I'm having a problem combining object and achieving a fillet. I have no doubt the problem is with me, but I'm stuck as to how to resolve it.

I'm creating two shapes from the following outlines:






I'm creating the "wheel" from this curve (highlighted)



Sweeping it



Then lofting the following closed curves to create the "body"


I end up with these two shapes. So far so good. Ideally what I want is a nice smooth transition between the two shapes. Is there a better way to approach this?


If I boolean union them, and try the fillet it either doesn't work, or at 0.01, it "works" but there's all sorts of artifacts. I've uploaded the 3dm file if anyone wants to take a look at what I'm doing wrong. Thanks! The final two shapes are named "body-wheel proto".

Hi Jim,

It has been my experience that lofting works best when using the fewest profiles as possible - and then moving those profiles small increments to tweak the shape. I suspect that you could remove a number of those profiles and smooth out the result.

Hi Jim - for the wheel part I'd recommend using Revolve instead of sweep - anything that looks like a 360 degree turned thing is usually better done with revolve, it makes more precise geometry.

Most likely the problem is that the closed sweep has just a very tiny crease in it where at its seam point where it closes up, and filleting does not like little tangent deviations like that.

But also a different thing you can do in this case is go to into the right-side view and just rotate the wheel left by 90 degrees (select it and grab the little rotate grip and drag to the left 90 degrees).

That will move that seam area out of the zone that you are filleting so it won't really matter how smooth it is or not at that point.

It's also just a helpful thing in general to have fewer edges running into each other when doing a fillet.

So after rotation, the wheel will look like this (note seam edge is towards the front now):



Now you can do a boolean union and then select these edges:



And now those will fillet up to a radius of 0.5 or so:



You won't be able to go much larger than that because that's about all that will fit in this spot here:



But for things that look like they're incorporating some kind of circular shape in one direction, try using Revolve instead of Sweep and that will probably help make a bit higher quality geometry with a 100% smooth area where the surface closes.

- Michael

Thanks a lot for the help guys!