I've been spending WAY too much time making the bloody sheet-metal brackets for the "hip" joints.  The first three (red in the photos and videos of the prototype) are made from aluminum (aluminium for the UK) 0.025 " thick.  There I go again, being an American chauvinist ... uh,  that's 0.64 mm for all you civilized folk out there.

My procedure is to print out the flat pattern, glue it to the metal, then epoxy the metal to thin plywood, then cut out the flat pattern on my scroll saw.   ... drill holes, then bend using my cobbled-together brake.  This is too thin.  they bend and break and are very difficult.   Here is a picture of some of the remains.

It took six tries to get three functional brackets.  Too much..  Adding strength to the pattern and getting thicker metal.