I have two ducts : one with a square section, the other being a round pipe.
The square duct has an inner section 1×1 = 1 m²
The round pipe has an I.D. of 1128.38 mm giving the exact same cross section (π × r² = 1 m²)
Their thickness and outer diameter is rather irrelevant to the problem here, but their walls are 10 mm thick. The two ducts are located 1 meter apart and are aligned on a common axis.
How can I connect or join in Shapr3D the two ducts with a coupler of gradually changing geometry keeping the same constant cross-section? Of course the coupler needs to be tangent to either duct in each connection point.
In SketchUp for example, there is the “From Contrours” tool that draws a surface between two distant contours (lines or curves) like a stretched sheet. It’s quite perfectible but in a mesh 3D software one can always modify manually the triangles afterward.
In Shapr3D, I do not see any equivalent tool. I tried to move the base of a cylinder away from the face of a (bigger) cube but it acts in a way that the resulting coupler (see the yellow part in the second picture below) has walls that are not tangent to the walls of the square duct. It looks a bit like the mountain in Close Encounters of the Third Kind
You need to make your objects solid (without a hole). Offset faces inwards until no hole. Then Loft the faces of the two parts. Then Union the 3 pieces together and finally Shell to get the thickness. That will give you this:
if you want the ends to be tangent, you’d need the Parametric Beta version. In that you are able to open the history step created for the Loft and can change the continuity level at the start end the end (we’ll create a better UX for this soon, but that’s the only option right now)
for the Loft to work, you’d need both sides to have convex faces (they should be a cube and a cylinder) or if that’s impractical, you could create sketches dedicated for this to which you project the body edges and use the outer ones
you can then Union the bodies together and use Shell (selecting both end faces) to make the end result hollow again
Is this something like what you’d want to achieve?
LOFT. Then hollow with SHELL. Of course! Thank you very much guys
The use of the parametric function is also very interesting, thank you also for this 2nd advice
