I have a let-off driver made to fit in a power screwdriver like Webb Philips sells. I turn the screws up until the button falls off and further so that just the very tip protrudes from underneath the rail. I have a Steinway hammer flange that has a hole drilled through the screw hole just large enough to accept a new let-off button. I insert the new button and fit the flange to the underside of the rail and so that the point of the screw is in the drilled hole. I then use the power screwdriver to drive the screw into the button until it spins against my finger pressure on the felt. I remove the slaignment tool and drive the screw a little further into the button. This method will work for a regular let-off rail except the alignment took needs to be flat instead of scalloped. I have not had any trouble with loose screws yet. If I thought I would have trouble I would dab a TINY amount of CA glue on the threads and let it set then screw the buttons on the slightly enlarged screws. Newton nhunt@rci.rutgers.edu
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