I'm an old dog trying to learn a new trick. I've always used L girder construction now for my garage sized project I want to go with dominoes. I plan on using 3/4 birch ripped into 3" strips for the frame and legs, but I wonder about using butt joints with screws or nails going into the edge of the plywood. For some reason it seems weak, even if I reinforced it with wood glue where possible.

Am I missing something obvious, or am I worrying needlessly? Also what size screws work best in this case, or can I just use me nail gun and glue?