ChocoPI: Mathematical Symbols in Chocolate

It
all started off with an idea in December 2005: to produce
chocolateletters with mathematical symbols. The letters would be sold,
at a price to cover the costs, to the public attending the yearly
Reunion of the National Organisation of Mathematics Teachers in the
Netherlands (NVvW). The idea stayed in my subconscience for quite a
while, but in July 2008, at the end of a a Sabbatical Year, it sprang
out again.

Doing
an internetsearch I found out that a a mould could be produced at
FabLab Amsterdam. A couple of days later the work started. We (Mike
Pelletier, a FabLab volunteer, and me, Hans Wisbrun, Wisc) started off
with the mould for the mathematical symbol PI.

The whole production process and it's follow-up are described in detail on my weblog (in Dutch): http://chocopi.blogspot.com/ 

Although still in the middle of the process some facts and findings:

• We sort of copied the process of producing moulds for Candies in the FabLab: http://fablab.waag.org/node/990.
• Although
  we used a light material to mill the positive mould on the Modela-20
  (styrofoam) the milling lasted for many many hours (disappointing); I
  would have expected one or two hours, at the most.
• Styrofoam
  is a very vulnerable material; if you accidentaly scratch the surface
  with your nail, the surface won't be flat anymore, so won't be the
  letter; chemical wood probably would have been a better choice, for
  sustainablity reasons; we tried MDF, but that material was too hard.
• Styrofoam breaks easily.
• To produce ten negative moulds the choice for styrofoam was OK though
• But to
  produce more, we would have to mill a complete new positive one; the
  first one can't be used any more, it's now too scratched/demolished.
• We used siliconerubber (Smooth Sill 940; food grade) for the negative mould.
• Smooth
  Sill 940 is extremely expensive material, but relatively ease to use
  (you mix two components & do a lot of stirring). We had to use
  about ten kg for ten moulds, which costed a fortune (EUR 400).
• Chocolatiers
  (students from a Bakery-school will fill the moulds with chocolate;
  producing chocolate is really a specialised job) prefer hard material
  for moulds, because of their own methods.
• If
  we are going to repeat the process (this was just an experiment), the
  whole process should be re-designed. Special attention for the
  materials to be used; I got doubts over the Modela-20 too, because of
  its extreme slowness.

Some advise:

• Plan ahead; think about the whole process until its final stage (people eating the chocolate)
• Start
  to create publicity for your idea/product at an early stage if you
  think that there is a market for your product (my original idea was to
  produce just 100 letters, but I sold about 200 easily). I started a
  weblog http://chocopi.blogspot.com (in Dutch) and wrote an article for a magazine for Dutch Teachers of Mathematics (Euclides). See attachment.
• Do
  experiments with a webshop at an early stage. This experiment made it
  clear that a webshop might be a perfect place for distributing things,
  but NOT a chocolate letter. It will break during shipping.
• You
  can earn money by projects like this one, but don't expect that. I just
  succeeded in covering the costs. But I gained a lot of enthusiasm and
  positive reactions!