Tuesday, September 28, 2010

Juli's Wheels -- Lace 'em up!

Last night was what I suppose I'd consider the "big day" in my wheelbuilding class at Broadway Bicycle school -- I laced both of the hubs into the rims!

Now, on the scale of human achievement, this isn't really all that big a deal. Millions of spoked wheels are produced worldwide each year, after all. But these two are my first, and may well be my last, so I'm going to savor the experience.

So what'd I do? Well, I started with several sets of components -- two Velo-Orange Diagonale 650B rims (so shiny and pretty), a pair of sturdy old Specialized sealed bearing hubs (not shiny or pretty, but stout and bulletproof), fifty-two 276mm stainless spokes for the front and non-drive-side rear, eighteen 274mm spokes for the drive side rear, a GladWare tub full of chromed brass nipples and two different colors of Spoke Prep, which is a type of thread locking compound. Then Dave led the class through the process of lacing up the wheels.

The first step was to smear Spoke Prep on the threaded ends of the spokes. The two different colors were to distinguish the spoke lengths -- the long ones got the taupe-colored spoke prep, and the short ones got the baby blue. Using two different colors would ensure that we wouldn't use the wrong spokes in the wrong places. Except when we (I, really) did.

Spokes prepped, the lacing began. Dave gave us some tips on how to show some deliberation about the details of the wheel. Stuff like making the logo on the hub body line up radially with the valve stem hole on the rim. And making sure the valve stem hole fell in the right place within the spoke pattern, to make sure it would be easy to get a pump head onto the valve stem. Or making the labels on both rims readable from the drive side of the bike. Stuff like that, both functional and aesthetic.

Those things in mind, we started lacing. Which really means threading spokes through the holes in the hub, and running them outward to the holes in the rim, then securing them with a nipple. It wasn't as hard as I expected it to be. Really, it was pretty simple -- just a matter of knowing where to start, which spokes to thread next, and which holes to run them to, given the desired spoke pattern (three-cross, in this case, which means that each spoke crosses three other spokes on the way to the rim).

I did make some mistakes, though. I was feeling pretty chatty, and at one point I realized I was using short spokes on the non-drive side, and I had to take like 6 spokes out of the wheel, and replace them with the longer ones. Then another time, I realized I was working sort of backwards, and had to take another 8 spokes out, twist the hub a bit, and then re-lace those 8 spokes again in a different direction. It could have been worse -- I caught both mistakes myself, and Dave was right at hand to offer course correction.

In the two hours of class, I managed to get both of my wheels laced, so I'll be in good shape to start the next steps. They are still pretty floppy, and there's still quite a bit of work left to go. I have to make sure they're dished right, which will result in the rim being centered between the outer lock nuts on the hub -- necessary if you want your rims to sit smack-dab between your brake shoes, which most of us do. Then they have to be round, with the axle sitting dead-center of the rim's circle, which I think most of us would intuit the importance of. And they have to be true, so they don't wobble like a potato chip while they turn. And perhaps least obviously, they should have even spoke tension across each side of each wheel, so that the wheel isn't overly stressed at any given point, which would lead to their prematurely getting out of whack.

So the dramatic part is done -- the part that makes it look like I actually did something. But the hard work -- the meticulous and frustrating work of making the wheels right and usable -- is still to come.  One of the wheels is pictured above, sitting at a bench at Broadway Bicycle School -- can't tell which it is.  You can see it pretty much looks like a wheel.  But the spokes are slack, and the wheels unusable as a result -- you can tell because the spokes are curved, not straight (they're not under much tension).

I hope Juli will be impressed by the final results, and treasure these, her father's first (and possibly only) wheels. If she doesn't, that's OK -- I will. And I won't remind her of all my hard work before every ride, I promise. I'm having too much fun to play that card.

All for now,


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