How do I round corners made by curved faces and curved lines?

Hi everybody, very much hoping someone can help me with my model of a ring. I’d like to round all the corners and so far have not found the way to do it.
Maybe my buildup of the ring is incorrect - having no experience with 3d modeling before I need advice how to approach this from a 2d flat image. Thanks!

R Tjitske onewng.skp (1.6 MB)

It would be much easier to help you if we could see your SketchUp model. Could you upload the SKP file please?

Sorry! My first post here - was looking for the upload button :slight_smile:

Sventh button from the left in the row across the top of the message box. Just to the right of </>.

R Tjitske onewng.skp (1.6 MB)

And the 2d which I started with. R Tjitske onewng 2d.skp (80.0 KB)

first you’ll need to do some cleanup of some edges like the ones shown highlighted here. there are doubled edges but erasing them and drawing in single edges should take care of it.

Something like this:

After cleaning up the model, I would use Fredo’s Round Corners to round the edges. Work on a scaled up copy to avoid creating very short edges which would result in holes.

Are planning to have this printed? You might find it isn’t worth the trouble to round the edges. It might be easier to round them by hand when you get the final product.

Thank you for your fast reply! I did think it had something to do with the messy faces on the outside because Fredo’s round corners had a gazillion, well not quite, but many overlaps which I gave up on.

I do want to have the ring printed and am worried that the actual scale will be a nightmare to round by hand - 1 mm wires…and not quite organic looking.

Is there a less messy way of extruding and/or bending the total face as in the 2d? I noticed the inside face of the 3d ring isn’t messy.

This! Unless your print is fairly large, or you are rounding a LOT, it is far easier to run sandpaper over corners to round them. a small rounded corner and a “sharp” corner often print the same. Unless you are going to round the equivalent of 3x the print layer width, it will be better to round by hand.

You might find it easier if you started over with cleaner geometry. You’ll need to do a lot of cleanup to get the component to be solid for 3D printing anyway. I don’t see that there’ll be a good return on your investment of time rounding over all those edges. It’ll take less time to round over the edges on the final ring and you’ll be able to create a more organic looking shape, too.

Thank you both for the advice - the printing is new for me too!

How do I start over with a cleaner geometry? As in redraw the shape?

I pulled up your model, and here is my recommendation.

You might try the extension “SUDb” by Thom Thom (came out December 15, 2015). It allows you to work in a “rough” shape, sharp corners, but actually you are making changes to a model that is very organic. How organic it is you decide, and then switch back. (You would also need the extension “Quadface Tools”.)

There are a couple of videos on YouTube that explain how it works: first one, a spoon--; the second is a four part Tatlin sofa SketchUp Subdivision Modeling, part 1 is at Actually, there are four more parts.

But, I cheered when I saw it because Thom Thom’s tools make organic modeling, even if you’re just rounding off corners, so much easier.

I have a part of a model that I’ve been working on for three years, and I’m going back to deal with one particular part because with SUBd it will turn out so much better (and it’s pretty good right now).

I should mention that I have used Thom Thom’s Vertex Tools and Quadface Tools from the very beginning.

Thank you for this! I did install both extensions thinking it would do the trick, also for future projects, but was completely unsure how to use them. Will try that now.