Of course a round tube is possible here too w/o support. But I decided to design it the way it is, because I thought it would be more air tight.
The printer prints straight lines now, otherwise (with a round tube) the tube will get much more „single lines“ and will be much more affected fr air leaks.
It is no problem to design a round tube. If you want me to do it, just tell me. But imho it isn‘t worth it.