Strange result with Sweep modifier with 3.6 (did not occur with 3.5)

[tinybot]

For the crown moulding and baseboard in this scene, I've used a Sweep modifier with a custom pattern.

For some reason, when I apply a UVW Map (plane or box) and a material to these objects, it causes a weird lighting/shadow effect, as marked up in the attached screenshot.

When I remove the UVW Map, the issue goes away (but then my material doesn't look right).

The same scene in 3.5 didn't produce this strange effect. Only came up when I upgraded to 3.6. Tried resetting V-Ray settings to default. Have tried converting to poly, but the same issue persists.

Any suggestions?

(3dsmax 2017 Update 1)

[tinybot]

(Note: Using 3ds Max 2017 with Update 1) -- (getting permission error trying to edit my original post)

[Alex_M]

Hmm.... looks like smoothing artifacts. They typically appear at the corners of sweeps. Did you check if your object is properly smoothed? You can try to disable Smooth Path in the Sweep modifier. If it doesn't help try manually smoothing it with Editable Poly and smoothing groups.

[tinybot]

Hmm.... looks like smoothing artifacts. They typically appear at the corners of sweeps. Did you check if your object is properly smoothed? You can try to disable Smooth Path in the Sweep modifier. If it doesn't help try manually smoothing it with Editable Poly and smoothing groups.

Thank you, sir! That did the trick. Turning off the Smooth options in the Sweep modifier resolved the issues for me.