Monday, September 1, 2008

Wheelbuilding 101, Part 1

I had a nice long holiday weekend with no other plans, so I decided to start my wheelbuild. My first order of business was to get all my supplies and tools together in an area where I would be comfortable with adequate room. I have a so-called rec room in my basement, where my bikes, treadmill, entertainment center and couch live. It was kind of a teenage hangout before my daughter went to college, then it just collected junk.

Since my daughter has graduated from high school, we no longer need to live in this school district and decided several months ago to sell our house...crappy real estate market or not. Our first priority was to de-junk and paint. Luckily, we have a small mini storage facility nearby which made renting a bay and moving all of our unnecessary stuff relatively pain-free.

The rec room was the first area needing a clean up. A mini-fridge, many boxes, a bookcase full of books, and other miscellaneous items went into storage. This of course cleared more space for bicycles, bicycles parts and other cycling paraphenalia. I have turned this space into my temporary wheelbuilding shop.

I procured a portable workbench at the local Home Depot, which works perfectly as a table for my truing stand. It has a clamping table, allowing me to clamp my truing stand snugly in place and is at just the right height. I took my laptop downstairs and pulled up http://www.sheldonbrown.com/wheelbuild.html, which I used as a reference while lacing the wheels. All the information I needed was right at my fingertips.

I am building 36 spoke cross 3 wheels, meaning the spokes cross each other 3 times. My understanding is cross 3 wheels are the most common type, which I verified by looking at my old Schwinns, and my Quickbeam. Each bike has 32 spoke cross 3 wheels except for my LeTour, which has 36 spoke wheels. My wife's Giant hybrid also has 36 spoke cross 3 wheels. Per Sheldon's wheelbuilding website, 36 spoke wheels were the norm until someone got the bright idea to use lower spoke counts under the guise of 'performance'.

I did some research and there are many other alternative, more decorative types of lacings.

Although they look interesting, I don't think I have the chops (yet) for some of the more complex builds. Also, I found an interesting short video of a semi-automated production wheel building process in China:

I also wanted to mention several spoke length calculators I utilized when figuring out what spoke lengths I needed for each wheel/hub combination. Here is an excellent Java applet that did the trick.

I double checked my spoke length calculations using Damon Rinard's SPOCALC spreadsheet:

Following Sheldon's wheel building instructions, I started with the 'key spoke', directly next to the valve hole:

Next, I laced all the trailing spokes for that side of the hub:

Now, I flip the wheel over and lace the trailing spokes for the opposite side of the hub. Note that I've also started lacing the leading spokes (crossing 3 times over the trailing spokes):

Now I lace the leading spokes on both sides of the hub, remembering (for the most part) to cross over the trailing spokes 3 times. The wheel is completely laced!

...and goes into the truing stand for tightening up and truing.

It took me quite a while to get the wheel trued to my satisfaction. I'm sure most of it was due to my inexperience, but I took my time and followed the advice on the website and in Zinn's book. While lacing the wheels, I lubricated the threads of each spoke with Phil's Tenacious Oil before I threaded the spoke nipple on. I'm sure this made tightening the nipples easier and helped prevent thread galling, though I'm sure I stressed several spoke nipples during this process. I gradually tightened each spoke, up to one turn at a time, until I started to build tension in the wheel. Then, I began the process of rotating the wheel and alternately tightening and loosening spokes until most of the waviness disappeared...meaning the wheel was reasonably true. Two other tools which proved invaluable: a spoke tension meter and a dishing stick. I used the spoke tension meter to ensure the spokes were uniformly tensioned, and the dishing stick to make sure the hub and rim were centered. Of course, I needed to make adjustments to the dishing, and re-trued the wheel. All the while, I pre-stressed the spokes by grabbing groups of 4 spokes (2 per side), and squeezing.

The finished product:


It was time consuming and took several hours, however, I thoroughly enjoyed myself. This build really helps me understand how wheels are constructed and assembled. A bike wheel is something you really don't think about so much...just get on the bike and pedal. If something happens, haul it to your LBS and let them sort it all out. Nothing wrong with that. But it's really nice to be able pick out your own components, build the wheel you really want and be able to say 'Yeah, I built those wheels myself!'
-Dwight

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