A few weeks ago, I complete my new, re-designed
rain fly support system. The support system consisted of two vertical 4x4 posts and a horizontal 25-foot cross piece running from post to post. I built the cross piece using doubled-up 1x8s, face-bolted together. I staggered the joints so that they were 4 feet apart.
The finished board was 1-1/2" thick x 7-1/4" tall x 300" long (that is, 25'). It was a ribbon of a board, and when you picked up one end the tried to get it to stand on edge, it would inevitably twist and turn and lay down flat at the other end. I was a little concerned about this behavior because I needed the board to stand on edge once I fastened it to the posts.
When I first installed the cross piece, it had a nice, gentle twist to the right. It sort of reminded me of the pleasant lines taken by wooden strakes on a rowboat. But I didn't want this thing to glide through water, I wanted it to stand up on edge. My good friend, Tom, who helped me put the board in place said, "You'll never get the twist out of that thing." Well, maybe, but I was still gonna try my best.
I attached a few ropes at different locations on the board and pulled and tugged as needed to get the board to stand up on edge. I finally got it pretty close and staked the ropes in place.
The board would hold its position for about a day before slowly sagging and twisting in a new direction. So I'd pull and tug and stake out the ropes again, only to have the board twist at yet another place a day or so later. This cat-and-mouse game continued for awhile. Then, a few days ago, I was trying to straighten out a particularly nasty twist and heard a "crack!" I peaked under the rain fly and saw exactly what I didn't want to see. One of the joints had cracked. And with that bad joint, there was no way the board would handle any sort of a snow load this winter.
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Failed joint in the 25-foot cross piece |
Well, turns out Tom was right. I couldn't get that thing straightened out. I'm leaving the board in place for now, since it's still fine during the summer when there's no snow. The rain fly has quite a sag, but it's still sheds rain just fine, and it offers much needed shade on these hot summer days.
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Twisted cross piece and saggy rain fly |
Okay, okay, so let me be the first to say it: FAIL! I guess it's back to the drawing board (and I already have some ideas for Version 3.0).