Before any building can occur, you must have a well developed design. The great part about a wood bicycle is that you can cater the bike frame exactly to your fit and your needs. I used solidworks as a design platform to draw and model my frame. I essentially started with the geometry of my road bike, because I knew that it fit me, and then adjusted it to have the triathlon qualities I was looking for. Notable adjustments I made were increasing the seat tube angle, adding an airfoil shape to the down-tube and seat-post, lowering my seat-stay attachment, and adding a profile for the back wheel.

It is important during this step to keep in mind the components that you will be using for the build. The wheels, seat post, steerer, and bottom bracket insert are all sizes that are especially important to get right.

The computer model should have the ares of the tubes that will be hollowed out to save weight. I left about 6mm walls in all of the tubes.

Finally, you should get the outline for the main triangle printed on a 1:1 scale. I was able to get an engineering-printing company to print me two copies for about $5.

The bike will be made by laminating thin plies of the wood together. By doing this, you can take advantage of grain direction in key parts of the bike to improve strength in multiple directions. My bike is made up of 8 layers of plies. Because it is symmetrical, I made 4 plans of ply orientations that would be mirrored across the center of the bike. Above is a picture of how I planned these layers on solidworks for another bike I made. For the head tube (which encounters a lot of stress) I made sure to include + and - 45 degree angles from the steerer axis for 4 of the layers and longitudinal with respect to the top tube and down tube for the other 4 layers. For the joints of the down-tube/seat-tube and top-tube/seat-tube, I made sure that the plies coming in overlapped every other ply so that the joints would be well integrated.