You might want to check for the tightness of the pin block screws. I have seen a few of these where the pin block was not tightly fitted to the plate flange and was rocking a little. After tuning half way up the scale the tension begins to shift to the other side and then the first side is out again. Go back and tune the first side and the other half has changed, etc, etc. Make sure the plate screws into the block are as tight as they can possibly be. Use a big screw driver with a squared shank and put a wrench on it. Hopefully any looseness will be fixed. Rob Goodale, RPT Las Vegas, NV
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