Quote:
Originally Posted by guyintense
Thanks to Gerd Schraner's The Art of wheel building.
One of the best books on the subject.
There are a number of popular methods of stressrelieving wheels, some gentler than others. Banging the spokes with your Doc Martens is definitely a case of overkill. The simplest method is to do the job on the workbench. Place the wheel on the bench in such a way that it rests on the axle and the 6 o'clock position of the rim. Using your left hand in the 9 o'clock and your right hand in the 3 o'clock position press the wheel in steps of approximately three spokes down towards the bench. When this side has been pressed, turn the wheel over and repeat on the other side. You should be able to hear the spokes settling. Re-true the wheel and repeat the pressing stage again until the wheel needs no more retruing. The wheel "stands" at last?
This need repeating, re-true the wheel and repeat the pressing stage again until the wheel needs no more retruing.
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This method can be used to eliminate spoke wind-up, but it does a poor job of stress-relieving. Because most rims have a relatively low lateral stiffness, pressing on localized points on the rim causes little increase in tension on the spokes - the main affect is for the rim to bend laterally and decrease tension in the spokes opposite the side being pushed. The more flexible the rim, the less effective this method will be for the momentary over-stressing required for stress-relieveing
Spoke stress-relieving by with a lateral load is only sure to be effective if the rim is rigidly supported. For example, Bontrager uses a table with a round hole just smaller than the rim. A wheel is laid on the table over the hole so that rim is centered around the hole (and the spokes and hub dangle in the middle of the hole), and then the upward projecting end of the axle is pressed downward, increasing the stress on the spokes below the rim uniformly, stress-relieving them.
Without a special table, the best way to stress relief is by squeezing or levering pairs of spokes. This loads the rim in it's stiffest modes (circumferentially and radially), allowing significant tension increases in the spokes being squeezed/levered. It is best to squeeze/lever pairs of spokes that are adjacent but on opposite sides of the wheel, to balance out the lateral bending loads on the rim:
