laminating two sheets of plywood for a desk top
I am presently in the middle of making a new desk for my home office. It will be approximately 6' x 3' in overall dimension. There will be two tapered legs on the left and on the right will be a three drawer pedestal. I have the legs, the apron and the pedestal almost finished and am now thinking about the top.
I would like a sturdy, thick top and am considering laminating two pieces of plywood together: a 3/4" sheet with oak or walnut ply on the top, and beneath that a 1/2" sheet to bring up the top's thickness to about 1-1/4". I'd square off the top and put a nice hardwood edging around it. I don't have access to a planer or jointer so nice plywood is my only solution for a suitable top.
My question concerns laminating the two sheets.
1. Should I glue them or screw them together? Will I have a problem with different expansion/contraction rates on the two pieces -- I guess there's no guarantee they'd have identical expansion properties, though they should be similar.
2. How's the best way to glue and clamp two 6x3 sheets together? Are there clamps that can reach the center of the tabletop?
3. Is this just a bad idea? Do you have a better one? I suppose I could live with just a 3/4" thick top, but it seems kind of skimpy.
Any thoughts or help would be greatly appreciated.