The explanation I got was as I mentioned. The arc on which the capstan travels is such that the capstan leaning slightly forward puts it more in a line tangent to that arc. The capstan heal contact surface is then set perpendicular to the capstan. That creates less sliding motion, less friction and greater efficiency in terms of travel. I suppose that means you could theoretically have an action with better mechanical advantage (leverage) and yet minimize the trade off in terms of having to increase dip or decrease blow distances to compensate. That part is my own musing, however. I don’t recall whether there was a detailed discussion in the archives or not on this particular issue. The relative ratios of the key and shank were somewhat altered as well, as I recall. The knuckle on those actions was hung, I believe, at 20mm. It was quite a heavy hammer and an adjustable wippen assist spring was also used. But this is digressing a bit. I’m sure Ron will comment. David Love www.davidlovepianos.com From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf Of PAULREVENKOJONES at aol.com Sent: Saturday, March 14, 2009 3:07 PM To: pianotech at ptg.org Subject: Re: [pianotech] key position at rest David: Recalling would presuppose a calling! :-) This bit about Ron Overs' action design is news to me. Does Ron offer (is this really old news?) insight into his reasoning and does he have demonstrably measurable results? If this is an archive matter, just say so, and I'll do the work! :-) Thanks, Paul In a message dated 3/14/2009 5:03:38 P.M. Central Daylight Time, davidlovepianos at comcast.net writes: Theory should be that the more the capstan is in line with a line drawn tangent to the arc on which it travels and the angle of the wippen heal is perpendicular to that line, the less sliding, the greater the wippen speed and the less friction. You might recall that on the Over’s action (Ron can correct me if I’m wrong) that the capstan angles slightly forward and the angle of the wippen cushion is slightly back, just the reverse of what you find on the older style pianos with angled heals and capstans. David Love www.davidlovepianos.com From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org] On Behalf Of PAULREVENKOJONES at aol.com Sent: Saturday, March 14, 2009 2:48 PM To: pianotech at ptg.org Subject: Re: [pianotech] key position at rest In a message dated 3/14/2009 4:14:35 P.M. Central Daylight Time, ricb at pianostemmer.no writes: The angled capstan idea was dropped years ago but was common enough around the turn of the century... 1900's. I'm really not sure what they were thinking about when they did that, but even S&S had them for a while. Ric: Correct me if I'm wrong on this (as if you wouldn't), but my understanding for a long time has been that the angled capstans actually are advantageous to leverage and friction. Inquiring minds really do want to know. Cheers... Paul _____ A Good Credit Score is 700 or Above. See <http://pr.atwola.com/promoclk/100126575x1220439616x1201372437/aol?redir=http:%2F%2Fwww.freecreditreport.com%2Fpm%2Fdefault.aspx%3Fsc%3D668072%26hmpgID%3D62%26bcd%3DfebemailfooterNO62> yours in just 2 easy steps! _____ A Good Credit Score is 700 or Above. See <http://pr.atwola.com/promoclk/100126575x1220439616x1201372437/aol?redir=http:%2F%2Fwww.freecreditreport.com%2Fpm%2Fdefault.aspx%3Fsc%3D668072%26hmpgID%3D62%26bcd%3DfebemailfooterNO62> yours in just 2 easy steps! -------------- next part -------------- An HTML attachment was scrubbed... URL: <http://ptg.org/pipermail/pianotech_ptg.org/attachments/20090314/a8157041/attachment.html>
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