The main issue I had with plascore I purchased it blindly and did not know it was available with or without a resin barrier. And, of course, I gor the one without because they asked me if I was bagging the work and my table was too small to bag without xtra seams so I did not. And the resin usage was sickening.
Barring that, it is nice for soles, or perhaps a flat bottom, but hullsides, no. It is lower cost for each unit thickness, so if you want a full inch sole or bottom; it is a good choice.
The stuff is used for flat bottom drift boats and can certainly be used where rigidity is less important. A drift boat is relatively narrow bottom and the stuff makes a walkable sole laid up well.
But for hullsides, it will need a layer of glass to go on the jig or in the jig, too flimsy alone. And the question then is how much glass. And why? If you build hullsides at a full inch, it would not be a 15' boat. So, alternative core for the 15'er is foam. But, I hate to break it to you, foam will take quite a bit longer to build because each piece needs to be glassed before it goes into the jig. So, unlike ply, you cutout each piece and glass it and then stitch versus ply where you cut it all, stitch it all, glass the whole thing. After preglassing the foam; you stitch it all and then glass the other side and tab or glass the opposing side more. I have the plans for a stitch n glue foam dinghy and am hoping to use 6 oz on the inside per panel, glass the outside in 12 oz and then flip it and tab the inside. Harder than ply no matter the tack.
And a lot of people think foam is cheaper, but it generally uses more resin and cloth and thus is not.
For small custom builds, plywood is still the magic.
