While I make up the prototypes, especially at this early, rough and ready stage, I tend to scribble notes on the model and write on dimensions I've measured with my calipers. You can just see some on the picture above. The models are prototype and experiment lead, things evolve and change in a fairly fluid way. I will pull apart and re-glue a model to try out minor variations. Then reuse working parts having cut away none working bits.
In the case of the Ewe boat the prototype looked fairly similar to the finished item, but sometimes they are unrecognisable! If I can find it I'll put up a picture of the original Surfin' the Web! Blimey!

Anyway, next step is to transfer all the bits onto computer and make a black and white mock up. Once on the computer it is easy to make small changes and reprint the model rather than having to draw it all out again with pencil and ruler.

This one looked good but there was something lacking in the movement. I wanted a model that really p-u-l-l-e-d at the oars! So, a slight change to the geometry, I increased the offset of the cam and moved the boat slightly further away from the box. It's usually not a good idea to change two variables at once but it worked okay this time. Phew!

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