slick plastic facing and cut it to less than the width of my planer by quite a bit and wide enough to hold the six-inch wide deck board (face down) between two low guide strips. Underneath this jig, on one side (left), I fastened a little strip of wood thick enough to raise the one edge of the sled/jig enough to allow removing the requisite amount of material from the back side of the deck (Composite - that's what they call it) board to provide the maximum amount of slope over the three or four inches of exposed "sill" I required.
Worked like a charm. I cut the result to fit up and under the Sliding Glass Door (Patio Door) sill and lay nicely upon and over the brick facing with it's pretty detailed "factory finish" side up and proud.
For the deck railing, I needed to slope both sides from the middle (I was using two-by material - Cull PT Lumber 50% off list). I added another low guide strip to match the smaller width of the 4-inch material and added a quarter-inch or so to the strip used for raising the jig for the sill (steeper bevel desired) and ran each of the railings through twice. Turning end - for end, with each pass, then taking a bit more off, repeated the procedure until I was pleased with the result.
Then, I ran each rail through the router a few times. First to create a "drip edge" slot on the underside of the rails (like they do on wooden window sills (or did), then using a round-over bit on all four edges.
Man, they feel great! - Look like something factory-made.
Anyone need P.T. Shavings?