Author Topic: GSO seconday holder rebuild ideas  (Read 228 times)

tingperbeachfnar

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Re: GSO seconday holder rebuild ideas
« Reply #15 on: January 31, 2018, 01:10:52 AM »
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I addressed the problem by using a rubber grommet on the screw as it would allow compression and spring back better, plus it was closer to the right shape for the holder recess. Nylon would likely work, but it wouldn't compress or conform to the shape of the angled screw head as well, and it would tend to permanently deform.
Red:

If you look at your secondary and the secondary holder in the photo, I believe they are somewhat different. As I understand it, the new GSO scopes are using secondary's that are bonded like the Synta/Orion scopes rather than captured like the Astrosystems secondaries except that they only use a single clip.

Am I right or wrong on this?

Jon

rennlispuring

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Re: GSO seconday holder rebuild ideas
« Reply #16 on: January 31, 2018, 12:10:26 PM »
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The most simple fix is cut two milk jug washer the size of the stalk and place on top of the stalk .

You can slit the washers so you don't have to remove the stalk.

I just use nylon screws ... They hold very well and have that nice compression feel to them.


David Patel

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Re: GSO seconday holder rebuild ideas
« Reply #17 on: February 03, 2018, 05:13:29 AM »
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All, thanks for the feedback
Jon, I want something that is actually spring loaded, meaning if I release a screw the holder should still keep contact with ALL 3 screws, without flopping.


The newer GSO (Zhumell in my case) secondaries do have a spring. Very smooth and easy to collimate.

Daniel Horton

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Re: GSO seconday holder rebuild ideas
« Reply #18 on: February 04, 2018, 11:52:02 AM »
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<p class="citation">Quote

I addressed the problem by using a rubber grommet on the screw as it would allow compression and spring back better, plus it was closer to the right shape for the holder recess. Nylon would likely work, but it wouldn't compress or conform to the shape of the angled screw head as well, and it would tend to permanently deform.
Red:

If you look at your secondary and the secondary holder in the photo, I believe they are somewhat different. As I understand it, the new GSO scopes are using secondary's that are bonded like the Synta/Orion scopes rather than captured like the Astrosystems secondaries except that they only use a single clip.

Am I right or wrong on this?

Jon[/quote]

Yes, I had noticed some difference in the photo related to the surround of the mirror. The mirror in the Z10 is bonded to the holder. I can't tell from the photo if there is an external housing that floats independently of the central shaft. Thespider'shub looks aboutthe same. If the whole system is fixed like the Z10 design, then one had better hope that the central screw head can wobble in the holder, otherwise it will be anything but "very smooth and easy to collimate", assuming one can even get the ******* screws to turn in the first place.

Even with the change I made it is easy to back out a twist or two and lose contact/adjustment on a screw. The central screw seems to substitute as the third leg of the tripod outside of some adjustment range.

Side note: One of the really irksome things about the Chinese made stuff is the lack of documentation or incorrect documentation.There are some really nice features that are not even mentioned or improperly explained. Zhumell's manual looks beautiful and simple...but is wrong in a number of important particulars. And they don't even bother to put a paper copy in the box, or a parts list, or even a page saying go to "www.... and download the manual." Focusing the finder scope is nothing like they describe and I ended up completely disassembling it to figure out how to get it to focus beyond 20 feet.