Hello Forum, I’m working on some custom stones. Radial corner units, they slope and curve around a 2006mm radius corner. What is the best method to maintain the radius with a sloping curve ? tia 
(screenshot and sample file attached)
Maintain Curve Radius.3dm (464.5 KB)
Hello- the radius should be constant in Top if you make the arc flat first and then adjust the control points vertically to get the slope (it will no longer be an arc)
-Pascal
That would be the Helix command. It will maintain the radius (when viewed from top) and a maintain a constant slope. You would want a helix with 0.25 turns.
Helix.3dm (451.1 KB)
I used sweep1 using the edge of the trimmed surface (1/4 cylinder) to make the green surface. Oddly, the edge as a rail made a nicer surface than using the helix curve.
Jim,
That works if adjacent sections continue to rise, or continuity is positional only. But if the adjacent sections are flat and a smooth continuation is wanted a blend will be preferable.
Unfortunately we don’t know the OP’s intent yet…
Regards
Jeremy
If level tangency is needed, I would change degree on the flat arc to 3 and move two points up or down to the level required.
-Pascal
@pascal @jeremy5 @jim thanks all for the suggestions, appreciated. The intent is for fabrication of solid granite blocks as per the screenshot attached. I’m unsure at this stage which factory we will be using so these could be CNC machined, or shaped in the more traditional method by hand. Most stone manufacturers working with stones this size work to a +/- 3mm tolerance anyways. @jim I never even considered using the helix 
.
