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EPOXYWORKS Search for "A Quick Architectural Fix" If you don't want to buy thickener you can use fine sawdust mixed with the epoxy. Be sure to let the door dry before applying the epoxy. About every 1/4 inch drill 1/8 inch diameter holes through the rotten wood into the good wood, then pore the epoxy in. It will soak into the surrounding wood and make it quite strong. You don't need the "wood restoration" epoxy you see advertised. West system 105 resin works very well. Good luck.