Oh oh oh! I call this one, coming right up.
Here it is!
Now I have a question to seasoned part authors... When building the V-cut tubes below, it seemed to me that I needed inexisting primitives, the complementary of 1-8cyls(2) in 1-4cyls(2). I managed to create that using overlapped 1-4cyls and cyls2... could I have done better or do we really need new primitives?
Awefully sorry! I won't object if you submit a better version than mine!
Well, I'm honestly not sure that a better version is possible given the available primitives.
I was just using normal quads/condlines to connect the tube to the slope to avoid the overlap, but I think your solution is better.