I had a well-meaning cohort who thought it would be prudent to clean all the rust off the tuning pin coils with WD40 and a wire wheel in a Dremel tool. It looked real pretty when he was done, but the pinblock was ruined. Pins that were already quite loose slipped their bonds and went WAAAYYY flat. The piano was untunable. It had already been doped AND treated with CA glue. The WD40 finished if off. Time for new block and restringing. Trouble is, it's a no-name mediocre 5-ft. grand. Barely worth it. --David Nereson, RPT <div class="gmail_quote">On Wed, Aug 22, 2012 at 3:28 PM, David Boyce <<a href="mailto:David@piano.plus.com" target="_blank">David@piano.plus.com</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> <div bgcolor="#FFFFFF" text="#000000"> Yesterday I visited a new client, a very nice family who have a 1912 Bechstein model 10 upright, straight strung. A music student lodges with the family during term time and they wanted the piano ready for him coming back. There had been another tuner some months ago. What, I mused aloud upon taking off the top panel, was the strange discoloration on the surface of the pinblock? I was then told that the previous tuner had used WD40, applying it to the tuning pin coils in case of any rust bonds. My inclination would be to keep WD40 or any similar lubricant a mile away from tuning pins. But hey, whadda I know? Perhaps this other guy is more up-to-date than I? What do you think folks? How "creepy" is WD40? Quite creepy, I think, judging by how it's crept all over and into the surface of the pinblock. And judging by how oily my fingers came to feel just from slight contact as I lifted the tuning lever from pin to pin. How badly is it likely to have crept down the tuning pins into the holes? The pins felt a little loose but not outrageously oleaginously so. Would CA treatment work, with WD40 present? Best regards, David. <a href="http://www.davidboyce.co.uk" target="_blank">www.davidboyce.co.uk</a> </div> </blockquote></div>