Terry: Re fasteners for intersections of 1 X 2's: Use 1 1/4 inch # 10 or 12 SS pan head sheet metal screws, set into counterbores on the inside and run into pilot holes in the outer layer. You might want to put SS washers under the heads to distribute stress on the inner member. Cheap and in stock at MSC and other sources. Ken Zastrow the copper heron forge