Love the notes and the priority of the project :)
What's missing from the site header picture are the huge chunks of cement I use to hold the boards in place. We had this old, awful cement walkway in our backyard that my dad and I destroyed with some hard work and a sledgehammer. We tossed the chunks in a riding mower trailer and lugged them out to a corner of my yard in the woods. When we built the rink, we decided to re-use, and now lug 6-7 of these huge, heavy (50lb+) chunks out to the rink. We put them right up against the boards and they don't move a bit because one of the best benefits of the court is that it's flat. I still have some slope in mine...my 40x56 install has about 4" in the shallow end (near mid-court) and 8" in my deep end (along one of the fences, beyond the baseline of the court if you will). With only 4-8" of water, there isn't a TON of water pressure so you won't need as much bracing. I think your sandbag idea is either great or overkill...neither of which will cause you problems :)
Note: if $ aligns, I am planning on moving to Nicerink boards/brackets this year some time, mainly because the storage of my 2x12's is a pain. The NR boards stack nicely and I have a ton of leftover brackets from my installs, but we'll see. I bought some large "real" rink board corners so I'm planning on totally redoing my rink, so we'll see where I land. I have been brainstorming with my dad extensively on this "next gen" build, and I'm hoping to either build, or have built, some sort of hard-surface-bracing mechanism. Basically some sort of sealed pipe that you'd cement into the ground, but that you could (a) drop a piece of rebar into in the winter and (b) cap in the summer for rollerblading. I'll keep you posted.
I'm Joe from Backyard-Hockey.com and EliteRinks.com.
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