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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple style='word-wrap:break-word'><div class=WordSection1><p class=MsoNormal><b><span style='font-size:12.0pt;font-family:"Arial Black",sans-serif'>There are several articles on bolts on my site on the Technical page Miscellaneous Section<o:p></o:p></span></b></p><p class=MsoNormal><b><span style='font-size:12.0pt;font-family:"Arial Black",sans-serif'><o:p> </o:p></span></b></p><p class=MsoNormal><b><span style='font-size:12.0pt;font-family:"Arial Black",sans-serif'>John Sims<o:p></o:p></span></b></p><p class=MsoNormal><b><span style='font-size:12.0pt;font-family:"Arial Black",sans-serif'><a href="http://www.healey6.com/"><span style='color:#0563C1'>www.healey6.com</span></a><o:p></o:p></span></b></p><p class=MsoNormal><b><span style='font-size:12.0pt;font-family:"Arial Black",sans-serif'>Matawan, NJ<o:p></o:p></span></b></p><p class=MsoNormal><b><span style='font-size:12.0pt;font-family:"Arial Black",sans-serif'><o:p> </o:p></span></b></p><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b>From:</b> Healeys <healeys-bounces@autox.team.net> <b>On Behalf Of </b>Curtis Arndt<br><b>Sent:</b> Wednesday, December 23, 2020 10:54 AM<br><b>To:</b> Roger Grace <roggrace@telus.net>; Healey List <healeys@autox.team.net><br><b>Subject:</b> Re: [Healeys] Whitworth vs UNC<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>Here is an excerpt from one of my articles...<o:p></o:p></p></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>On Tue, Dec 22, 2020 at 1:48 PM Curtis Arndt <<a href="mailto:cnaarndt@gmail.com">cnaarndt@gmail.com</a>> wrote:<o:p></o:p></p></div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-right:0in'><div><p class=MsoNormal>The bolt is 5/16" BSW! Don't let anyone tell you different. <o:p></o:p></p><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Even my 45K original mil<span style='font-family:"Arial",sans-serif'>e '60 Bugeye </span>has its original 5/16" BSW bolt in the generator front plate. The problem arises since a 5/16" UNC bolt has the same tpi (threads per inch) as the 5/16" BSW bolt. The issue is that UNC has a thread pitch angle of 60<span style='font-size:12.0pt;font-family:"Segoe UI Symbol",sans-serif'>°</span> and Whitworth by definition is 55<span style='font-size:12.0pt;font-family:"Segoe UI Symbol",sans-serif'>°. </span><span style='font-family:"Arial",sans-serif'> The wrong bolt will never torque properly and will eventually wear the aluminum generator front plate.</span><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='font-family:"Arial",sans-serif'>Cheers,</span><o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><span style='font-family:"Arial",sans-serif'>Curt</span><o:p></o:p></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><div><p class=MsoNormal>On Mon, Dec 21, 2020 at 3:53 PM Roger Grace <<a href="mailto:roggrace@telus.net" target="_blank">roggrace@telus.net</a>> wrote:<o:p></o:p></p></div><blockquote style='border:none;border-left:solid #CCCCCC 1.0pt;padding:0in 0in 0in 6.0pt;margin-left:4.8pt;margin-right:0in'><div><div><p class=MsoNormal>My understanding is that they are close but not interchangeable ?<o:p></o:p></p></div><div><p class=MsoNormal>Thread angles are slightly different.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>For AH generator adjusting link is this 5/16 W or 5/16 UNC ?<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>At back of my mind think they should be Whitworth - think you told me that is why they come loose if you use UNC ?<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Finding it difficult to identify one from the other.<o:p></o:p></p></div><div><p class=MsoNormal>Any tips to do this welcome.<o:p></o:p></p></div><div><p class=MsoNormal>Have a definite W bolt and comparing to UNC can only see slight rounding of UNC ?<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Moss sent me a UNC bolt for this link - well that is what they called it ?<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Would appreciate your expert input.<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Regards,<o:p></o:p></p></div><div><p class=MsoNormal>Roger Grace<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div></div></blockquote></div></blockquote></div></div></body></html>