I’m looking to build my first lugged fork and I am curious how people draw the forks. Specifically, I want to know how people tackle the vertical distance from the crown to the top of the fork blade. I’m assuming all crowns are different and there doesn’t seem to be a good way to measure this distance.
I’d love to hear about y’alls processes!
Place the crown upside down on your surface plate. Stick in a fork blade. Measure the total height. Measure the length of your fork blade. Subtract the two.
I was taught to use the backside of a caliper to measure the fork crown socket depth. Make sure the caliper rod rests against the shoulder inside the crown casting, not the bottom of the socket.
I use a caliper like Jim does above. Some crowns do not have a defined blade seat, but this works great for those that do. First I measure the inside of the blade socket from the longest point to the blade seat. I then measure from that same point vertically to the crown race seat. Hold the leg sockets against a flat surface, then measure vertically from in between the blades to the crown race. Subtract the two, and you have the blade seat to add to your drawing. I also measure from the crown race seat to the bottom of the crown so I can dial in tire clearance.