I thought it had to be flush all the way around...but then it's welding, so you can fill in the "smile" of the end there. Or not. It is steel, after all, and it's not that's going to be taking a lot of stress.

Winter don't skeer me. My mom knitted me a beautiful tricolor scarf to wear while flying! In fact, I like it when it gets (Alabama) cold. The air is a lot smoother. Of course I'm a nut and went flying a couple winters ago when it was 12 degrees! It's all just mittens and bundling up. Of course one can't have any exposed skin, but other than that it's all good.