I have literally spent nights lying awake thinking how best to attach the bindings.
In the end I decided to simply drill a hole through the polycarb and put a bolt through.
The first board I did the same thing, and it was pretty robust. Then I recessed the bolt head and somewhat unsurprisingly the board cracked at the bolt hole the very next session.
From what I know about polycarb and acrylic's properties, they are both considered notch-sensitive materials. I don't know if an insert will cause a crack but I suspect so. In any case the sheet is only 5mm thick and doesn't allow much room for an insert to anchor.
Wiping out with bindings can put a tremendous amount of force through the board. Something like a faceplant at 20mph is enough to bruise my ankles (and face
) and rip the laminate loose from the base sheet. I wanted this board to be able to withstand that level of punishment.
In any case, the bolts I use are wide flat head stainless steel M6 bolts. I grind the heads down to 1mm to minimise drag as much as possible.
I'm sure the bolt heads cause some drag. But I can live with it.