Use 1.0mm. It's almost as thick, easier to bend and probably less expensive than 1.5mm. Just make sure it's WBP (Marine) Birch ply and not some cruddy "indoor" variety.
Dave M

Edited By Dave Milbourn on 26/08/2014 14:34:11

Edited By Dave Milbourn on 26/08/2014 14:34:58

You mean like this marine ply isn't? **LINK** Confusing, isn't it?
I think you'll find it's true that, while all marine ply is water-and-boil-proof, not all plywood described or held out for sale as WBP is marine ply. You clearly were aware of that already, but I thought I'd clarify the matter in case I had confused anyone else.
For making model boats either type will do the job well, but it's not necessary to buy true marine ply if you glue and waterproof the model properly. It's vastly more expensive and more difficult to work than WBP. I personally use a lot of Liteply, which isn't even WBP, and I've had no problems with it delaminating or soaking up water.

DM

Possibly…………….. but Ashley isn't giving away the secret any time soon.

Personally I reckon that a good slopping of Z-Poxy Finishing Resin will make anything waterproof – even toast. It just might be a bit of a b****r to sand smooth.

DM

I've heard it said that the East Germans made cars out of cardboard (the Trabant) and that was deliberate ploy so that in times of emergency people could bite a bit off the wing and thus avoid starvation. Especially tasty if dipped in Vodka!

Colin

Naughty stair! NOW!

Dave M