The Sisu 1A Maximum Airframe Load Factors: + 6 G, - 4.6 G
The Gross weight: 730 lb

And the wings are probably a lot higher aspect ratio than the ones your
considering. Long skiny/thin wings need stronger spars than short fat 'uns.

Just a WAG your probably looking at around 30,000 ft/lbs at the spar root for a
cantilevered wing? For a 6 inch deep spar that's around 33 of those little
hinge points - IIRC the numbers from the earlier thread correctly.

Of course getting 33 of them coplanar so they fold might take a bit of
length......

Then again with the ever reducing cost of CNC machine work you just might
consider one-of-a-kind units in a larger size.

I also remember seeing a post here a year or 2 ago about some extruded
graphite/carbon fiber hinges. I have no idea if they are even as strong as
aluminum (kind of doubt it) ones but it might be worth a quick internet search.