Author Topic: Cameca sample holders  (Read 159 times)

Probeman

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Cameca sample holders
« on: May 16, 2017, 10:48:13 am »
I learned something new today (probably obvious to everyone else!).

Our machine shop had machined some new slightly longer screws that hold the sample holder to the sample "cassette"? (that slides into the airlock "prongs"), because the old shorter screws were starting to strip out the threads in the insulating pieces. This is for the 2 + 2 sample holder for 2 thin sections and 2 round mounts for standards.

So I dutifully checked the conductivity between the sample holder and "cassette" in case the longer screws were shorting out the insulator and sure enough there was a short. 

So I backed out the screws to attempt to determine how much shorter the new screws needed to be and to my surprise there was still a short. So I checked more closely and discovered that although the sample holder looks symmetrical, it apparently can be mounted in either orientation. And in fact in one orientation the sample holder does not short, while in the other orientation the sample holder *does* short out to the "cassette".

So that might explain the odd sample current readings that we occasionally obtained!   Anyway, now the sample holder has some arrows drawn on it to show the proper mounting orientation.
john
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Owen Neill

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Re: Cameca sample holders
« Reply #1 on: June 30, 2017, 12:44:40 pm »
Related question - are SX50 and SX100 sample holders interchangeable?