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Damage if mirror locks left engaged

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#1 Momerath

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Posted 19 May 2013 - 03:53 PM

I accidentally left my mirror locks engaged the other night when attempting to focus after removing my reducer. Will this cause any damage to the scope? I moved the focuser several turns before I realized my error

thanks

#2 rmollise

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Posted 19 May 2013 - 04:07 PM

Probably not. Does everything seem OK?

#3 mayidunk

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Posted 19 May 2013 - 04:15 PM

I was once told that doing that accidentally for a short amount of time wouldn't likely be an issue. However, doing it all the time will definitely cause damage.

I've heard where some seem to think that partially engaging the mirror lock will reduce or eliminate mirror flop. While that may be true in some cases, in no case would I ever do that!

Listen to "Unca" Rod. If anyone knows, he does!

#4 Momerath

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Posted 19 May 2013 - 07:57 PM

Ok I was worried there for a min. Also should I be locking the mirror when I put the scope in its case?

#5 David Pavlich

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Posted 19 May 2013 - 08:51 PM

I don't know about Celestron, but if enough force is applied, it can bend the rod that connects the mirror to the focusing mechanism in a Pre-ACF/R Meade.

David

#6 mayidunk

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Posted 19 May 2013 - 09:01 PM

Ok I was worried there for a min. Also should I be locking the mirror when I put the scope in its case?

I would just leave it unlocked unless I was actually viewing with the scope, since transporting the scope with the lock on could damage it. Even if you're just wheeling it in and out of your garage, why take a chance? Just a thought...

#7 cavefrog

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Posted 20 May 2013 - 12:02 AM

uh, not sure... but the old EMC classics have a hole by the focuser knob for the SHIPPING BOLT that locks the mirror in place for shipping. one runs the mirror all the way to the back and then places the bolt through the hole to lock the mirror for shipping. as far as the clutch knobs are concerned, they should be left UNLOCKED for shipping. at least this is what the manuals state. I also know that a C-14 has lockbolts on the back that are for locking the mirror in place for shipping. I would think all the GPS models would work the same insofar as the mirror lock to be used to prevent mirror flop while in use, but I would also think to transport in the same fashion as the others I would run the mirror all the way to the back and use the mirror lock for transport.

Theo

#8 HowardK

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Posted 20 May 2013 - 07:29 AM

Rod...

I know u have a new 8" Edge....and i know u are a master with sct's...

Can u pls tell me if when collimating your new baby u find that collimation differs slightly from one side of focus to the other?

Mine does....maybe i will try next time out with the going to focus with a ccw turn of the focuser to avoid mirror flop....any thoughts?

#9 rmollise

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Posted 20 May 2013 - 08:06 AM

Rod...

I know u have a new 8" Edge....and i know u are a master with sct's...

Can u pls tell me if when collimating your new baby u find that collimation differs slightly from one side of focus to the other?

Mine does....maybe i will try next time out with the going to focus with a ccw turn of the focuser to avoid mirror flop....any thoughts?


No it doesn't. One thing to check is your setup on the rear port, the diagonal, etc. See what you see with the eyepiece plugged straight into the visual back.

BUT...The likeliest culprit, as Ed M. told you is a small amount of mirror shift. Did you do as he suggested and finish focus "uphill"?

#10 HowardK

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Posted 20 May 2013 - 08:37 AM

Thanks...quick reply

Not done the finishing uphill thing yet to be fair
Will also remove diagonal....well Denkmeier power switch diagonal ( willam optics) with Baader mk v binoviewers

Will next time out

#11 TG

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Posted 20 May 2013 - 04:27 PM

I accidentally left my mirror locks engaged the other night when attempting to focus after removing my reducer. Will this cause any damage to the scope? I moved the focuser several turns before I realized my error

thanks


Since you apparently have a C11HD from your signature line, no, it won't cause any damage as the mirrors are locked through flexible rods. You will notice much worse mirror shift though and that's an indication that the locks are active.

Tanveer

#12 Momerath

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Posted 21 May 2013 - 01:31 AM

Thanks. I wish there was a really good picture of the inside of the edge hd. The drawing does not provide enough detail

#13 EFT

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Posted 21 May 2013 - 10:16 AM

Thanks. I wish there was a really good picture of the inside of the edge hd. The drawing does not provide enough detail


What exactly are you looking for?

#14 TG

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Posted 21 May 2013 - 12:18 PM

Since you apparently have a C11HD from your signature line, no, it won't cause any damage as the mirrors are locked through flexible rods. You will notice much worse mirror shift though and that's an indication that the locks are active.

Tanveer


I distinctly remember reading the "flexible rods" bit. But the Edge HD whitepaper says "stainless steel rods". However, they're not threaded in but clutched so it's very unlikely there will be any damage.

Tanveer.

#15 EFT

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Posted 21 May 2013 - 12:23 PM

I distinctly remember reading the "flexible rods" bit. But the Edge HD whitepaper says "stainless steel rods". However, they're not threaded in but clutched so it's very unlikely there will be any damage.

Tanveer.


The rods are at least somewhat flexible. As long as you don't try to crank the focus all the way to the other end without releasing the clutches, there is unlikely to be damage.

#16 JoeR

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Posted 21 May 2013 - 01:28 PM

I've done it several times and still working just fine.

#17 orion61

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Posted 23 May 2013 - 02:59 PM

Rod...

I know u have a new 8" Edge....and i know u are a master with sct's...

Can u pls tell me if when collimating your new baby u find that collimation differs slightly from one side of focus to the other?

Mine does....maybe i will try next time out with the going to focus with a ccw turn of the focuser to avoid mirror flop....any thoughts?

Ihad a scope with the secondary slightly off center. Perfect collimation one side but off the other.
If the corrector has been off loot to make sure you arent missing a spacer shim.

#18 HowardK

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Posted 23 May 2013 - 06:13 PM

Its ok now
Fresnal pattern pretty equal thru focus
Important to finish focusing with CCW turn and to back off the mirror locks when testing collimation






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