Wheel Building Tip No. 9 – Succeed with Alu Nipples
[Note: this is #9 of a series of 20]
Back in the 1970’s, aluminum nipples were rare. We had superlight tires (<200g), superlight rims (<260g), and superlight spokes (butted 15 ga), but no one thought about aluminum instead of traditional brass for nipples because the weight savings is small (~20g/wheel) and a nipple failure is just as bad as spoke breakage. The only aluminum nipples available were made from inferior alloys and didn’t impress serious riders and builders.
In the 1980’s, companies like DT and Wheelsmith set their sights on making high quality aluminum nipples. In Wheelsmith’s case, the solution was four-fold. One, use 7075 aluminum, which has superior hardness. Two, make the nipple with 30% more threading so the chance of stripped threads is reduced. Three, forge the nipple rather than machine it to shape, to increase metal integrity. Lastly, rely upon recently developed thread compounds (Spoke Prep) to reduce friction and prevent corrosion, both a much greater concern with aluminum than brass. Read more →