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Store dob tube vertically, mirror-bottom

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#26 WillR

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Posted 12 February 2025 - 09:52 PM

Thanks for the additional confirmations.

Just for fun: while reading other threads on this (where I also encountered Jon’s picture 😀), I ended up asking ChatGPT. Not sure on what it was trained, but the answer is surprising, which also pushed me to check here your practical experience…

[ChatGPT excerpt follows]
Storing a reflector telescope vertically with the mirror side down (resting on the primary mirror) is not recommended for several reasons:

Potential Issues:
1. Stress on the Primary Mirror: The weight of the entire optical tube assembly would put unnecessary pressure on the mirror, which can lead to stress fractures, deformation, or damage to the mirror’s surface over time.
2. Collimation Drift: The pressure on the mirror cell can affect the alignment of the optics (collimation), requiring more frequent adjustments.
3. Dust and Moisture Risk: If there’s any opening or gap, dust and moisture could settle around the mirror more easily when it’s facing downward, potentially causing corrosion or mold growth, especially in humid environments.
4. Risk of Damage: The mirror is often not designed to bear weight. Any accidental jolt or shift could crack the mirror or damage the support system.

Better Storage Options:
• Vertical Storage (Mirror Side Up): You can store it vertically with the mirror facing up as long as it’s securely supported. Use a dust cap to prevent debris from settling inside.
• Horizontal Storage: Ideally, store the telescope horizontally on padded supports. This distributes the weight evenly, reducing stress on the optics.
• Protective Coverings: Regardless of position, keep the telescope covered to protect against dust and moisture.

Would you like tips on how to create a safe storage setup for your telescope?

Okay, this is an object lesson in why ai is not ready for prime time. I don’t even understand this response. Better to ask the question here, as you have. 
 

If you store the telescope with the mirror at the bottom, the mirror is face up and there is no pressure on it. It is in a mirror cell, not in contact with the tube. There is no pressure on the mirror. 
 

Then there is this excerpt from your ai advisor:

 

“ Options:

• Vertical Storage (Mirror Side Up): You can store it vertically with the mirror facing up as long as it’s securely supported. Use a dust cap to prevent debris from settling inside.”

 

??? Mirror side up and mirror facing up are two different things. I have never heard of storing a telescope with the mirror on the top. This way lies madness.lol.gif

 

I store mine vertically in its base on a hand truck. If I am leaving it out, I don’t store it vertically, but angle it. I’m not sure why you can’t store it in its base if you have room to store both the base and tube separately. It has the same footprint in its base as the base alone and is only a few inches higher. Then you wouldn’t have to store the tube separately.


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#27 izar187

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Posted 13 February 2025 - 12:30 AM

Yes to storing newts horizontal, or at an angle.

I do too...  because I have the space to do it.

Store mine at ambient temp too, nowadays.

But I didn't have either option when starting out.

 

Couple of folks mentioned dust on the mirror.

The vast majority of that on my newts has come

from when they are open and used under night sky.

Spiders too, most often get in my scopes during use.

IMHO+E, based on none in my unused stored scopes.


Edited by izar187, 13 February 2025 - 01:43 AM.

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#28 grace

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Posted 13 February 2025 - 04:47 PM

I’m not sure why you can’t store it in its base if you have room to store both the base and tube separately. It has the same footprint in its base as the base alone and is only a few inches higher. Then you wouldn’t have to store the tube separately.

+1 on the comments about AI, it got me so confused laugh.gif

 

On your question: The rocker has a "much larger" base (relatively to a small apartment) - I have a good place to store the OTA vertically but the rocker base does not fit there. We have small children so the OTA must be secured, the rocker base seems less appealing to them lol.gif


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#29 WillR

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Posted 13 February 2025 - 07:42 PM

+1 on the comments about AI, it got me so confused laugh.gif

 

On your question: The rocker has a "much larger" base (relatively to a small apartment) - I have a good place to store the OTA vertically but the rocker base does not fit there. We have small children so the OTA must be secured, the rocker base seems less appealing to them lol.gif

Ok, I get it. The OTA will be fine vertically. Put a piece of foam under the mirror cell if you want to. Then just cover the top end with a cover if it came with one or even an oversized shower cap (Which I have on my 6”)


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#30 star acres

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Posted 14 February 2025 - 07:46 PM

If I ever have to store my telescope in a rough place, I'm smearing both mirrors with Vaseline and cleaning up the mess later. It's not in the rain, so I slap on the plastic cover and store it at any angle. I cap the focuser and all eyepieces are labeled in their original boxes.

#31 dnrmilspec

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Posted 14 February 2025 - 10:06 PM

If I ever have to store my telescope in a rough place, I'm smearing both mirrors with Vaseline and cleaning up the mess later. It's not in the rain, so I slap on the plastic cover and store it at any angle. I cap the focuser and all eyepieces are labeled in their original boxes.

Tell me that is a joke and you really didn't mean to suggest coating a telescope mirror with Vaseline.  

This is the beginner forum.  I want to be perfectly clear that at least one of us thinks that it would be an exceptionally bad thing to do, to rub any kind of petroleum product on a telescope mirror, under any circumstances. 


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#32 star acres

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Posted 14 February 2025 - 10:35 PM

Vaseline is childsplay compared to John Deere TY6341 polyurea grease. For that I detached the three screws. You finish off with 100% cotton and never use even the best paper towels on telescope mirrors or optics. I also coat heads and flying heads of VCR's with Vaseline for barn storage and such. That's a cleanup. You may have overlooked posts with age damaged telescope mirrors. This can be squashed. 



