Here ya go. You mount the caliper on a bracket that goes directly to the axle and can rotate on the axle on a bearing (bushing). Near where the caliper mounts to the bracket, there is another small bushing. This is called a lower stay rod bushing. The upper stay rod bushing bolts to the fork crown.

When the bike is moving and you apply the brake, the caliper pulls down on the stay rod causing the brake force to move upward directly toward the upper stay rod bolt where it belongs, in a nice thick chunk of metal.

Welding a gusset on a skinny tapered blade is so very bad. There is nothing about a tapered fork blade that should be near a disk brake caliper unless it is very large, thick and straight. Torch brazing on the fork blade will jeopardize the condition of the material in a critical area. ending the gusset at the drilled hole is so wrong it's not even funny.





road-brake by frankthewelder, on Flickr