drilling pencil lead on a lathe

Electrical discharge machining.

Also know as spark erosion. A well known technique for removing broken taps from metal.

Depending on the capability required, they can be easy home-shop projects.

yes

so that is how they do that

are there off the shelf units i had never heard of it but now will have to look some time

in this competetion the operator could not see as it progressed but instead listend and watched the bubbles

seems to work in a variety of material too steel aluminum and pencil lead

wonder if it could be used in wood

Commercially yes but not at prices you or I would want to pay.

I think it requires that the material be electrically conductive. I'm surprised it works with graphite (not because of it's conductivity but the nature of the material).

I saw a simple one demonstrated at a model engineering show and the plans to build it were on a single sheet of A4 paper, I bought a set, and it wasn't tightly drawn. A second much more elaborate one was featured in "Model engineers workshop" (UK magazine) over two monthly parts.

I've seen nice, intricate, patterns cut into razor blades. Hardened stainless steel and difficult to cut any other way because it's so hard and thin.

also what i thought

there is a part two of the video that i have not seen the operator mentioned that 12mm deep is the critical point and that is where part two starts i think

will have to look for that

what i have seen so far was all small scale

but i wonder if it is also used at large scale

It must be true...A keyboard with no punctuation keys...Why else would someone go thru the effort of typing 5 letters in lieu of 1 simple keystroke?

was wrong on the diameter

the winner drilled a 0.3 hole through a 0.5 lead on a lathe

did not see what happened to the edm competitor but in part 1 he was concerned about the depth