This is not as bad as it may seem. The screw should be a bit difficult to adjust, this is normal.
You want to adjust the screw in small increments then test the panning tension of the Head exactly as follows:
1. Mount the Head onto a tripod and tighten normally (no need to over-tighten) without a lens or camera attached.
2. Firmly tighten the top swing arm adjustment knob (no need to over-tighten) and mount the platform.
3. Loosen the side panning tension adjustment knob (do not unscrew all the way).
4. With the Wimberley Head upright casting directly in front of you, give the curved bottom of the upright a firm slap with the palm of your hand in a clockwise direction.
5. If the Head does not move much, or less than 90 degrees, you should loosen the center screw a bit more.
6. If the Head upright swings past 90 degrees in movement, the screw is too loose and needs to be tightened.
7. Keep adjusting the screw until you can slap the upright and it comes to rest at about 90 degrees (should be to your left, perpendicular to it’s starting point).
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