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You are about to embark on one of the most satisfying yet simple tasks in the bicycle craft. Building a wheel is only a matter of lacing the spokes in a pattern that places each one correctly between hub and rim, then tensioning and truing them to achieve wheel strength and alignment. Truing will take some time to learn well, but lacing should be no problem for any first-time wheel builder who uses well-matched parts and the foolproof procedure I'll describe in this article. Assuming you followed my advice in part one of this series (January 1986), you now have a desk top full of wheel components: a front and rear hub of decent quality, rims matched to the type of riding you're building the wheels for, and spokes of the correct length and gauge. Remember, assembly is greatly affected by the quality of the materials. Spokes that are not the same length, hubs that are twisted or eccentric, rims that are out of round or drilled erratically -- these things tremendously complicate the process. They can transform the straightforward task of wheel building into a first-class puzzle requiring years of experience to sort out. Avoid trouble by sticking to quality components. Once you are experienced, you'll have no trouble building a wheel while watching TV or talking with friends. But for now it's best to minimize distractions. Select a location with a convenient counter top, a stool or bench that allows your knees to be at seat height, and plenty of light. Set out your components and verify that they are exactly what you need. Now gather your tools: a spoke wrench that exactly fits the nipples, a screwdriver, a truing stand, and a dishing tool. (The last 2 tools aren't mandatory -- you can make do by using a suspended or upended bicycle -- but you really should have them if you are serious about becoming a good wheel builder.) Light oil will come in handy during tensioning, and a smooth-jawed plier may be necessary to prevent an extra tight spoke from winding up. The method that follows is only one of many successful and clever ways to assemble a wheel. It applies to "left-handed" rims (by far the most common type) and ensures that the finished wheel will be symmetrical. That is, each spoked hub flange will appear as a mirror image of its opposite. In the case of rear wheels, the "pulling" spokes will be oriented away from the derailleur when they're under tension, which minimizes damage if there should be contact during low-gear riding. In addition, the rim's valve hole will be located between parallel spokes for maximum accessibility. As a final touch, the logo on the hubs should be readable when you straddle the bike, and the rim labels should face to the right. Your first wheels deserve these features, which are minor but highly valued by experts. For building ease, the spokes are divided into 4 equal groups. Two groups, radiating in opposite directions, are inserted into each hub flange. (At the rim, you'll notice that spokes are in parallel sets of 4, each set consisting of one spoke each from the 4 spoke groups.) Let's begin to insert and connect the first group. If you wish to coat the spoke threads with a substance that helps resist loosening by vibration -- linseed oil is the old favorite -- do it now.
Separate your spokes into 4 groups (9 spokes per group for the standard 36-spoke wheel). Have a seat. Hold the hub in front of you with the axle vertical. If it's the rear hub, the threaded side should be down. If it's the front hub, the logo on the center part of the hub should read from top to bottom. Drop 9 spokes into the top flange, putting one in every other hole. For rear hubs this will be the left flange, and it should receive the longer spokes if you are building with 2 lengths to help achieve dish. Lay the rim on your thighs so it is horizontal. Position the valve hole opposite your stomach with the rim label upside down. Hold the hub in the center of the rim with the spokes hanging down. Select any spoke (which from now on will be referred to as the No.1 spoke) and put it through the first hole to the left of the valve hole. Attach its nipple a couple of turns. Notice that the rim's spoke holes are slightly offset; as you are looking at the rim on your lap, one hole is a little above the imaginary center line, the next is a little below, and they alternate that way around the rim. The hole you have put the first spoke into should be offset toward the top of the rim. Top holes are intended for spokes from the top flange. If you find that the first hole to the left of the valve hole is offset toward the bottom and the first one to the right of the valve hole is toward the top, you've got a rare "right-handed" rim and must make an adjustment.* Back to the hub, select the spoke immediately to the right of the No. 1 spoke. Leave 3 empty spoke holes to the right of the filled spoke hole in the rim (disregard the valve hole), then put the second spoke in the fourth hole. Again, this should be a hole that is slightly above the imaginary center line. Attach the nipple, then proceed to insert a spoke and its nipple into every fourth hole all the way around the rim. * To lace a "right.banded" rim, simply insert the No. 1 spoke into the second hole to the left of the valve hole. The first spoke of the second group should be half a flange hole closer to the valve hole than the No. 1 spoke. It should attach through the hole between the valve hole and the No. 1 spoke. Then continue lacing as described.
