[RASMB] Stiff equilibrium centrepieces

[John Philo]

Andrew and RASMB,

I often find that over time the centerpieces become too snug in the
housings, although for me this is more common with the velocity ones. I'm
not sure exactly what causes this problem. I think in part it is a true
swelling of the epoxy resin with water (most epoxies will do this to some
extent), since it seems to get a bit less when they sit dry for long
periods. At least for velocity centerpieces there also seems to be some
distortion over time (if you put a micrometer on the outside you will see
they are no longer perfectly round). 

My solution is simply to remove a little resin from the outside with a fine
sandpaper or carborundum paper. I usually use a 320 grit carborundum paper
(available in the US at any hardware store).

John Philo
Alliance Protein Laboratories


-----Original Message-----
From: rasmb-admin at server1.bbri.org [mailto:rasmb-admin at server1.bbri.org] On
Behalf Of Leech, AP
Sent: Wednesday, November 17, 2004 8:05 AM
To: rasmb at server1.bbri.org
Subject: [RASMB] Stiff equilibrium centrepieces


----------------------------------------------------------------------------
------
The older archived RASMB emails can be found at:
http://rasmb-email.bbri.org/rasmb_archives
and current archives at http://rasmb-email.bbri.org/pipermail/rasmb/
Search All the Archives at: http://rasmb-email.bbri.org/rasmb_search.html
----------------------------------------------------------------------------
------

Hello all from the gloomy north of England,

I'm having some trouble with my equilibrium centrepieces - they are getting
more and more tight in the housings. I don't think we are doing anything
unusual with them - they are washed carefully in dilute decon, water and
finally rinsed with ethanol and left to dry. There is no obvious deposit or
change to the plastic (charcoal filled epon). Velocity centrepieces seem to
fit ok in the housings so I don't think they are the problem.

Has anybody had the same difficulty, and even better, does anybody have a
remedy for obstinate centrepieces?

Many thanks,

Andrew

-- 
Dr Andrew Leech                   *  Laboratory Manager
Technology Facility               *  Molecular Interactions Laboratory
Department of Biology (Area 15)   *  Tel   : +44 (0)1904 328723
University of York                *  Fax   : +44 (0)1904 328804
PO Box 373,  York  YO10 5YW       *  Email : apl3 at york.ac.uk
_______________________________________________
RASMB mailing list
RASMB at rasmb-email.bbri.org
http://rasmb-email.bbri.org/mailman/listinfo/rasmb