Hi Herb

You may be able to get the gas inlet cross piece assembly from MasCom in 
Germany. I'm not sure if they have a US agent but the message below is 
recently from their UK agent. I assume he was getting it from MasCom and 
not Thermo themselves.

http://www.mascom-bremen.de/html/en/0/index.html

Hello John

Price for gas valve assembly  p/n 1113980 is replaced by 1149300 is £733.35
plus delivery £16.00 and VAT
delivery is about 3 months.

We have made them up in-house before and if you wish to do this I can 
send you details.

Regards

John Hill
UCL Chemistry

Herbert Tobias wrote:
> Hello All,
>
> I was wondering if anyone knew the exact specifications for a flange,
> spacer, and gasket on the MAT 253 and where one can procure them.  It is
> for the inlet valve directly attached to the side of the MAT 253 ion
> source.  I did not remove it because we are currently using the system. 
> It is held by 4 bolts and has an OD of 1.413 inches.  I believe it is an
> ASA type, but I cannot find an OD dimension that matches when looking
> on-line.  Also, I know it probably seals with a gold gasket (dimension?). 
> I am hesitatnt in ordering something that seems nearly right because it
> could be some non-standard German design.  As usual, the thermo finnigan
> manual is sparse and cryptic with this information.
>
> The motivation is: I want to get a different valve setup at that point
> because the Thermo valve setup has issues such as promoting high water
> backgrounds when toggled and causing some tailing on continuous flow peaks
> (when compared to a MAT 252 with a different valve setup).
>
> Thanks,
> -Herb
>
> Cornell University
>
>
>
>