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Somewhere in Kenya.... a village is missing its idiot!

Alaskans for Gobble Warming

A hobbyist woodworker would need a welder and  a hammer and some steel bar flat stock to make that, but s/he most definitely could pull it off.

looks like a 1/4-20 in there. I think that would be a tad small. I'd go with a 3/8-16 and employ a larger surface area for the nut's washer. Plus you wouldn't need to use the little ball nut that they use you could just use a chisel or a router to make a flat spot and use a bit of 1/4" thick ( or thicker) flat stock steel for a washer and use a hex nut.

I'd also use more screws than they did to lock the thing in place plus I'd cast it in place with epoxy to minimize movement.

Still without stretchers ~ ~ ~~   No amount of steel is going to resist flexing completely.  This means the joint will work and over time will show signs of separation and wobble. Possibly that right angle grain structure might  crack.  How much time?  I dunno.