A hearty amen. When going through engineering school we primarily used metrics and even when I worked in design in industry. It sure did make the calculations easier. Heres a rough chart for you: 1 = 25 mm (25.4) 3/4 = 19 (19.1) 1/2 = 13 (12.7) 1/4 = 6 (6.35) 1/8 = 3 (3.175) 1/16 = about 1.5 (1.6) 1/32 = about 1 (.8) Dean Dean May cell 812.239.3359 PianoRebuilders.com 812.235.5272 Terre Haute IN 47802 _____ From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf Of Jurgen Goering Sent: Monday, February 04, 2008 11:53 PM To: pianotech at ptg.org Subject: Re: Regulating Without Specs At the risk of opening a large can of worms and an even larger debate, I think this is perfect example of why going metric (like Dale Erwin demonstrated) is such an elegant mode of transport through exercises such as these. Mixing fractions with decimal inches may work in this prepped example, but the numbers are hardly ever so fortuitous. I heartily suggest to all technicians to immerse themselves in millimeters, stop converting to inches, buy metric rulers, calipers and whatever other measuring tools they need and discover the brilliant ease of working in that system. ducking for cover... Jurgen Goering On Feb 4, 2008, at 19:20, pianotech-request at ptg.org wrote: snip... Lets just say you want something typical like a 3/8 key dip, 1/8 letoff, and .050 aftertouch. (Later Ill show the equations for solving for different variables) Given the 3/8 key dip (.375) and the .050 aftertouch, we subtract aftertouch from key dip and know then that we have .325 of useable key dip to move the hammer. How far will it move? It will move 5xs the amount of keydip. 5 x .325 = 1.625. But thats not the hammer blow distance, because we havent accounted for letoff. If we want 1/8 (.125) letoff, we need to ADD that to the hammer travel of 1.625, so the blow distance is then 1.75, or 1 ¾. ...snip... OK, Lemme know whatcha think! John Dorr, RPT -------------- next part -------------- An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/20080205/092b7ae5/attachment.html
This PTG archive page provided courtesy of Moy Piano Service, LLC