How many plys?

I've decide to make a board and I need some help with plys.

I'm using 1.5mm hoop pine and I want a stiff board. I plan to make it a 40" drop deck with fairly aggressive concave and weigh about 65kg. Want to avoid having to glass it if possible because this is my first build. I was planing on using 8 plys of the stuff. I've tried looking this stuff up on SF but not many people use it, it appears to be used only buy aussies.

Thanks!