Bob,
That's an interesting method I've never heard of before! I suppose it may not work the same if one was using standard type dropouts. I've never used the plug on type.
I'm with you on what Tesch used to call "knee bent" fork blades. A sharp kink in the middle of the blade with a long straight section is the absolute worst. Often the sign of an amature framebuilder. The true artist is very aware of the beauty and gracefulness of the fork; not only the bend, but how the dropout blends with the curve of the fork blade and how the design of the crown mates with the design of the lugs, etc.. I prefer the long gentle bend beginning high on the fork blade and blending perfectly and smoothly into the dropout.
The method of bending the blade first, then cutting off the end that is always a little bit straight at the point where it results in the correct amount of rake, and then slotting for the dropouts is the way I do it. That way I can make two fork blades exactly the same, without any funny bends or kinks. Kind of old school but very exact; I have complete control over the bend, dropout placement, amount of rake, and brake drop on every fork. Since my forks are individually designed for every bike, I can incorperate any and all varaitions of crowns, dropouts, and dimensions quite easily this way. It's good if everything is custom; perhaps unneccessary if one is making production frames to whatever degree.
Brian Baylis
La Mesa, CA
> You build a curved blade fork one of two ways: either start with
> curved blades (and hope they're the same), jig it up, braze, OR start with
> straight blades, braze, bend (and hope they bend the same). Adjust as
> necessary for
> alignment.
>
Ah but there are yet more tricks. In the shop of that noted Italian-American framebuilder of 30 years experience, Guillelmo Davidsoni, we first braze the crown to the blades and steerer in a miraculous inside-out manner than allows us to pull the brass from the inside out until it just makes a nice edge at the lug edge,without splattering all over requiring much cleanup. Then we bend the blades on a dual bending mandrel so they are exactly the same (assuming they were exactly the same to start with of course). Then we cut off the bottom ends in a special patent Davidsoni jig that allows them to be cut off square and at the same length, for the insertion of plug-type investment cast dropouts, and voila! Perfectly bent forks that have a nice gentle curve all the way to the end, with no kinks from the holder at the end, because you cut that part off. My pet peeve has always been those buttugly forks that do all their bending in the middle and have a 3 inch straight section at the bottom, or else are curved after brazing in the dropouts and so have the telltale little kink. And I also don't care for those lazy-ass straight forks. They just don't look right, even if Ernesto will not build them any other way ever again because it is the perfect design. Give me the gay ones any day.
A little trade secret/Christmas present for you all who are so socially deprived that this is how you spend Christmas!
cheers and ho-ho-ho
Bob Freeman
Seattle