Since Frank mentioned cryotongs, I wanted to point to a video of their use
on youtube:
http://www.youtube.com/watch?v=ikiF2qpCRKs
Jim
On Wed, 8 Jun 2011, Frank von Delft wrote:
> Hi Zhijie --
>
> With all manipulations on the goniometer, I strongly advise what I learnt
> from Elspeth Garman: practice, practice, practice... but not with your real
> crystal! Take it down, put up a dummy pin, and take the time play around. I
> imagine even a non-hollow pin can be bent without throwing it off with
> sufficient practice -- though Weikai is right, with those pins it'll be
> REALLY tough, the special Hampton pins are much recommended, because they
> have a weak point, making them far easier to bend. A little tool is also
> supplied.
>
> I do not agree however that you need a beamline with Kappa -- indeed, if you
> were at such a beamline, there would be no need to bend the loop! (How often
> I've wished for it...) The un-bent loops fit perfectly well into cryotongs,
> as long as you affix them to the base at the right length; once bent, the
> pins may not fit anymore, but you can always straighten them again before
> retrieving them.
>
> Of course, if you've already harvested your crystal on a non-bendable pin,
> this doesn't help; but we routinely bend the loop itself, by pushing on the
> stem of the loop (close to where it attaches to the pin), with a pipette tip
> cut into a sharp point simply with scissors (you want something non-metal, so
> as not to conduct heat onto the sample.) It's not exact, of course, and
> (again) takes some practice. But very effective -- it's rescued umpteen
> datasets for us. But BEWARE: DO NOT BREATHE WHILE DOING THIS! (Go figure.)
>
> HTH
> phx
>
>
> On 07/06/2011 23:33, Li, Weikai wrote:
>> Hi Zhijie,
>>
>> This loop is good if you have a long unit cell on one dimension and you can
>> align your crystal in a particular direction. You basically need a
>> beamline equipped with Kappa, which allows you to directly put the crystal
>> on with the plastic tube. A normal cryotong does not hold the bent loop.
>>
>> Regards,
>>
>> Weikai
>>
>>
>> ________________________________________
>> From: CCP4 bulletin board [[log in to unmask]] On Behalf Of Zhijie Li
>> [[log in to unmask]]
>> Sent: Tuesday, June 07, 2011 5:30 PM
>> To: [log in to unmask]
>> Subject: [ccp4bb] Hampton's adjustable cryoloop
>>
>> Hello,
>>
>> I just noticed that Hampton Research carries this adjustable mounted
>> cryoloop (HR5-900):
>> http://hamptonresearch.com/product_detail.aspx?cid=24&sid=136&pid=385<wlmailhtml:{35C92305-260C-4820-B40D-05B0D91A0A8F}mid://00000065/!x-usc:http://hamptonresearch.com/product_detail.aspx?cid=24&sid=136&pid=385>
>>
>> This looks quite interesting to me, as it seems that not every synchrotron
>> station's configuration can allow the use of an extended arc.
>>
>> I wonder if somebody here can share some insights or experiences about this
>> adjustable cryoloop. I once tried to bend my non-hollow stainless steel pin
>> in liquid nitrogen with tweezers. It didn't work - the pin was too stiff
>> then I lost my crystal in the end. I wonder if this cryoloop was designed
>> such that bending it would be easier.
>>
>> Thanks in advance!
>>
>> Zhijie
>
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