Hi Anthony, When I was a university tech, I had dozens of these MAFCO benches all over the campus. Of course tightening everything is the first thing to do. I found that the worst offenders were four large roundhead wood screws, one in each corner. There was a little brass linkage, 2-3 " long, connecting the wooden frame on which the legs are mounted, with the metal height-adjusting mechanism. These screw would very often be very loose, the threads nearly stripped, and the wood wallowed out so the screw would wobble quite a bit. A bit of a wobble in these four screws translates to considerable wobble of the seat. A bench in the condition, and pianists reaction to it, always created for me the mental image of a mechanical bull riding machine, mounted by a musician in tux and tails. My solution to the four loose striped screws was to replace them with 1/4"x20 carriage bolts with two nuts. The original screws are inserted from the inside. The carriage bolt go from the outside in. The second nut is a locking nut, allowing the first nut to be less than fully tightened, so the link can rotate freely. Frank Emerson
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