Elliptical weld heads visible line, ??question

[MAGNUT45]

Using INV 10 but noticed this in 9 too.
When I draw an elliptical weld head, the ellipse line on the sketch is visible. Any ideas on how to get rid of it?
It stops me from making a weld around a penetration part.
This happens if I use shell or sketch the complete profile.


thanks for any help