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ES argon-purged pressure test?

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#1 Rigel_10

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Posted 02 March 2024 - 11:47 PM

The idea of argon-purged eyepieces is a fantastic design and offers protection from mode moisture, etc invading eyepieces but...
Is there anyway to test whether the seal is still holding or has failed someway? The design has been around a long time, are the eyepieces guaranteed to never lose their pressure seal?
Thanks

#2 Ernest_SPB

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Posted 03 March 2024 - 01:54 AM

Try to put the eyepiece into a fridge and check then how much moisture will be seen inside... :) 


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#3 beggarly

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Posted 03 March 2024 - 04:26 AM

Read this thread: https://www.cloudyni...inium/?hl=argon



#4 PKDfan

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Posted 03 March 2024 - 05:26 AM

I find it almost IMPOSSIBLE to believe that Argon would not eventually all leak out.
Eventually.


CS

#5 Rigel_10

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Posted 03 March 2024 - 09:43 AM

I find it almost IMPOSSIBLE to believe that Argon would not eventually all leak out.
Eventually.


CS


Agree, rubber O-rings do fail, just look what happened to the space shuttle.
Expansion and contractions happen, but how long before it takes place?

#6 Jon Isaacs

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Posted 03 March 2024 - 09:53 AM

Agree, rubber O-rings do fail, just look what happened to the space shuttle.
Expansion and contractions happen, but how long before it takes place?

 

The Space Shuttle failure was the choice of the wrong material, it failed catastrophically.

 

The loss of pressure in an eyepiece is the result of the Argon diffusing through the O-ring material. Argon is relatively large and diffuses relatively slowly which means very, very, very slowly.

 

I have one Explore Scientific argon purged and sealed eyepiece. I opened it up to add cross hairs... It's no longer filled with argon.

 

Jon


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#7 sevenofnine

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Posted 03 March 2024 - 06:45 PM

From the Explore Scientific website, their eyepieces are tested by submerging them down to 1 meter of water for 30 minutes. That's a pretty good final Q/C test IMO. You could test your eyepiece by doing the same borg.gif


Edited by sevenofnine, 03 March 2024 - 06:50 PM.

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#8 Ernest_SPB

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Posted 04 March 2024 - 02:04 AM

From the Explore Scientific website, their eyepieces are tested by submerging them down to 1 meter of water for 30 minutes. That's a pretty good final Q/C test IMO. You could test your eyepiece by doing the same borg.gif

In case of leakage they can reject an eyepiece with defect.

What are options for eyepiece owner after negative result of the test?



#9 archer1960

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Posted 04 March 2024 - 07:21 AM

In case of leakage they can reject an eyepiece with defect.

What are options for eyepiece owner after negative result of the test?

Take it apart, dry it out, reassemble it, and start using it...



#10 pregulla

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Posted 04 March 2024 - 07:34 AM

You may try cooling it in a fridge for a while, then placing into warm water. If there are leaks the expanding air will create bubbles.


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#11 Rigel_10

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Posted 04 March 2024 - 08:11 AM

I have seen ES (82 series) eyepiece sold without the argon gas treatment for a cheaper price. I'm guessing these EPs failed the test and were then sold as-is with no gas?
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#12 pregulla

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Posted 04 March 2024 - 08:40 AM

Maxvision have different nosepieces than ES versions. My guess they had a shortage of barrels/seals so they took some off their Bresser lines to make non argon purged versions. But who knows...


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