A yellow pine frame will be heavier than the same frame made from WRC, but when compared to most off-the-shelf composite and rotomolded kayaks it will still be relatively light weight.

I don't coat entire frames now (just the plywood parts) although a coating will help keep the wood itself from absorbing water if you always get a lot of water inside. Yellow pine is so dense and resinous, I don't think it would absorb much water, and its going to be relatively durable anyway. Letting the kayak dry out between uses is good practice weather or not the materials used are considered rot-resistant.

: Yellow pine is heavy but I can't imagine it adds that much weight. It would
: still be an extremely light weight boat. Main thing is just how it would
: hold up. I was thinking of spraying the frames with a good sealer. Not
: sure what yet. Poly probably. Of course I know that pin holes happen and
: water will get in sooner or latter. But I also think it wouldn't be too
: hard to replace a section of frame either. These boats seem easiest to
: repair to me if needed.

: As for scarfing, I was thinking or making a jig to cut the scarf. But it
: still will take a fair amount of time to rip, trip and scarf. Even with a
: all the right tools.