#33 izar187

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Posted 14 February 2025 - 11:41 PM

The original post read as how one orients the newt tube,

in an apartment, between uses. Not long term barn storage.  : )


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#34 Jon Isaacs

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Posted 14 February 2025 - 11:53 PM

Vaseline is childsplay compared to John Deere TY6341 polyurea grease. For that I detached the three screws. You finish off with 100% cotton and never use even the best paper towels on telescope mirrors or optics. I also coat heads and flying heads of VCR's with Vaseline for barn storage and such. That's a cleanup. You may have overlooked posts with age damaged telescope mirrors. This can be squashed. 

 

:scratchhead:

 

As was said, I hope this is a joke. There are simple ways to protect a mirror from deterioration due to aging. Storing the mirror in a dry, dust free environment goes a long way 

 

Cleaning the petroleum grease 100.000% will be difficult and may cause issues when recoating the mirror .

 

Jon



#35 WadeH237

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Posted 15 February 2025 - 08:02 AM

This is the beginner forum.  I want to be perfectly clear that at least one of us thinks that it would be an exceptionally bad thing to do, to rub any kind of petroleum product on a telescope mirror, under any circumstances. 

100% agreed.

 

However, if you are serious about wanting to protect a mirror for long term storage in a potentially hostile environment, there is a product called Photonics First Contact that is specifically made for coating and protecting optics.

 

It is a polymer solution that is applied as a liquid to cover the mirror.  It dries to a protective layer that can be later peeled off.  In addition to protecting the mirror, it leaves it in a pristine state when peeled off (it is used as much as a mirror cleaner as a protector).

 

It is both expensive and effective.  I probably wouldn't use if for a typical 8" Dob.  But if I were storing a premium telescope mirror for an extended period, I would certainly consider it.


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#36 dnrmilspec

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Posted 15 February 2025 - 10:05 AM

For the new person who drops by this thread with the same question.

 

Cleaning the mirror on your Newtonian telescope is a task you will only undertake infrequently.  A bit of dust on the mirror is not a problem at all.  I will not take a deep dive into that as there are  many excellent threads here on CN covering when to clean your mirror and how do do it.  It is something anyone who owns a telescope will have to consider at some time.   

 

Proper cleaning will not damage your mirror and a mirror will last many years and many cleanings without a problem.  The cost to re-coat an 8" mirror (for example) is not an expensive process, costing in the neighborhood of $100 or so at this point.

 

DO NOT PUT PETROLEUM PRODUCTS ON YOUR MIRRORS. AT ALL.

 

When we refer to "long term storage" we are not talking about a few months, between seasons.  If you are going to use long term "barn storage" on a telescope, I suggest you sell it and buy a new one when you are ready to start the hobby again. 

 

On Edit.

 

As Wade said though.  The product he mentioned, Photonics First Contact is excellent.


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#37 vtornado

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Posted 15 February 2025 - 11:48 AM

 The rocker has a "much larger" base (relatively to a small apartment) - I have a good place to store the OTA vertically but the rocker base does not fit there.

 

I have found that I do not have to attach my rocker to the lazy susan.  I put cloth friction tape on the bottom of the rocker box, and the top of the lazy susan.  The weight of the box and tube keeps it from sliding during use.  The larger lazy susan can be stored on edge to reduce the floor footprint.  It does result in an extra trip needed to bring out the base.

 

As for me, I store the tube horizontally if the tube comes in from the cold.  I have had condensation form on the secondary then drip onto the primary if stored vertically.  My bottom cover is cloth.   maybe I should upgrade to a plastic cover on the bottom???


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#38 Speedy1985

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Posted 15 February 2025 - 04:48 PM

I store mine uncovered in my non climate controlled garage and I keep it slightly tilted by about 15-20 degrees. I do that just in case there may be some moisture potential and also, at least in my mind, to deter and airborne dust buildup. 



#39 izar187

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Posted 15 February 2025 - 07:18 PM

if the tube comes in from the cold.  I have had condensation form on the secondary then drip onto the primary if stored vertically.

________________

 

Me too.  : )

This is how we learn.



#40 northernmike

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Posted 15 February 2025 - 10:42 PM

I know we are getting off the topic here , which was to store the tube vertically or horizontally , but I can't help myself commenting on the vaseline

''bad idea''....

I'm trying to imagine how many bags of cotton balls it would take , just to remove all the vaseline!!!lol.gif

Come on , be serious , vaseline on a parabolic mirror !!!shocked.gif



#41 WadeH237

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Posted 16 February 2025 - 05:02 AM

I know we are getting off the topic here , which was to store the tube vertically or horizontally , but I can't help myself commenting on the vaseline

''bad idea''....

I'm trying to imagine how many bags of cotton balls it would take , just to remove all the vaseline!!!lol.gif

Come on , be serious , vaseline on a parabolic mirror !!!shocked.gif

For all practical purposes, covering a mirror with a reactive substance, like petroleum jelly, would likely destroy the surface of the mirror.  And even if it didn't, the process of cleaning off the petroleum jelly certainly would.

 

I mentioned the First Contact product because it is the only way to safely apply a protective coating to a telescope mirror.  It is very good at what it does.  That said, it is not something that I would consider as a routine maintenance job.  If I were trying to restore a mirror that had been left exposed to the elements for years, or was filthy to the point of being literally non-reflective, then it might be something that I would try before having the mirror recoated.  As a protective product, if I were building my own Dobsonian over a long period of time, and was storing something like a large Zambuto mirror through a move to a different location, then I might use it.

 

As for storage, I keep my Dobsonians stored vertically with just the dust cover.  For my truss Dob, it's the same, but I store it with the secondary cage and truss poles removed.  I have kept multiple Dobs for multiple decades this way, and have never run into a problem.


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