Howard Acheson
Epoxy does not need good fitting joints. Just roughly scrap out the old adhesive. Use slow set, two part epoxy. Speed up the reaction with an infrared heat lamp or a hair drying--or just let it set up overnight. Keep it in a warm spot. All the chair repairs we did epoxy adhesive was used.

In our shop, we used epoxy on all new chair joints. It held up the best--we never had a failure. Failures in chairs--or stools for that matter--are very dangerous so you want to do everything you can to prevent them.

The fact that the joint(s) failed is an indication that the adhesive failed. Any PVA and most especially any hide glue is guaranteed to ultimately fail.