I'm looking for magnets to attach door panels to my metal stand. What weight rating do people use for this? The panels will be 1/2 plywood and will be resting on the floor and I envision a magnet in each corner of the panel (roughly 2'x3' panels). The magnets are to hold them to the stand securely and to keep kids out. I'm debating between 12lb magnets and 26lb magnets. The 12lb magnets are basically fridge magnets and seem like they'd be weak, but amazon reviews on 26lb magnets say they're really hard to pull off.