HELP: How to create a radius around a circular penetration on a curved surface?

Hi there,

I’m trying to create a radius that follows a circular penetration on a curved surface… Is this possible? Images below of what I am trying to create, however nothing seems to work…

Any help or suggestions would be greatly appreciated!!


I’m no expert, but I found this very helpful, especially Jeff Hammonds video: Can this be done in SU? • sketchUcation • 1

The Round Corner and (newer) FredoCorner extensions by @Fredo6 and hosted on SketchUcation can add a fillet to the junction between the two intersecting cylinders.

I would love to see an example of that- I’ve used that plugin only to do the most basic of roundovers or chamfers

Here is an example. Depending on the radius and numbers of segments of the intersecting cylinders, the RoundCorner result can have some irregularities that require manual cleanup. In this example, there were four places where I needed to do cleanup.

Here is the initial shape without a fillet. (I created the shape by drawing two circles and Push-Pulling them into depth. Then I selected the surfaces of the resulting two 24-segment cylinders, and used Intersect With Selection to produce the junction. Then I deleted the unwanted part of the smaller horizontal cylinder that was inside the larger vertical cylinder, along with the portion of the larger cylinder’s surface that was within the smaller cylinder.)

The somewhat jagged junction, inherent in SketchUp’s representation of curves, is an indication that the automatic generation of the fillet may have trouble.

Here is the result of RoundCorner, with a smallish fillet. (A larger fillet would magnify the troubles.)

You can see two places with odd shading that are the intersecting faces added by RoundCorner. Two identical cases are on the other side of the object.

In the third image I have spent a minute to delete some of the auto-generated edges and drawn in new edges to heal the object; it is reported as Solid by SketchUp. I have left the new edges “hard” (not smoothed and softened) to make them more visible:

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thanks very much for that, I’ve been wrestling with it myself, with marginal success. I just realized that I had been leaving the faces inside the cylinders, and that prevented the tool from working as expected. Thanks again!

Thanks! That helps a lot!!!

Kind regards