Get your thinking cap on.
I need to make 16 little box-like sheaths that will act as footings for vertical 1x4s. Each sheath will be fastened to a 22"-long ski-like base. To help you visualize this, the upright 1x4s form the two sides of eight H-shaped stands (39" tall x 25" wide). The stands will fit into the footings, which will in turn prevent the stands from tipping over front-to-back under the light load they will bear. In the photo, there's a short length of 1x4 fitted into a mock-up of a footing. The footing is 5" tall. Its sides are 3-1/2" wide and its ends are 1-3/4" wide (inside dimensions are 3/4" x 3-1/2"). The footing is intended to fit closely around the 1x4. The plan is that I'll set two feet on the floor and insert the sides of an H-shaped stand down into them.
footing mock-up.jpg
So much for plans. I was so excited about figuring out the configuration of this contraption that I gave no thought to how I would join the parts of the footings. I designed the parts to be made from 1/2-inch plywood, and I eagerly cut all 80 (!) parts last night. I used a pre-finished sheet of 1/2" ply left over from cabinets I'm building.
Once I had all the parts cut, I was chagrinned to see that assembling them into boxes looks impossible, or impractical at best.
Two problems:
1) I don't know if the pre-finished plywood will take glue. I suspect it won't.
2) These things have no joinery elements; they just fit together theoretically on paper. It looks like a difficult glue-up to get them to form a 5"-tall box with smooth sides. See the gaps in the photo.
One option I'm considering is clamping the box parts together and joining them with #6 screws (no glue), and then screwing them to the base up from the bottom. That might be the most practical way to use all these parts. But it will be a wobbly, fussy procedure.
While I slept on it, I thought about making the footing parts again, but this time with 1/2 MDF, and adding rabbets to the vertical sides of the end parts to register the side parts into them and make it more stable for glue-up.
If any of this makes sense, here's where you come in. How would you make these footings?