The
tiller should be 3/4" thick. I'd go with at least one strong, fairly stiff
wood in your laminate...at 3/4" thick, the
tiller can be a bit floppy under load if you use a
wood that is not stiff enough. I sailed PocketShip #1 and found her 3/4"
tiller to be a bit too compliant for my tastes.
My
tiller is made out of solid 1" thick ash, milled to 3/4" where just where it slips into the rudder. It doesn't deform under load, but of course it isn't as attractive as the laminated
tiller you are hoping to build.
Good Luck!