Counter-intuitive User-interface
The fulcrum usually travels over a range of approximately 0.75 metres (30 inches), and is set by way of a knob that is approximately 0.35 m (14 in) in diameter. To stiffen the spring (as if tightening it), the knob is usually turned counter clockwise. This is counter intuitive, since usually things are tightened by turning clockwise. Additionally, if standing on the springboard, it is difficult to push the wheel with the foot, because the top of it needs to turn the other way from the way it moves. This is because the gearlike mechanism (usually a "soft gear" made of rubber) is on the board and not the base, so the wheel pivots against the board when rotated. Thus users often need to bend down and set the wheel, or come down from the board to set the wheel. Thus it would be much better if the gearing were on the base so that the wheel could be pushed with the foot, but tradition (consistency from board to board) dictates maintaining a "backwards" convention.
- Note - Standing behind or in front of the knob, rather than directly above it, will give you better leverage to move the fulcrum. This is accomplished by holding on to the hand rails and leaning the body a few degrees, then placing your foot as low as possible on the knob. In this way, it is possible to move even the most difficult fulcrum.
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