He decided upon.046 inch lead, which became the industry standard for “thin” mechanical pencil lead (today the most popular sizes are 0.5 mm and 0.7 mm).

Prepare the Pencil Lead: Start by carefully removing the lead from a mechanical pencil. The lead will act as the electrode in your plasma cutter. 2. Set Up the Batteries: ...

It may not be mightier than the sword, but a new mechanical pencil is sturdier than the usual kind that easily breaks. ... The lead won't break under normal use, according to Zebra.