To have the frame aligned perfectly, the centre line of all components mounted on the frame jig must be the same, i.e. the same distance from the base of the jig. Allowing for the frame being assembled horizontally above the base board of the jig. This means that the metal parts, head tube, bottom bracket, midpoint between the dropouts, all need to be the same height above base board of the frame jig, also the mid point of the seat post. This should occur naturally, but even a millimetre or two, here or there, will put things out of alignment. And, allowing for the fact that not all parts of the frame jig went together easily (and there is no criticism of the kit here) there was plenty of room for error. Throw in the fact that the head tube itself needed to be horizontal (same height at both ends) and you have another potential for error. Finally, the dropouts needed to both be the same distance from the bottom bracket (and I had taken a deliberate action to shorten this distance) and without this equidistance the back wheel would fall out of alignment (and not present a perfect line in same direction as the frame). So, when the frame was removed from the jig, one of the first things I did was check the back wheel alignment between the seat and chain stays when the wheel was fitted fully forward (up against the stops) in the dropouts. Things here looked great and at least as good as most of my production bikes. Then I checked the frame/dropout alignment using a method published by Sheldon Brown (it checks that the dropouts are spaced equally on left and right of the centre line of the bike. A simple crude but effective check with some string tied to one dropout, brought forward around the head tube and then back to, and tied to the opposite dropout. If the frame is true, and the dropouts are equidistant, then the string should pass by either side of the seat tube and the distance between seat tube and string should be identical on both left and right sides. They were. The only thing that I couldn't check was the head tube being aligned exactly with the bike centre line i.e. being perpendicular (on left/right plane) when the bike is upright. This is not likely to be incorrect and will have to wait until I get fork, heasdet and wheels properly installed so I can check the wheel line on the road.
A white fork, and one with some black/blue decoration, just did not match the bamboo frame. I decided to do something about that whilst awaiting the hessian caulking to dry. So, I bought a can of car spray paint (Rover - Russet Brown - I liked the Rover cars of the 70s) and already had some clearcoat spray in a can. So I set to work, some very light roughing of the existing paint/clearcoat, not wanting to cut through to the carbon fibre, and then masking, three coats of brown followed by two coats of clearcoat. Not too bad - a little run off and bubbling on one side but so little that I decided mot to attempt a fix. Resulting colour is a much better match.