Date: Tue, 27 Jan 2026 15:54:22 -0600
I have not attempted such a modification, but my general process with fills
is to clamp the tube from the fill port stack (left in your photo) using a
binder clip and vent from the opposite stack (right) the clamp forces all
of the gas to vent out of one stack.
_____________________________________
Todd Rappe
Minnesota NMR Center <nmr.umn.edu>
612-625-9147 (office)
651-321-TODD (rings office and mobile)
612-624-8892 (magnet lab)
On Tue, Jan 27, 2026 at 2:30 PM Vander Velde, David via groups.io wrote:
> Hi, I am now involved in managing a Bruker Ultrashield magnet (which I had
> previously done decades ago) after a period of managing Ascend magnets.
> Prior to the Ultrashield series, every magnet I worked with (Oxford or
> Spectrospin) had a cross piece connecting however many helium stacks there
> were, with a small one way valve on the single vent.. The Ultrashields came
> without this piece, with just Tygon tubing connecting the stacks to a
> similar one way valve. With the Ascend series, the cross piece came back,
> with a much more robust one way valve which can stay in place during helium
> fills. (pictures attached)
>
> I took care of Ultrashields for quite a while without understanding why
> the cross piece went away, or what the really optimal way was to vent the
> cold gas released during a helium fill. The two stacks on the mid field
> magnets behave very differently--the one with the fill port and the helium
> sensor appeared to be wide open to exiting helium, whereas the other stack
> was extensively set up with baffles or other internal structures which
> impeded the helium.
>
> I have a very strong preference for filling magnets that feature the cross
> piece, where how much helium is exiting through which stack is transparent
> to me.
>
> My questions are, has anyone modified their UltraShield with the Ascend
> style cross piece? Alternatively, does anyone know of reasons why that
> would be a bad idea?
>
> --
> Dave VanderVelde
>
>
-=-=-=-=-=-=-=-=-=-=-=-
Groups.io Links: You receive all messages sent to this group.
View/Reply Online (#3162): https://urldefense.com/v3/__https://ammrl.groups=
.io/g/main/message/3162__;!!PvDODwlR4mBZyAb0!TZSYvTb6d4XykdDmbx2_NHG_ZuqgoW=
s8_aQa473qwA7n6o2G61Vff99cb0HIkJBQWK-nysbSGTdehdqAhMVd6G96g18n$
Mute This Topic: https://urldefense.com/v3/__https://groups.io/mt/117496151=
/7559972__;!!PvDODwlR4mBZyAb0!TZSYvTb6d4XykdDmbx2_NHG_ZuqgoWs8_aQa473qwA7n6=
o2G61Vff99cb0HIkJBQWK-nysbSGTdehdqAhMVd6ArExOu9$
Group Owner: main+owner_at_ammrl.groups.io
-=-=-=-=-=-=-=-=-=-=-=-
(image/jpeg attachment: f9c3dd05-85a9-423d-a384-bd3bc230d684.jpg)