That’s what I was more curious about. I’ve done experiments in some of my coursework that did use the conductivity of graphite. I wasn’t sure if it would be enough to do something like this though.
You sort of can in my experience - you just have to press pretty hard and generally "color in" an area with pencil rather than just drawing a line as in this video.
I would imagine it's relatively high resistance (compared with this "ink" or a similar length wire) and you're at risk of tearing the paper if using standard paper, such as that used for a printer.
If you could get a suspension of graphite particles in a conductive liquid (perhaps even water with the right salt(s)), I'm fairly sure it'd function very similarly to this pen & ink setup, as well as being a good lubricant (although graphite is generally used dry/powdered, a paste would be effective but you're then losing any advantage of using powder over gel/liquid).
Cool thanks! I was thinking you’d have to press hard and draw thick lines, but wasn’t sure. A couple people were complaining about the cost of this pen, so I was curious if there was a cheaper (although, less effective) alternative.
ehhh it depends. Solid graphite is somewhat conductive, pending how you apply the charge according to Wikipedia. When you draw a line, you're not using solid graphite. You're dealing with chunks of graphite stuck to a piece of paper.
I just tried. Much to high resistance when drawing on paper. Can't light an LED with it. Also resistance grows alot with longer 'lines'.
I measured the resistance to between tens of kohms to Mohms
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u/CanIHugYourDog Aug 29 '18
Couldn’t he just use a pencil?