Originally Posted by
Drew Eckhardt
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You stress relieve by wearing a pair of work gloves and squeezing near-parallel pairs of spokes as hard as you can (except with very light or radially-laced rims). You can put an old left crank or brass drift in the spokes where they cross and twist them around each other.
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In addition to this I take the knob ball end of a large Sears Craftsman screwdriver handle and jam it into the triangular intersections of crossing spokes from both above and below. I think I picked that tip up from Jobst Brandt's book, but I don't remember.