From: Jo Butler <pjgb@mrc-lmb.cam.ac.uk>
  To  : Joel Mackay , rasmb@alpha.bbri.org
  Date: Fri, 06 Apr 2001 10:08:46 +0100

Re: centrepieces again

Dear Joel,

We use the aluminium-filled epon centrepieces without the aluminium band 
and, although Beckman say only up to 55K for the double sector, I have done 
velocity runs at 60K, without unacceptable breakage rates for the 
centrepieces, and regularly overspeed my equilibrium runs to 55K to get the 
baselines.  If running at high speeds the one essential is to be 
particularly careful about getting the cell aligned radially, otherwise the 
septum is likely to break.

Jo

--On Friday, April 6, 2001 6:55 pm +1000 Joel Mackay 
<j.mackay@biochem.usyd.edu.au> wrote:

> hi all,
> Well, now that we have decided to replace one of our centrepieces rather
> than repair it, we have been faced with the perplexing situation that
> Beckman dont seem to have the same centrepiece. The part number we have
> (although apparently they have changed their part numbers recently) is
> 331430, and the centrepiece is epon filled with an aluminium band around
> it (it's not one of the all-aluminium ones). I was told when i inherited
> the XL-A from Greg Ralston that this centrepiece was OK up to 56K. Does
> anyone else have any of these centrepieces and have an idea if i can get
> hold of them. They have worked well for us as we do a lot of high-speed
> equilibrium work (up to 56K -  we have very small proteins!), and i have
> been told that the all-aluminium ones are a bit prone to leaking, so i am
> keen to get a replacement. Any wisdom gratefully accepted!
> cheers,
> joel
>
> *****************************************************************
> Dr Joel Mackay
> ARC Research Fellow
> Department of Biochemistry
> University of Sydney,
> Sydney, NSW 2006
> Australia
> ph +61-2-9351-3906
> fax +61-2-9351-4726
> WWW: http://www.biochem.usyd.edu.au/staff/mackay/
> Sydney Protein Group Website:
> http://www.biochem.usyd.edu.au/spg/
> ****************************************************************



P.J.G. Butler,
MRC Laboratory of Molecular Biology,
Hills Road, Cambridge, CB2 2QH, UK.
Tel. +44 (0)1223 402296