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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple><div class=WordSection1><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Indexing was a poor choice of words. Locating would be better – essentially something to keep both base circles concentric for fitting either for lapping or for mating together in the part’s final configuration. A lot of parts that I might make that have to align well might have a spigot on one half and a mating counterbore on the other.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>For lapping, I would think some sort of centerline guide would be useful to keep the two halves in the correct position. Lapping might be overkill? After all it’s not a Swiss watch! If your machined fit is good and you are relying on a captive sealing element like an o-ring – I would hope you are not going deep enough to extrude it through a 3 thou gap!!! </span><span style='font-size:11.0pt;font-family:Wingdings;color:#1F497D'>J</span><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'> <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>I’m sorry if I wasn’t paying very close attention – I’m just lurking on this group and your boring machine really caught my attention. <o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>I’m building a non-submersible steel boat (hopefully!) right now and may one day move onto something like this.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'>Tom<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:11.0pt;font-family:"Calibri",sans-serif;color:#1F497D'><o:p> </o:p></span></p><div><div style='border:none;border-top:solid #E1E1E1 1.0pt;padding:3.0pt 0in 0in 0in'><p class=MsoNormal><b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'>From:</span></b><span style='font-size:11.0pt;font-family:"Calibri",sans-serif'> Personal_Submersibles [mailto:personal_submersibles-bounces@psubs.org] <b>On Behalf Of </b>Private via Personal_Submersibles<br><b>Sent:</b> Monday, January 11, 2016 7:42 PM<br><b>To:</b> Personal Submersibles General Discussion <personal_submersibles@psubs.org><br><b>Subject:</b> Re: [PSUBS-MAILIST] taper fit up<o:p></o:p></span></p></div></div><p class=MsoNormal><o:p> </o:p></p><div><p class=MsoNormal>Hank, if you're down to 0.003 isn't it just a matter of putting lapping compound between the hatch and land, and rotating the hatch a bunch of times? I know it's heavy, but maybe with a big lever you can walk around like an 18th century seaman turning a capstan. <o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Best,<o:p></o:p></p></div><div><p class=MsoNormal><o:p> </o:p></p></div><div><p class=MsoNormal>Alec<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><p class=MsoNormal style='margin-bottom:12.0pt'><br>On Jan 11, 2016, at 7:01 PM, hank pronk via Personal_Submersibles <<a href="mailto:personal_submersibles@psubs.org">personal_submersibles@psubs.org</a>> wrote:<o:p></o:p></p></div><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><div><div><div id="yui_3_16_0_1_1452556512829_2594"><p class=MsoNormal style='background:white'><span style='font-size:9.0pt;font-family:"Helvetica",sans-serif;color:black'>Tom,<o:p></o:p></span></p></div><div id="yui_3_16_0_1_1452556512829_2594"><p class=MsoNormal style='background:white'><span style='font-size:9.0pt;font-family:"Helvetica",sans-serif;color:black'>Not sure what you mean about indexing. My original plan was to use the centre bore for the hatch release as a guide to rotate the hatch over the land with lapping compound. The problem with that idea is, the hatch has to make a few trips back to lathe and getting it back to the exact location is pretty tough. Then the centre is off a few thousandths. I am struggling with the final .003 I can't seem to get it closer. I think my lathe might be lacking the accuracy. I know,,,blame the tools ;-) <o:p></o:p></span></p></div><div id="yui_3_16_0_1_1452556512829_2594"><p class=MsoNormal style='background:white'><span style='font-size:9.0pt;font-family:"Helvetica",sans-serif;color:black'>I need to sleep on it, I have the blueing on the way. If it was easy, everyone would be doing it.<o:p></o:p></span></p></div><div id="yui_3_16_0_1_1452556512829_2594"><p class=MsoNormal style='background:white'><span style='font-size:9.0pt;font-family:"Helvetica",sans-serif;color:black'>Hank<o:p></o:p></span></p></div></div></div></blockquote><blockquote style='margin-top:5.0pt;margin-bottom:5.0pt'><div><p class=MsoNormal>_______________________________________________<br>Personal_Submersibles mailing list<br><a href="mailto:Personal_Submersibles@psubs.org">Personal_Submersibles@psubs.org</a><br><a href="http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles">http://www.psubs.org/mailman/listinfo.cgi/personal_submersibles</a><o:p></o:p></p></div></blockquote></div>
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