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Sticky needle

Discussions about GC and other "gas phase" separation techniques.

6 posts Page 1 of 1
Hello,
We are having an issue with the Combi-Pal auto sampler attached to our G.C. After injecting the first sample the bottom of the lower needle guide does not drop back to the bottom of the needle, but "sticks" about 2cm up, which leaves exposed needle. This affects the Z value of the sample tray (the needle does not reach the sample vials or injector, resulting in "object not found" error). I would like to know if I can loosen the screws, or grease the metal arms to ensure the guide returns to the bottom of the needle.
Thanks,
Nat
NatRoy,

Not going to like my answer, but time for a PM by your friendly service rep. I do service for a living and I had my customer go directly to LEAP to service theirs since these puppies are quite sophisticated. Not that expensive, by the way, at least by what I have seen.

Best regards,

AICMM
I agree with AICMM and can add that the PM will include cleaning and lubing the parts you're talk about, as well as the belts inside the sampler.
The combi pal system has two bungy cords in it and some times these get a little worn (memory is increased)

This might be some part of your problem

Cheers

Matt
Clean the post with some methanol on a Solon Q-tip, or a paper towel if you can get the post out.
I agree with Matt.

Almost certainly the bungy cords.

There are two sets in the system that should be changed at least yearly.

You can order spare cords from CTC or a supplier and fitting is fairly straightforward.

Alternatively, have a PM done. They should be changed on a PM without fail.
Bruker (and Varian) Engineer happy to give advice on GC, GCMS and LCMS products.
6 posts Page 1 of 1

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