A new year, a new blog. Last year I acquired a wheel-building habit. Much of my discretionary time and a large portion of my discretionary income were devoted to this craft. This blog is where I write down lessons learned from countless hours and dollars expended in my wheel-building pursuit. Now for some substance...
First carbon rim build
In 2012 I crossed that
great carbon rim rubicon. The ultimate objective was to learn enough with some
practice builds so that I would be able to build a solid 50mm carbon wheelset
for my cyclocrossing friends. I built with Zipp, two Chinese suppliers, and one
Taiwanese supplier (Gigantex). I approached the carbon rim with fear and
respect. I rode the initial builds so it was my own neck I was risking. As Alberto Gonzales would say: mistakes were made.
Lesson 1
Carbon rims
will make rude noises when you are tensioning the spokes. Carbon is not for the
squeamish.
Lesson 2
High profile
rims (+30mm) are very stiff and can mask vast differences in spoke tension even
within a wheel that is round and true.
Lesson 3
3x on 16mm
nipples is a terrible idea when used with high flange hubs and 50mm rims. Go with 2x and 12 or 14mm nipples.
Conclusion
Aluminum
hoops are beautiful and strong; they're fine for most applications. Carbon
clinchers are the dumbest idea ever: they don't save you that much weight;
they're vastly more expensive; they have crappy braking and require special
$60/set pads; they ride like shit because the rims are so stiff; and if they are not compressed by proper spoke tension, mounting a tight clincher (Conti GP4000s) can be next to impossible.
Think
carefully before buying a 38, 44, 50, 60, or 80mm carbon wheelset. They will be
fun and fast, but the impracticalities of riding with them (needing long stem
innertubes or *blech* long stem tubulars) and the discomfort (tall rims are
very good at transmitting shock to your wrists, arms, shoulders, and upper
body) may lead you to park them in favor of higher spoke count aluminum
clinchers.
New wide rim supplier
With HED C2 rims running
100-120 bucks and in scarce supply this year, I explored new options for wide
(23mm) clincher rims. The H Plus Son Archetype is a great alternative to the
HED: same width; same ERD (591 vs 592); nearly the same weight; and more
tolerant of high spoke tension due to its semi v-profile. As a bonus the
Archetype is half the HED's price.
First builds with Sapim
I'd stayed away from
Sapim until now. The reasons: DT Swiss spokes worked just fine, they were
affordable, the CX-Ray spokes were simply too damned expensive, and no one
seemed to be carrying Sapims.
That was until I had to
use Sapims due to a particular manufacture's hub design flaws. Sapim Race and
Laser spokes (J-bends) are fantastic; they're lighter, stronger, and less
expensive than DT Swiss. When paired with Sapim Polyax nipples (my nipple of
choice) they build a very tight wheel.
Construction of a wheel-building database
Prior to building my own
database, whenever I built a wheel I would have to research the rim and hub
dimensions, and then use the DT Swiss spoke calculator to determine spoke
length. That worked ok for one or two wheels, but the process became cumbersome
for anything more than that. With a relational table database, I have access to
the dimensions of all the rims and hubs I've ever used, as well as a record of
the spoke lengths and lacing patterns of the wheels I have built. As an added
bonus: the database will calculate spoke lengths for me.
Use of Linseed Oil for
spoke prep
If you have done any
background reading on wheel-building, you are likely to have come across the topic of
spoke prep. For the uninitiated, spoke prep is thread lock that is applied to
the spoke threads to keep the spoke/nipple from loosening over time. The spokes
in a wheel are subject to a tremendous amount of force both radially and
laterally. Those forces can, over time, lead to the wheel softening due to
spokes coming undone. That is less likely to happen with thread lock.
The problem with using
conventional Wheelsmith spoke prep: 1) it is expensive (30 bucks for a few
ounces); 2) it adds time and mess to the wheel-building process; and 3) it can
really hinder the building if you happen to get too much spoke prep on the
spoke threads. DT Swiss sells nipples already containing spoke prep (Pro Lock)
to save you some time. Problems: 1) they're expensive; and 2) you still have
the problem of spoke wind-up.
So, knowing that the old
school builders once used linseed oil, I went down to the local hardware store
and bought a quart for 10 bucks. It is fantastic; I am never going back to
spoke prep. Linseed acts as both a lubricant (between the nipple and rim) as
well as a thread lock. Afterward the build the mess is minimal and easy to
clean. Note: even when using conventional thread lock you still have to
lubricate the nipple/rim interface. Using linseed oil combines all
wheel-building prep into one step.
Building with
straight-pull hubs
Sucks. Never trust the
manufacturer's dimensions. Normal spoke calculators do not apply. Spokes are
more expensive. Wheels are no stronger or lighter than conventional j-bend
spokes. Yes, you could retort that the straight pull eliminates the major weakness
of the traditional spoke (elbow fatigue). In reality this means nothing because
I have never seen a failure at the flange of any properly built j-bend spoke.
My best wheels of 2012:
- Roger's front wheel. Specs: Velocity A23 24 hole, White Industries H2, DT Swiss Revolution spokes, 14mm Sapim Polyax nipples, radial lacing, and spoke tension of 110 Kgf. I plucked those spokes and they were uniformly in pitch. Then I plucked the spokes of the new Ksyrium Equipes on my significant other's new Cannondale. I was embarrassed for Mavic.
- Mateo's cyclocross wheelset. Specs: Yishun 50mm carbon tubular 20/24 spokes, White Industries H2/H1, Sapim Race, 14mm Sapim Polyax nipples, and 2x lacing all around. Withstood the rigors of cross racing while remaining round and true.
