modified 11 years ago

Pencil Lead Resistors

00:19:01

Top line is long pencil lead.
Unbroken pencil lead can be used as low value resistors (1 - 5000 ohms).  Wooden pencils or mechanical pencil lead can be used. Wooden pencil cut off eraser and metal top.  Measure resistance of total length of pencil lead and cut slightly longer than needed ohms.  Bend wire around nail about same diameter as lead , crimp slightly and solder on wire being careful not to damage or break lead.
Also,  for adjustable resistor, make slider connector to use with long piece of lead
Wood pencil tapped at several points with wire pigtails can may be used.
Resistance of lead depends on type, diameter, and length.

published 11 years ago

faceblast

11 years ago

be careful with power because they catch fire easily! great fun though

pmlmobi

11 years ago

Yea you could even make yourself a lightbulb from those. Or use them as one-use igniter.

stanislav_maslovski

11 years ago

also played with that when was (much) younger :)

faceblast

11 years ago

if you get two sharp pencils and put power through them with the sharp points just touching slightly it makes a really bright carbon arc lamp. wear welding goggles though because you'll go blind

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