I used a #10 screen from McMaster Carr (I am a little upset with McMaster - they air shipped the screen - that is another story....). I spot welded (with my MIG welder) the screen to the back of the sheet metal. The framework is 14 gauge with a stiffener at the bottom. With the stiffener, this is about the right thickness to keep it from being too heavy. The customer is happy - that is what is important. May consider a different method of attaching the screen next time.