I agree. But small aluminum tubing with specialty o ring seals? I couldn't see trying to screw it up when I knew I could form it. Not pretty , but it'll work.That's a lot of work. Nice job.
On the bend you had to hand form.....
I've never tried it but, it's how they used to make custom headers. It was called sand bending or something like that. You fill the tube with dry sand and cap the ends, leaving a tiny hole in each end. Hit the tube with a rosebud and you can make super tight radius multi axis bends without kinking.
I've always wanted to try it.