Many thanks. However, you lost me at Planar the offsets part. I have a managed to do it though.

However, I now have a more challenging version. I need the same thing doing again, but this time it's on a curved surface!

Please explain this as though you are talking it through with your mother... I do have a degree, it just it's not in anything computer or CAD-like! Sometimes people think you have some basic knowledge so assume they understand and skip bits they think are obvious.

Thanks again

Gordon