There are lots of sea kayak designs out there, even some free ones, but
white water boats seem to be difficult to find.

I'm wanting to build two playboats for use in non-rocky rivers, mostly
park and play spots. One will need to be similar in concept and size to
the Jackson Shooting Star (a boat capable of radical play moves and loops
for a 35-40 kg or 75-90 pound paddler). The other will need to be bigger, as
I have nearly forty years longer of beer and pies than my daughter, and
probably don't want to be quite so radical...

As I haven't paddled playboats much myself, I don't have enough idea of what
works to design from scratch, and wondered if anyone has any designs out there
I could use as a starting point. Mike Allen's designs look wonderful, but are
not published as plans, as far as I know, and I'm probably wanting to build in
strip rather than ply. There are a few surf boats with maybe enough info to
build, but they are really for a different purpose (I've read a long article
somewhere as to why river playboats are not really good surf boats, and the
converse must apply...)

Anyone got any Kayak Foundry or Free!Ship files they might share ?

Andy