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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link="#0563C1" vlink="#954F72"><div class=WordSection1><p class=MsoNormal>Curtis,<o:p></o:p></p><p class=MsoNormal>Thank you for putting together such a definitive treatise on the fascinating history of British threaded fasteners and the industry’s conversion to U.S. standards. The British experience is a precursor to the U.S. slow walking conversion to ISO standards. Looking at Austin-Healey products, one might think that the Brits were more accommodating to having a variety of approaches than their U.S. cousins. Might be a cultural thing.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>I, we, would like to read a supplemental discussion of the relative merits of the 55 degree rounded roots and peaks thread design versus the U.S. standard of 60 degree with ‘V’ roots and peaks. What I remember from past discussions regarding the overall performance characteristics of modern thread designs; including thread stripping, pull out strength, and fatigue resistance favored Whitworth first, then U.S. standard, with ISO bringing up the rear. Is that your belief?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Will you possibly in a later effort describe the best uses of the various fasteners depending on the materials being joined, loads and their direction, vibration, load cycling, etcetera in selecting fine versus course thread; bolt shoulder, head, bearing surface and wrenching method, and the many other criteria that enter into fastener selection.<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>You added to the points to consider when judging a car’s concours ‘as born’ condition. Thank you. However, would you consider expressing your opinion as to which specific fastened joints a Healey owner might want to use a more modern substitute fastener to make a more reliable daily driver?<o:p></o:p></p><p class=MsoNormal><o:p> </o:p></p><p class=MsoNormal>Thank you again for your authoritative contribution.<o:p></o:p></p><p class=MsoNormal>Hap<o:p></o:p></p></div></body></html>