IKEA Roger chair repair

IKEA Roger chairs have a specific failure mode. The bit of plastic between the bolt that holds a leg on and the seat frame tends to break. If you've ever found half of a black semicircle of plastic under a suddenly-wobblier chair, then that's what happened.

Print in strong material with 100% infill. Ream out the hole with a 1/4 drill if necessary. Add a washer (12 mm or 1/2") for better results. Print additional while you're at it. They break a lot.