The arch bearing grape plants in our garden was leaning forward about 10 to 12 degrees. When my-son-in-law, Mike, built it, he used regular pine 2x4s on the four corner posts. He cemented these into the ground. However, the bottoms had rotted badly within the cement.
To straighten up the arch, I cut an eight foot 4 inch board in half. Melanie held the 3 foot spirit level against the front side of the arch to keep the arch straight up, while I marked the board on either end. These I trimmed off with my power saw.
Then while she continued to use the level to keep the arch straight upright, I used my power drill to screw in 1 3/4 inch number 8 power pro exterior wood screws -- first one screw on either end. And then I screwed in a second screw on either end to make it secure. I followed the same procedure, fastening a board to the other side. Now the arch is straight up.
Next I will cement in the bottom of the four posts so that the arch is permanently straight upright.
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