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@BenH
The first bits of CF went on in the last couple of days - I've been working away so haven't had time to do much. Will post pictures when I have time to take good enough ones - it's hard to get them when you're covered in epoxy.
Reflections so far - unidirectional tape is much easier to handle than tow, and the thin strands of fibreglass used to hold the tape together provide a very useful visual guide of whether the carbon is properly wetted out (they go virtually clear). Peel ply tape is also very useful, though it is a bit difficult to get it tight on complex joins - it's 50mm thick and doesn't stretch. Perforated electrical tape over the top of peel ply would probably give you the best of both worlds, as the PP is very good at making sure you use just the right amount of epoxy and get super bonds between layers, and the electrical tape would compress it even better. I'm slightly concerned that using just vinyl tape would not encourage strong lamination as you end up with a thin layer of smooth epoxy on top of each layer of carbon. PP sucks out excess epoxy (though in practice you generally have to add more to wet out the PP fully anyway) and leaves a great texturised finish.
For reference, you want appropriately 11-12 grams of epoxy to 10 grams of carbon to wet it out fully. Considering the density of epoxy is about 1.1-1.4 g/cm^2, a reasonable rule of thumb is a millilitre of epoxy to a gram of carbon; 25mm 200gsm UD tape is 5g per metre. Add a little bit for pot/brush wastage.