les,
My microsoft streets program calculated the shortest or quickest, rather, way to Bandon being, through Hood River to Portland via I-84... Then going down to Eugene via I-5... a few miles before Eugene get off in Mckenzie on the Westbound Beltline Highway till it becomes Beltline Road... Then turn Right at SR 126  or Florence-Eugene Hwy... Looks like a windy one... Thats WINE-dee.... 

... Then in Florence its the 101, Oregon Coast Hwy all the way to Bandon... ... ... Don't say you never got a help from a windsurfer! 

 Total Distance 1,019 miles...
PS... You could go through Bend from about Caldwell Id... via SR 20... But the distance isn't that much shorter and the drive would be SLOW!!! Good Luck... BTW.... What's in Bandon?