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<p class="MsoNormal"><span style="color:#1F497D">Some years back I had some difficult VCR’s seal well with Teflon VCR gaskets.<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:9.5pt;line-height:115%;font-family:"Arial",sans-serif;color:black">Dr. Mark J. McCollum<o:p></o:p></span></p>
<p class="MsoNormal"><span style="font-size:9.5pt;line-height:115%;font-family:"Arial",sans-serif;color:black">Principal Research Engineer<br>
<span style="background:white">Nick Holonyak, Jr. Micro and Nanotechnology Laboratory 2260<o:p></o:p></span></span></p>
<p class="MsoNormal"><span style="font-size:9.5pt;line-height:115%;font-family:"Arial",sans-serif;color:black;background:white">Grainger College of Engineering<o:p></o:p></span></p>
<p class="MsoNormal" style="margin-bottom:12.0pt"><span style="font-size:9.5pt;line-height:115%;font-family:"Arial",sans-serif;color:black;background:white">University of Illinois at Urbana-Champaign</span><span style="font-size:9.5pt;line-height:115%;font-family:"Arial",sans-serif;color:black"><br>
<span style="background:white">208 North Wright Street</span><br>
<span style="background:white">Urbana, IL 61801</span><br>
</span><span style="font-size:9.5pt;line-height:115%;font-family:"Arial",sans-serif;background:white">217-300-5181</span><span style="font-size:9.5pt;line-height:115%;font-family:"Arial",sans-serif;color:black"><br>
<span style="background:white">email: </span></span><span style="font-size:9.5pt;line-height:115%;font-family:"Arial",sans-serif;background:white"><a href="mailto:markjmcc@illinois.edu"><span style="color:blue">markjmcc@illinois.edu</span></a><span style="color:black"><o:p></o:p></span></span></p>
<p class="MsoNormal"><o:p> </o:p></p>
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<b>From:</b> labnetwork <labnetwork-bounces@mtl.mit.edu> <b>On Behalf Of </b>Mac Hathaway<br>
<b>Sent:</b> Wednesday, August 11, 2021 11:28 AM<br>
<b>To:</b> labnetwork@mtl.mit.edu<br>
<b>Subject:</b> [labnetwork] Cleaning up/ reconditioning VCR seals?<o:p></o:p></p>
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<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal" style="margin-bottom:12.0pt">Hello All,<br>
<br>
I'm wondering if anyone has ever developed a scheme for polishing or reconditioning VCR sealing surfaces. Obviously, buying a new one is the best approach, but some of our fittings are rather expensive or hard to come by, and some technique for cleaning up
mild wear or whatnot would be handy. And of course, this would not be applied to toxics.<br>
<br>
I leak test these down to 1E-12 torr-liter/sec, so that would be my goal. I imagine coaxial spinning of the fitting surface would be best (not hand-held), but what final grit would be needed. Is electropolishing absolutely necessary to get a good seal? This
would be very light polishing, not enough to flatten the bead of the seal.<br>
<br>
Any trick to keeping the polished particles out of the bore, or just an ultrasonic clean at the end?<br>
<br>
If it's impossible, that's good to know, as well.<br>
<br>
Thanks,<br>
<br>
<br>
Mac<br>
<br>
<span style="font-size:12.0pt;line-height:115%"><o:p></o:p></span></p>
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<p class="MsoNormal" style="margin-bottom:0in;margin-bottom:.0001pt"><span style="font-size:12.0pt;line-height:115%;font-family:"Times New Roman , serif",serif">Mac Hathaway</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-bottom:0in;margin-bottom:.0001pt"><span style="font-size:12.0pt;line-height:115%;font-family:"Times New Roman , serif",serif">Senior Process and Systems Engineer</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-bottom:0in;margin-bottom:.0001pt"><span style="font-size:12.0pt;line-height:115%;font-family:"Times New Roman , serif",serif">Harvard Center for Nanoscale Systems</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-bottom:0in;margin-bottom:.0001pt"><span style="font-size:12.0pt;line-height:115%;font-family:"Times New Roman , serif",serif">11 Oxford St.</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-bottom:0in;margin-bottom:.0001pt"><span style="font-size:12.0pt;line-height:115%;font-family:"Times New Roman , serif",serif">Cambridge, MA 02138</span><o:p></o:p></p>
<p class="MsoNormal" style="margin-bottom:0in;margin-bottom:.0001pt"><span style="font-size:12.0pt;line-height:115%;font-family:"Times New Roman , serif",serif">617-495-9012</span><o:p></o:p></p>
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<span style="font-size:12.0pt;font-family:"Times New Roman , serif",serif"> </span><o:p></o:p></p>
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