Mark's show & tell
Mark Stonich had 4 wheels to build, and had just been using bent nails and a fork for truing, so he built a precision wheel truing jig. Really simple, since he didn't need supports on both sides, because he always uses a dishing gauge. It's just a steel bar with slots cut for the axels of different sized wheels and a bolt with 2 dial indicators mounted to it. He added a base, but you can just clamp the bar in a vise, or with a piece of tubing added, in a bike stand. Mark got within less than 5 thousandths in a few minutes. He also built 2 wheels within 0.006" with USED rims.
He'll never build another wheel without dial indicators. It's SO MUCH FASTER, he figures if he does a couple more wheels he will have saved more time than he spent building the stand.
Mark explained that dishing gauges are very easy to make - He'll probably even add a dial indicator (Enco has them for $8.49) to his next one.
He gave a quick tutorial on building light yet durable wheels.- Don't try and save money at the rim. Heat treated rims don't distort at the spoke holes, so stay true longer. Deep section rims can be very stiff, with little extra weight. Double-butted spokes whenever possible. Light spokes and a stiff rim are much tougher than heavy spokes and a light rim.
Mark is working on a new long wheelbase recumbent. His goal is to see how light he can make it without using any exotic or expensive components. The plan is to only use as much metal as necessary. He even bored out the ID of his BB shell leaving only a few threads at each end.
Lightweight wheels - A stiff Velocity rim allowed a front wheel with only 12 spokes. Even went to Penn Cycle where they can cut short 15 ga. spokes, instead of using Luke's machine to cut 14 ga.
Rear wheel has no dish, offset is taken care of in the rear dropouts. This allowed use of DT Revolution spokes on both sides. With very short butts, and only 1.5mm center section they weigh 137g per wheel, vs 213g for straight 14ga. The only way to get lighter would be Titanium spokes at 126g, but at well over 3 times the cost.
Mark's lightweight fork uses old style Reynold's 531 blades. Though a slightly heavier than modern stuff, the 25 year old blades have lots of rake and a much smaller diameter lower section than any available now. Because the front wheel will give a stiff ride, with it's 120psi tire, a fork that flexes a bit is a good thing. Using tubing instead of a fork crown saved an ounce. About 1/3 of the metal has been filed and ground off the Shimano dropouts, but the blades are so slender they still look large. Steerer tube is 0.058" straight gauge saving even more weight. Right now it's under 1.5 lbs, and about 4" of steerer will be cut off.
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