Dear Listers,

We're encountering a problem with our gasbench measuring needle. It's  
clogging every 2 days or so with usually single but sometimes multiple  
pieces of septa. We run carbonates (acidified by hand), primarily, as  
well as waters. When the needle isn't clogged we get exceptional  
precision using carefully weighed sample sizes. Are we tightening the  
exetainer caps too tight? Not tightly enough? I have tried different  
needle tip shapes. The exetainer/cap/septa product code is 9RK8W 12mL  
BORO x 100 from Labco, and the needle is the OEM thermo measuring  
needle.

Thanks!
Chris

_____________________________
Chris Maupin
Paleoclimate Lab, JGB 5.118
Jackson School of Geosciences
University of Texas at Austin
1 University Station C1100
Austin, TX 78712
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Stable Isotope Lab: 512-232-4184
http://www.ig.utexas.edu/people/students/maupin/