Originally Posted by Jiggyjay
Built an uber simple fishing frame for my raft and I'm currently using 1 inch conduit tubing. I'm thinking of now using square tubing so that I can easily install rails to mount accessories on. Any problems I might run into using square tubing?
Shape factors: Square or rectangular tubing will be stressed across the tension and compression face disproportionately since the web is incapable of uniform distribution. A round profile will not share the same issue but will be more flexible for a similar mass, hence the 17% upfactors for round sections bending linearly. Round sections also feature hyperbolic welds which are stronger about multiple axis.