Question on water "resistant" LUAN

[Randy]

Would that work for the pirogue project....?
or the oaksheets?

[gerald]

At least 95% of all exterior grade plywoods are made with waterproof glue. In most cases the same glue as used in marine plywoods. Luan is probably the best of several good exterior grade plywoods to use if you are not going to use marine plywood. Fir is not good because it checks badly. Oak and many other plywoods are simply too heavy. They will work but the boat will be heavy. Luan is also heavy compared to okoume marine plywood. In all the years I've built boats with a variety of plywoods I've only been burned once by bad plywood. I thought it was ok, still not sure what went wrong, but I had to replace that boat. I'm only going to use marine grade plywood from now on, but for many home builders luan is the better choice for an inexpensive boat.

You can use the boil test on the plywood in question to be sure. Take some small pieces, boil them, let cool, boil again, let cool, boil again--and let cool overnight-in the water. Then let dry thoroughly. If the pieces survive, the plywood is ok. In most cases the wood will deteriorate before the glue line will. This will be the case with fir plywood--and most of the plywoods that were peeled off a log rather than sliced.

[Randy]

looks like luan then, I won't have a ton invested if it turns out to be fancy firewood, before fiber glassing.