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Canvas chair piece
by eagleapex, published
We bought a folding chair a lot like this once http://i.imgur.com/LENPj.jpg about 3 years ago. It has been faithful, but broke last week.
Fixed it. This part is one of the junctions in the rear of the chair. The black, broken piece also pictured.
Printed at Hive76
You can adjust the part thickness to make it stronger, or change the dimensions.
I printed mine in PLA with 2 perimeters and 30% rectilinear infill and it holds up my [too much] pounds.