Fork alignment

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I am almost finished with my girl’s fork for her new steel 26″-wheel frame.  For this fork I used True Temper FB-4 fork blades since the axle to crown length is only 432mm.  There’s enough room for a 29er too if she ends up wanting a big wheel up front.  I love the look of this fork with the tapered blades. I silver-brazed some Nova plug dropouts for ease and they just look clean with these blades.  The upper crown segments are cut from longer segments of 1″ x 0.049″ 4130 from Aircraft Spruce.

For fork alignment, this is what I do…and I have no idea what others do but this makes sense to me (in order with the slideshow, except for the cold-setting which would be very difficult to take a picture of!):

1) Clamp to the steerer into the big v-block on the granite block.

2) Then I vertically align the fork with a long machinist square at the crown, and check to see if the legs are in line at the dropouts (is there any twist?).

3) Use Mr. Wetmore’s fork/frame alignment gauge and center it on the steerer tube.

4) Check leg alignment with the gauge to see if there’s any shift to the driveside/non-driveside in the legs as well as spacing for a 100mm axle.

5) If the legs are out of alignment, either weld a 2nd pass in the right place, or stick the steerer  in the big vise and try to cold-set the legs back into alignment. For this fork I tried cold-setting (bending). It worked fine but not without some serious elbow grease.  All the welds look equal and good on the 1st pass though so I didn’t want to overheat them…but not sure what’s better at this point – second pass or cold-setting…?

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