Tandem Skewers
Purchase quality skewers and make sure the fork and rear stays are parallel. I have bent solid axles on a tandem but never bent or snapped a hollow axle. This is because I replaced the cheap wheel set that came on my 1990 Burley Bongo with Phil Wood tandem hubs and Campi SS Skewers. The convoluted rewrite of the laws of physics for Skewers on disk brake bicycles has more to do with manufactures cheapening the parts to the point that they became dangerous. Skewers/Quick Releases have obviously been a mystery to many people.