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<div class="moz-cite-prefix">Thanks, Elton.<br>
<pre class="moz-signature" cols="72">Elton Smith
Jefferson Lab MS 12H5
12000 Jefferson Ave STE 16
Newport News, VA 23606
(757) 269-7625
(757) 269-6331 fax </pre>
On 12/18/12 10:21 AM, iñaki wrote:<br>
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<blockquote
cite="mid:CAAKhTvLcVtXx4RMB5OgF-1hvFM=smj8bGR4Lxt2uPc07WXmEhw@mail.gmail.com"
type="cite">Dear Elton,
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</div>
<div>Regarding your question, How we are taking the measure of
length of a lightguide? <font color="#222222" face="arial,
sans-serif">I would like to explain you the procedure of the
dimensional control of the length, and some consideration in
the machining process to prevent over size.</font></div>
<div><font color="#222222" face="arial, sans-serif"><br>
</font></div>
<div><font color="#222222" face="arial, sans-serif">1.- Machining
process, the cnc programming of the milling machine is set to
80.08 [mm]. We are only 80 microns over the nominal size
because the polishing of mppc face and fiber face need less
time (amount of removed material) to be polish. Also, as we
use a jig to machining the sixth face (fiber face) the length
depend on how much precision the jig and lightguide is
mounted. The tolerance of this is (47-8) microns.</font></div>
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</div>
<div>2.- Measurement, after polishig process every light guide is
measure with a caliper and it is checked if it is inside
tolerance or not. <font color="#222222" face="arial, sans-serif">Pieces
out of tolerance are sent to reprocess, in some case they are
machining again over the length otherwise</font> only must be
polish.</div>
<div><font color="#222222" face="arial, sans-serif"><br>
</font></div>
<div><font color="#222222" face="arial, sans-serif">Thanks,</font></div>
<div><font color="#222222" face="arial, sans-serif">iñaki</font></div>
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