Offsetting a curved edge

please see screen shot attached, how can I create an offset edge on a curve

I am modeling some cabinets and in particular cabinet doors, which will be curved. Normally i would create an external dim, the use offset to create a shaker style door, but unable to do this on a curved face,

Any ideas?

In this case I would start a sketch on the top face of the cabinet, offset the curve and finish the lines to extrude a new body downward.

Thank you and sorry in advance for questions;

I am unable to draw onto the curve, to extude etc?

This maybe a very simple thing, but i have been trying different ways for hours

You can project lines onto a curved face, you cannot sketch onto a curved face.

But then you cannot push/pull to create door detail?

You can you just have to plan it using project tool.

Just wanted to mention another option. You can use a line and cut from the top and the side.

Limitation of working on curved surfaces. :man_shrugging:

Offset edge doesn’t work on curved surfaces as far as I know,

What you can do it project the curve face to a plane, then use the offset edge tool and project back to the curved face.

Sweep tool also depending on what you want to do.