I am building a tire swing this weekend using a trailer hub for my piviot. The arm is giong to consist of 2x2 tubing with 1/8" wall. My question is how should i weld the tubing to the hub. I am going to cut off and grind down the hub so that it is round. But i may leave some so that it will stick out into the tubing to give it some extra support. But my main concern is getting good penetration with the weld in the hub and not buring up the tubing. I was also thinking of making a strap that goes around the hub from the tubing all the way around to the other side.

Any welding or fabrication tips would be handy.

Also if you know exactly how to get the hub off the spindle that would be great too. There is a castle nut holding the hub on the spindle that has a cotter pin going through it. But no way to access the pin except from the top. Any ideas appreciated.

beval the edges on all the joints that must be welded with a grinder... .make sure the angle of the electode/gun is so that both sides get equal heat and your not just penetrating one side... crank it up as hot as you can get it (practice on scraps) without it blowing out the metal