Hi, Bob.
Just came across this on a newsgroup:
Question: >greetings, at the fab shop where i work we use prismacolor verithin ( >> silver )pencils to lay out dimensions on (mostly hot roll )mild steel. the >> problem we are having is that the lead tends to break off in the pencil >> and we have to re-sharpen to get a point. on average about a quarter of >> the pencil is wasted. these pencils are not intended for metal work but >> the silver color makes for lay out lines easy to see so i am curious as to >> what other fabricators might use. >> many thanks cj >>
Answer: Switch to Berol 949 Silver pencils. Made by the same company as your current Verithin's, but the lead is about 1/8" diameter. Welding supply and Art supply stores are the sources around here. For stainless they make a large lead dark red that works . Eyeliner pencils work well on stainless also.
I got started on the silver pencils while millwrighting in the local sawmill's around
25 years ago. A little expensive, but well worth it. I'm not sure if I even own a piece of soapstone any more. Where the pencils really shine is on wet/dirty/oily metal. They will mark where soapstone doesn't work. Also the mark doesn't blow away ahead of the torch.
Pete