crossbeams or iako are very stiff and strong and avoid some of the
difficulty of constructing a solid laminated beam. In this case for my
Wa'apa, I used 19mm (3/4") timber top and bottom with spacer blocks to
hold them apart. It would be okay to reduce the timber thickness to
15mm (5/8"). Draw the shape of the beam on a flat surface or put down
some polytarp first to keep the glue off of your surface. Screw a
series of blocks along the line to which you will clamp the first
member. Glue and clamp the spacer blocks to the first member.
Glue and clamp the second member to the spacer blocks.
Glue and nail 4 or 6mm (3/16" or 1/4") plywood to the first side.
Bore a hole to take the hardwood dowel at the outer end.