Day Three

The capillary-action pen is easy enough to make on a smaller scale, and it works really well with inks made from food colourings. Let’s hope that Ellen manages to produce a natural ink that’s just as usable. I’ve every confidence in her, as she’s been beavering away at her ink challenge for two days now.

As for the smaller ball-point pen – well, that’s a bit more difficult. Just by chance, I notice there are some bicycle wheels in the workshop – presumably for use in Jonathan’s ‘Mars Rover’ challenge in Programme one. Inside the hub of one of the wheels is a ball-race with some small (about three millimetre diameter) ball bearings that are just the right size for my smaller ball-point. What’s more, one of the caps from a superglue container serves perfectly as a housing for one of these small ball bearings if I cut just the right amount off its pointed end.

By the end of the day I’ve four different pens, each of which works (in a way). What’s more, Ellen’s managed to manufacture some natural ink that fits the bill perfectly. What seemed an easy challenge has turned out to be more demanding than I’d first imagined, but we got there in the end.