scribing dividers ?

Hello again all

Is there such a thing as a "scribing divider" ?

Useful for when working on "black" steel? Will cut-through / mark the mill-scale surface?

Maybe about 10inch/250m to 12inch/300mm "legs".

If I recall rightly I have seen dividers where each leg has a smallish about 3mm very hard steel/carbide cylinder ground to a point. Which can be demounted/unclamped and resharpened.

If so, what are these known as? Not doing well looking in tool catalogues.

Else - is the answer something else like dividers with a point at one end yes, but a chalk / soapstone at the swept end?

Regards, Rich S

---------------------- Trammel points?

I have a divider that has a sleeve with setscrew to hold a pencil or round soapstone . It's about 9-10 inches long .

Trammel points yes. Forgotten about those. Yes they would be "the thing".

Useful for when working on "black" steel? Will cut-through / mark the mill-scale surface?

------------------------------- I freehand grind my scriber tips from broken HSS taps and 1/8" shank carbide drill bits. A pin vise collet can hold them.