HDO plywood information please?

[Mel Fulks]

MDO is a great product , but plywood with Canvas glued on and painted is great , just paint it. Canvas covered wood goes way back

[Ole Anderson]

MDO and HDO are good against water ONLY if the edges are well sealed.

John

Pretty sure DOT doesn't bother edge treating traffic signs.

[Ole Anderson]

HDO is a softwood product so not as strong as BB but better for exterior use.

I would have thought also, but from the industry guide: "Both high-density overlay plywood and medium density overlay plywood are kinds of hardwood in which a resin is soaked between the veneer layers. When it comes to the top veneer layer, it is an “A” grade of both sides and provides a smooth surface without voids."

Either way, it is really nice stuff to work with. No voids, just like BB.