Flip the rim and hub so the unspoked flange is on top. This is the threaded side of a rear hub. Look carefully from directly above the top flange and notice that its holes do not line up with those of, the bottom flange: Prove it by dropping a spoke through a hole in the top flange -- it hits between two bottom-flange holes. Now comes the only tricky part of lacing a wheel. You must determine which hub flange hole gets the first spoke of the second group (spoke No. 10 overall). It will be a hole above the hole used by the No. 1 spoke. Since there are 2 possibilities, drop a spoke through each hole so they rest against the bottom flange. Make sure they are vertical. One will be just to the left of the No. 1 spoke, the other just to the right. The correct spoke is the one to the right. Put this No. 10 spoke into the first rim hole to the right of the No. 1 spoke. Attach the nipple. Proceeding around the flange, skip one hub flange hole and drop in another spoke. Put it into the rim, 4 holes away from the spoke that is next to it. Proceed until all 9 spokes of the second group have been installed. This time, do not flip the rim. Group 3 spokes are dropped through the bottom (first) flange of the hub. Again, these will be the longer spokes if you are using 2 lengths to dish a rear wheel. Fill all the empty holes. Now hold the rim vertical so these spokes hang by their elbows. (Help them if they're tight.) Lay the wheel on your lap with the group 3 spokes on top. Holding the rim still, twist the hub counter clockwise as far as you can. If done correctly, parallel spokes Nos. 1 and 10 will leave the rim pointing away from the valve hole, not across it. Group 3 spokes travel to the rim in the opposite direction of the group 1 spokes sharing the upper flange. The first group 3 spoke that's installed is the one that establishes the crossing pattern. Cross 3 is the standard. This means each spoke passes over 2 spokes and then under a third before entering its rim hole. Four cross means over 3: and under 1; 2 cross is over 1 and under 1. Don't overlook the first spoke cross, which occurs right at the edge of the flange. The crossing pattern is something that must be decided when you buy spokes because it is part of determining correct spoke length. To lace with the cross-3 pattern, select any group 3 spoke and direct it over 2 spokes and under 1. Do not cross any other spokes before putting it into the first available hole in the rim. Again, since you are working from the top flange, the correct hole will be a little above the imaginary center line. Loosely attach the nipple, then lace the next spoke. Don't worry if the spokes seem to be tight in the hub. It is a healthy sign. Tight-fitting spokes will receive plenty of support at their bend when they dig into the soft edge of the flange. That lessens the chance of them breaking. Group 4 is a repeat of 3. Without flipping the wheel, drop the remaining spokes into the open holes in the bottom flange. Hold the wheel vertical so the loose spokes hang down, then lay the wheel over with the group 4 spokes on top. Lace each one into the rim and attach the nipple a couple of turns. If you've made an error during the lacing this will be a most confusing stage, because the group 4 spokes will seem either too short or too long to fit correctly. Sometimes it is easier to disassemble and start over than backtrack to find the mistake. When all spokes are attached, sit back and admire your handiwork. You've just laced a wheel as well as any pro. Now mount it in a truing stand and put a drop of light lubricant between each nipple and the rim. (Avoid sulphur-bearing oils, because sulphur will degrade the brass from which most nipples are made.) Tighten every nipple with a screwdriver until only the last spoke thread is visible. If your spokes are a little short, it may be necessary to leave several threads showing at this stage -- make sure it's the same number for each spoke. For safety's sake, the nipples must be screwed on a minimum of 8 full turns when you've finished tensioning. Now that each spoke is adjusted to the same length as its neighbors, it's time to bend the spokes near their elbow so they fully conform to their direction. Do it by inserting a stout screwdriver shaft between two spokes, just under one of the crosses. Once in this triangle, lever the screwdriver so the handle end rests against the outside spoke and the blade end presses against the inside spoke. A gentle push will bend them into conformity. Go around the wheel "setting in" pairs. This procedure stabilizes the wheel by doing immediately what normally occurs during miles of riding. The life of each spoke is enhanced because each elbow bends less after it conforms to its path. Otherwise, it constantly tries to recover its original shape during riding and fatigues more quickly.
Success in wheel building depends to a great extent on the initial lacing and length-evening steps just described. Perform them carefully and the wheel can seem to fall into place. That's important, because when you're done, every spoke will bear a tension approaching 300 lbs. Compressive force in the rim will be measured in tons. Your decorative wire sculptures will be capable of high speeds, sharp cornering, and rapid decelerations. In the next instalment you will discover a simplified method of truing. By approaching this potentially confounding process in a new and scientific way, you will be able to produce even stronger and more reliable wheels.
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