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,


Thursday, September 16, 2010

Juli's Wheels -- Pieces Parts

The wheel building class at Broadway Bicycle School started this week! I drove into Cambridge in one of my folks' cars, because Allyson was in town earlier this week, and she'd borrowed my Mazda for a few days. Borrowing seldom-used "spare" cars isn't always a good idea, and this week it turned into sort of a carnival of gremlins. I managed to avoid crashing into anything or being bitten. Long story.

Class was good. I'm one of three students, so it's a smaller and so far more social group than my last group. Each of us is building a different type of wheelset, with different hubs and different rim sizes, so it should be interesting to see how each project progress.

As I've mentioned before, my project will be to lace a set of 650B rims (either V-O or Velocity, depending on what's available) onto a vintage Specialized sealed bearing hubset. I think I properly spaced the rear hub for 126mm spacing (it was 120, originally), but we may need to adjust that in class. The 126 spacing will allow the rear to host a 7-speed freewheel, and then the final assemblies will see duty on Juli's new-to-her Schwinn frame (which is only a handful of parts away from being buildable).

This week, we mostly talked about what we wanted in the way of wheels, and why, and then chose parts. I already had my hubs, and knew what my rim choices would likely be, so most of the class I listened to and supported the dialog around the other students' wheels, which were being built from new and as-yet-unacquired parts. Did you know a Rohloff hub can run $1700, retail? That's a big nut, but then again, there's a little 14-speed transmission inside the thing, so it's a pretty sophisticated piece of equipment.

Apart from already knowing my rim and hub selections, I did have to make a couple of choices. I hadn't given any thought at all to spoke or nipple type. I think (can't remember for sure) I went with straight gauge DT Swiss spokes (vs. butted spokes), and I know I went with chrome plated brass nipples. The straight-gauge spokes are heavier, cheaper and not as strong as butted spokes, but these are wheels for a kid's bike, not a bike I'm going to put a thousand miles on per year.

To me, the way wheels lace up is really pretty cool. In a sense, spokes are long and skinny bolts, and nipples are nuts. The spoke winds through a hole in the hub, and then runs outward to the rim to accept the nipple. The nipple, in turn, fits through a hole in the rim and then threads onto the spoke end to hold it in place. Arrange a bunch of these around the circumference of a hub, running in a pattern to the rim, tighten them to uniform tension (either across all spokes or per-side, depending on the situation) and you have a wheel.

But there's a lot of detail in getting the wheel built right -- spoke length, choosing a lacing pattern, getting the path for each spoke right for the pattern, centering the rim properly (relative to the outer locknut surfaces on the axle), and getting everything tensioned properly and consistently. You should see the formula used to calculate the spoke length!

It should be a fun experience, and I'm looking forward to going back in two weeks to see what the Velo-Orange rims look like, and start learning how to lace the wheels up.

Then, once the wheels are built, I'll still need a few things to get the build rolling:

650B tires, and something on the narrower end to work with the chrome fork I bought for the frame
650B tubes to match the tires
Rim strips, and I'm going to try the new Made-in-America ones from Rivendell
The aforementioned freewheel
Brake and shifter cables, and housing in Juli's chosen shade of blue
A threadless handlebar stem, starnut and cap
Blue "cork" handlebar wrap
A kickstand

And probably a handful of other small parts, as well. Not a lot, though. The build should make for a good Christmas break project, I think, with a Thanksgiving tear-down of the Fuji.

I'll keep you posted.

All for now,



Have you ever known anyone really wise? Someone who says important stuff that seems to make some sense at first, but then maybe a year later you really understand what they meant and why it was important? I do. A handful, actually, but one in particular inspired this post, after several weeks' hiatus.

I'm not sure if this dynamic makes me slow on the up-take, or if it makes those people especially wise. I'd like to think it's the latter. But I will also admit to blind spots.

My advice to myself is to listen harder to wise people, and spend more time thinking about what they've said. I think I'm getting better at that, but listening is a lifelong skill that can always use more work.

All for now,