RE:oxalic acid/ graphite

[Bill Wichers <billw at waveform_net>]

> >Graphite could probably be acquired from a >theatrical lighting supply 
> house
> >in the form of electrodes for carbon-arc lights
>  >(very old technology
> >though, might be hard to find). Titanium is also >pretty inert, and should
> >be more durable as well as easier to find
>[snip]
>isn't your average pencil core simply graphite?
>elie

Yeah, with some clay added to make it harder (higher number on the pencil = 
more clay and a harder "lead"). The pencil graphite is really brittle 
though, and also very small. I suppose it could be used if you were patient 
enough to work with it. I remember trying to make something once with 
pencil graphite and had a lot of trouble connecting a wire too it due to 
how easy it was to break. The pencil core usually is pretty small too, and 
the refills for drafting pencils (much larger than normal automatic 
pencils) is still about 1/16" diameter or so for the largest sizes I have 
seen. Just seems like it would be a lot of work to try to use pencil parts 
over other things. The carbon-arc electrodes are usually 1/4"+ diameter for 
the old-style fixtures, and the titanium rod I suggested can be had up to 
several inch diameters if you have the $. Titanium can also be worked more 
"normally" as a metal instead of graphite that tends to crumble easily.

         -Bill
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Waveform Technology
UNIX Systems Administrator