Here you can see my unprofessional try to make the round profiles for the front-intake.
I hammered 2" wide sheet metal around my tent pole with a rubber hammer, and it worked!
Then I added curvature with the shrinker on both sides, and atfterwards just one side to get the desired curvature in both directions
I need to smooth them out, guess I'll take the planishing hammer with low pressure for smoothing, but for the first try it looks pretty good!
Thanks for watching!