Just a standard HB pencil in this case Michael.
The wing roots, leading edges and fuselage also have the pencil marks, but they can't be seen clearly in the pics - the lines need to catch the light to be seen clearly, hence the need for good light when spraying.
Those areas which could suffer from 'overspray', such as leading and trailing edges of the wing, the undersides of the tail planes, and the underside of the fuselage, had already been masked before spraying the Dark Earth.
The tricky part, at least for me, with my knackered hands, is getting in to areas such as the curve of the wing roots to fuselage, keeping an accurate line whilst spraying. It just takes a little more time, doing small areas in stages. Once the edge demarcations are sprayed, it's a fairly simple task to 'fill in' the rest.