Don wrote: >I believe it is a legacy from plumbers. I'd try a plumbers supply store for >a tap and die. Failing that contact Mike Swendson in Calgary. He makes >tuning levers. I've copied Mike on this too so maybe he'll be able to shed some light. But tuning lever makers often seem to be more concerned with the lever components and get their tips & heads from a supplier as standard parts (hmm) so they would avoid the problem. I haven't been able to come up with any current or archaic standard thread size with a 30tpi. The finest plumbing threads (taper or parallel) seem only to go to 27 or 28tpi depending on the system, but including the archaic ones, so I can't see it being a plumbing legacy (and what's the connection between tuning lever making and plumbing anyway). This situation begs the questions when was this standard adopted for tuning tips? and why? and why is it still so ubiquitously used for tuning lever tips? Is this just yet another example of the piano industry being anal? As for the how....are Hale tips made by an army of lathists running their lead screws through the night in sweatshops or are special taps and dies exchanged for large sums in back alleys. Maybe a subject for industrial espionage? Maybe there's some sort of secret handshake to get into the 30tpi club. Or maybe the size adopted as the most obscure one that would prevent the rabble from flooding the tuning tip market with cheap ripoffs and bringing down the value of tuning tip investments? Hmm. You'd think someone here would know at least some dirty tip thread rumours. Stephen -- Dr Stephen Birkett, Associate Professor Department of Systems Design Engineering University of Waterloo, Waterloo ON Canada N2L 3G1 Director, Waterloo Piano Systems Group Associate Member, Piano Technician's Guild E3 Room 3158 tel: 519-888-4567 Ext. 3792 fax: 519-746-4791 PianoTech Lab Room E3-3160 Ext. 7115 mailto: sbirkett[at]real.uwaterloo.ca http://real.uwaterloo.ca/~sbirkett
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