GW, you might try sealing the circumference of the joint and covering the exposed screws with silicone bathtub seal (RTV) when it is exposed and dry. The stuff holds up well in the weather and will peel off pretty easy when you want to disassemble.

If this idea makes no sense, it's Brettski's fault for getting me all excited.

"Live like you'll die tomorrow, but manage your grass like you'll live forever."
-S. M. Stirling
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