Last year was my first year with a backyard rink. It went well for the most part, but the one issue I had was some bowing in the deep end. I used 1/2" OSB sheathing. It was pretty flimsy, especially combined with the 1x2x24" stakes I originally used.
What type of plywood is strong enough to help resist bowing? I also want to use a product durable enough to withstand pucks and bodies slamming into it. The deep end boards will be framed in 4x4' sections. I'll be reinforcing the deep end with angle braces every couple of feet.