Back to the big trestle, here’s the current plan. I can’t do much while on travel, but it helps me to rehearse it mentally.
This starts with the as-is plywood on 4x4 posts which have been there maybe 10 years.
After removing some posts, and using a laminated cardstock template, the upper part of several hanger jigs will be screwed to the existing plywood. These jigs suspend an acrylic footer piece in space, up to which a few rocks are piled and mortar is formed for a pier.
The piers won’t look like this, but will follow the contour of the ground as needed. Once poured, the rest of the posts can be removed because the first jigs are holding up the plywood. (If not I’ll put in more temp posts). Then the rest of the hangers can be placed and their piers poured.
After that, the jigs and plywood can be removed. What should remain are the acrylic footers properly positioned in 3D space, with solid concrete supporting them.
After bents and the deck are made (with jigs & a big template), they’re to be assembled in the shop with stringers and braces on the existing foam assembly jig. The pedestal heights match the hanger jig lengths.
The three bent groups should install upon the footer pieces…
…and then the deck assembly will be set on those and screwed down.
Each bent has a 1" x 1/2" lower shim board which can be sanded (or re-made thicker) as needed to properly support the deck.
I’d rather not screw the bents down to the piers, but that’s an option. Another one is to make U-shaped acrylic pieces that glue to the footer pieces, and laterally lock each bent’s shim board in place.
At least, that’s the theory.
Cheers,
Cliff