@dave r said: Doing what I described, extend the edge of the step out a bit beyond the end. If using Follow Me, extend both ends. Draw the round over profile at 90° to the extended line. [attachment=2:2bsn6w8o]<!-- ia2 -->Screenshot - 9_14_2018 , 7_09_26 AM.png<!-- ia2 -->[/attachment:2bsn6w8o] Extrude the profile. If you use Follow Me, preselect the path including the extended edges on each end, get the tool, click on the profile face. Since the run is straight, you could use Push/Pull instead. For Push/Pull you don't need the extended edges. [attachment=1:2bsn6w8o]<!-- ia1 -->Screenshot - 9_14_2018 , 7_10_59 AM.png<!-- ia1 -->[/attachment:2bsn6w8o] Select all of the geometry, right click and choose Intersect Faces>With Selected. Then erase the waste and correct the face orientation on the roundover as needed. [attachment=0:2bsn6w8o]<!-- ia0 -->Screenshot - 9_14_2018 , 7_11_50 AM.png<!-- ia0 -->[/attachment:2bsn6w8o] This is similar to what Liam shows but avoids the need to move the roundover into place and prevents possible errors in placement. Nice!

Here's a nice tutorial/video from Dave about this topic... https://www.finewoodworking.com/2017/12/20/sketchup-details-transitioning-from-square-to-round