Thanks!
Second track out - looks OK.
Turret printed overnight, looks OK at first check but might reprint as the layer lines appear quite promenant on the mantle. I'll reprint in a different orientation.
Problem is the best orientation is flat but this causes a 'softer' edge to the turret.
The problems arise when the curved surface approaches the plane of the print.
This is because, like a contour map, you get fewer contours so you get a much more noticable steps.