1/16 wall thickness is really pushing it if you are going gas. 1/8" tube is enough, but I would be afraid of the heat from the burner. I made my rig out of 1/8 x 1 1/2" andgle and it is more than enough. and i do up to 25 gal batches. If it were me, I would go with 10ga square tube by 1". It will be more than strong enough, and still reasonable in price. Doesn't have to be over kill.