Surface Transition Question

I’m designing this product and can’t quite get the surface I’m looking for in the back. I’d like to diminish the continuing fillet curvature on the back face–to reduce the edginess and make the back surface as round as possible, as close as possible to the front face. I don’t know if this is even possible, given a retangle>ellipse loft. Any advice?

The result I have now is acceptable, although the curvature at the front needs to be bulged out a little more…

I’m in Solidworks, but I have access to Alias and Rhino if those might be better for this surface.

Thanks in advance for any advice.


Well you did it with one loft feature from the look of it so you might get some more control by dividing it into patches that you can control. You are also lofting to the corner fillets and those are a little harder to sketch. Do you have an image of how you want the transition.

MasterBlaster’s idea of splitting it up could solve it, but SW isn’t always the best at truly continuous curvature between features so I might try a little more with one loft first.

I’d try either adding another sketch profile or just moving the circle closer to the front (and making it bigger). The new sketch profile could be another circle or a sort of rounded rectangle, except with arcs for sides. Make sure this new sketch has the same number of segments as your front sketch. If you are unsure of the shape and size, a trick I use is to make a plane after the loft where you want the sketch. Make a sketch on that plane and do an intersection curve to get the current profile at that point. Then delete all the sketch relations and fix all the lines (optional) and exit the sketch. Since you deleted all the relations you can now move this sketch (and the plane) before the loft and use it as a reference as you draw the new profile. Just make it a little rounder than the reference.

I’d go to Alias, use 1 circle with maybe 12 control points. Then use a circle (also 12 points or more) that you move the points around to achieve the rect+fillets shape. That will give you a continuous smooth, soft rectangular shape, that will skin easily to the other circle. then just adjust the CVs to get the funnel shape you want.