Quote Originally Posted by CharlesJenkinson View Post
Apart from looking nice, I'm not convinced these types of bed frames, with massive members, need to be fully welded at the joints, from a stress point of view anyway - stitch welding would be perfectly adequate - having said that, the effect of inducing bending due to weld shrinkage is possibly only noticeable on smaller dimension square hollow section, less than 70mm say.
Charles Very true regards Stitch welding being plenty strong enough if done correctly but even larger dimension SHS will distort if the heat put into it is too great. Spreading the welds around and keeping the bead length down to a minimum is very much needed with any size material if distortion is to be kept to minimum.

I've just got my self a New 250A AC/DC Tig welder with pulse and I love it for just this reason as the heat is kept very isolated to small area. Fact I can weld thick Aluminium plate as well as thin Aliminium plate is lovely as well.