What different type of refill leads are appropriate for outlines, dimension lines and construction lines.?

Question

For automatic pencil

Answer 1

Nowadays we use different thicknesses of lead

in different pencils to get line types.

I still, when the project isn't on CAD, use harder leads

for dimension & construction lines.

.3mm Constr. & Dim.s .5 & .7mm for outlines,

.9mm for lettering

'Back in the day', when we used one dia. and

sharpening, we used harder leads for fine lines

and softer for heavier lines & lettering.

4 or 5 H for construction, 3H for Dim.s, 2H for outline,

H for heavy lines ,(diagrams etc.),  and HB for lettering.

Thanks for the 'blast from the past'.