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<DIV><STRONG><FONT size=2 face=Arial>Dear All involved,</FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2 face=Arial></FONT></STRONG> </DIV>
<DIV><STRONG><FONT size=2 face=Arial>I have tried PTFE tape also and find, as
John suggests, that it works well on jars with lids that are getting
past-their-best and would normally need replacing. However it does string
together and fall apart when the jar is opened again and the time saved in
having to replace it each time might well justify purchasing new jars anyway.
</FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2 face=Arial>However, I recall the Mmes Steigerwald and
Laframboise tested some tape by 3M back in the 1990s that went around the
outside edge of the jar seal and was effective. I know that this has since
been superseded by something else...?</FONT></STRONG></DIV>
<DIV><STRONG><FONT size=2 face=Arial></FONT></STRONG> </DIV>
<DIV><STRONG><FONT size=2 face=Arial>With all good wishes, Simon.
</FONT></STRONG></DIV>
<DIV> </DIV>
<DIV><STRONG><FONT size=2 face=Arial>Simon Moore MIScT, RSci, FLS,
ACR<BR>Conservator of Natural Sciences and Cutlery Historian,<BR><A
href="http://www.natural-history-conservation.com">www.natural-history-conservation.com</A>
<BR></FONT></STRONG></DIV>
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style="BORDER-LEFT: #000000 2px solid; PADDING-LEFT: 5px; PADDING-RIGHT: 0px; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="FONT: 10pt arial; BACKGROUND: #e4e4e4; font-color: black"><B>From:</B>
<A title=simmons.johne@gmail.com href="mailto:simmons.johne@gmail.com">John E
Simmons</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=prc44@drexel.edu
href="mailto:prc44@drexel.edu">Callomon,Paul</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Cc:</B> <A title=nhcoll-l@mailman.yale.edu
href="mailto:nhcoll-l@mailman.yale.edu)">NH-COLL listserv
(nhcoll-l@mailman.yale.edu)</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Saturday, January 11, 2014 2:34
AM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: [Nhcoll-l] PTFE tape on
jars</DIV>
<DIV><BR></DIV>
<DIV dir=ltr>
<DIV>
<DIV>Paul,<BR></DIV>Whether or not the Teflon (PTFE) plumber's tape helps will
depend on quality of the closures on the jars. If the closures are made of
good plastic (such as flexible polypropylene) or metal that is not oxidized,
and have a good liner (e.g., a Teflon liner or in the case of metal lids, a
compressible gasket around the inner edge) but the threads of the jar a a bit
deep or the lid fits a bit loose, the tape can help by closing the gap between
the jar and the lid. If you have a good quality lid that fits tightly on the
jar, then its probably not worthwhile to use the tape. If you have lids that
have tiny perforations (e.g., metal lids with micro-oxidation points) or
plastic that is very thin or has microscopic cracks, then the tape probably
won't help.<BR><BR>There is an easy way to test whether or not the tape
application improves your jar/lid combination. Fill a number of jars with
storage strength preservative fluid (no specimens!) and close some with the
Teflon tape and some without. Either mark the fluid levels on the outside of
the jar with a grease pencil, or better yet, weigh each jar. Put the jars in a
water bath and heat it to around 40-50C for a couple of weeks, then check the
amount of remaining fluid in the jars and
compare.<BR><BR></DIV>--John<BR><BR></DIV>
<DIV class=gmail_extra><BR clear=all>
<DIV>John E. Simmons<BR>Museologica<BR>128 E. Burnside Street<BR>Bellefonte,
Pennsylvania 16823-2010<BR><A href="mailto:simmons.johne@gmail.com"
target=_blank>simmons.johne@gmail.com</A><BR>303-681-5708<BR><A
href="http://www.museologica.com"
target=_blank>www.museologica.com</A><BR>and<BR>Adjunct Curator of
Collections<BR>Earth and Mineral Science Museum & Art Gallery<BR>Penn
State University<BR>University Park, Pennsylvania<BR>and<BR>Lecturer in
Art<BR>Juniata College<BR>Huntingdon, Pennsylvania<BR></DIV><BR><BR>
<DIV class=gmail_quote>On Fri, Jan 10, 2014 at 4:48 PM, Callomon,Paul <SPAN
dir=ltr><<A href="mailto:prc44@drexel.edu"
target=_blank>prc44@drexel.edu</A>></SPAN> wrote:<BR>
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class=gmail_quote>
<DIV lang=EN-US vlink="purple" link="blue">
<DIV>
<P class=MsoNormal>Folks,<U></U><U></U></P>
<P class=MsoNormal><U></U><U></U> </P>
<P class=MsoNormal>At least 20 years ago (before my time here), white
plumbers’ tape was wrapped around the edge of the lids and onto the sides of
all the bottle and jars in a certain section of our alcohol collections.
This is the PTFE tape that plumbers use to seal threads; it is thin, soft
and non-adhesive. Presumably the idea was to provide a secondary vapor
barrier in addition to the jar lid seal. <U></U><U></U></P>
<P class=MsoNormal>We are now doing long-overdue major maintenance on this
collection, and are trying to assess the efficacy of this tape. I’d be very
interested to hear from anyone who (a) has used it and can show it works (b)
has used it and can show it doesn’t work, or (c) who considered using it but
decided not to, and why.<U></U><U></U></P>
<P class=MsoNormal><U></U><U></U> </P>
<P class=MsoNormal><U></U><U></U> </P>
<P style="BACKGROUND: white" class=MsoNormal><B><SPAN
style="FONT-SIZE: 10pt">Paul Callomon</SPAN></B><SPAN
style="FONT-SIZE: 10pt"><BR><I>Collection Manager, Malacology, Invertebrate
Paleontology and General
Invertebrates</I></SPAN><SPAN><U></U><U></U></SPAN></P>
<DIV style="TEXT-ALIGN: center; BACKGROUND: white" class=MsoNormal
align=center><SPAN style="FONT-SIZE: 10pt">
<HR align=center SIZE=2 width="100%">
</SPAN></DIV>
<P style="BACKGROUND: white" class=MsoNormal><B><SPAN
style="FONT-SIZE: 10pt">Academy of Natural Sciences of Drexel University,
Philadelphia</SPAN></B><B><SPAN
style="FONT-SIZE: 10pt"><U></U><U></U></SPAN></B></P>
<P style="BACKGROUND: white" class=MsoNormal><SPAN
style="FONT-SIZE: 10pt">1900 Benjamin Franklin Parkway, Philadelphia PA
19103-1195, USA</SPAN><SPAN style="FONT-SIZE: 10pt"><BR><I><A
href="mailto:callomon@ansp.org" target=_blank><SPAN
style="COLOR: blue">callomon@ansp.org</SPAN></A> Tel <A
href="tel:215-405-5096" target=_blank value="+12154055096">215-405-5096</A>
- Fax <A href="tel:215-299-1170" target=_blank
value="+12152991170">215-299-1170</A></I></SPAN><SPAN
style="FONT-SIZE: 12pt"><U></U><U></U></SPAN></P>
<P
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