From Longman Dictionary of Contemporary Englishreinvent the wheelreinvent the wheelinformalWASTE something to waste time trying to find a way to do something when someone else has already discovered the best way to do it → reinvent
Examples from the Corpus
reinvent the wheel• He had set out to reinvent the wheel; actually he wound up inventing it.• Without mentors we have to reinvent the wheel each new generation.• Learning by discovery doesn't mean reinventing the wheel each time you need to move the wagon.• I mean, why reinvent the wheel if it rolls? 