The most sensitive test I know is to move the key up and down at the back end of the key. If sluggishness occurs you will feel it there. Before enbarking on any other course I recommend polishing the key pins with "Flitz" which is a superior metal polish. After polishing the pins, front and center, lubricate them with a powdered teflon lubrican call "Slide All", available from hardware stores and made by Bordons. Lubricate the bushings well and replace the keys, one at a time, and make each one fit properly. There are three places sluggishness can occur; 1 Is the front rail bushing. Check that the front rail pin is parrallel to the sides of the keys. Check that the bushings go no further into the key than 3/16" or 1/4". If they go further you will need to cut out the excess with a hobby knife with a chisel pointed blade. Using key easing pliers gently crush the wood under the bushing to VERY slightly enlarge the opening. There should be about .3mm to .5mm side play at this point. 2 The center rail bushings need also to be check for free movemnt of about .3mm. 3 The balance pin hole at the bottom of the key should allow the key to fall back into it's rest position slowly but assuradly. Easing is done with a flatten tapered tool designed for the purpose. Finally recheck all points again. Over doing easing is very distructive and is not normally recoverable. Properly done this is a one time operation unless you have SEVERE humidity problems. Newton nhunt@jagat.com
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