Jump to content


Photo

Lightbridge primary locking screws

  • Please log in to reply
14 replies to this topic

#1 B Brummell

B Brummell

    Lift Off

  • -----
  • Posts: 11
  • Joined: 04 Jun 2012

Posted 06 February 2013 - 05:07 PM

Hi All,

Just a thought, but does anyone see a problem with me keeping my primary locking screws locked down after bringing the scope indoors after a few hours of using it outside?
It's just more convenient. The next time I take the scope out, only minor adjustments are required for good collimation.
...am I going to do any damage to the mirror do you think?

Thanks!

#2 Astrojensen

Astrojensen

    Fly Me to the Moon

  • *****
  • Posts: 5458
  • Joined: 05 Oct 2008
  • Loc: Bornholm, Denmark

Posted 06 February 2013 - 05:46 PM

I've thrown mine away. They are a real pain in the behind, always messes up collimation when you've just got it right. I used the ones on my 12" once and then threw them away. It holds collimation just fine without them, as long as I keep the springs tight by tightening the collimation bolts all the way down and loosen them just enough to collimate the primary.

No harm will befall the mirror by keeping the locking screws in place and locked down.


Clear skies!
Thomas, Denmark

#3 mogur

mogur

    Apollo

  • *****
  • Posts: 1180
  • Joined: 29 Jul 2011
  • Loc: WI

Posted 06 February 2013 - 07:16 PM

I've got mine collimated very close with the adjuster knobs. Now when I use the scope I tweak it using only the locking knobs. This works because I keep the trusses connected during movement/storage.

#4 Carol L

Carol L

    Fly Me to the Moon

  • *****
  • Posts: 7288
  • Joined: 05 Jul 2004
  • Loc: Tomahawk, WI 45N//89W

Posted 06 February 2013 - 09:03 PM

I've thrown mine away. They are a real pain in the behind, always messes up collimation when you've just got it right. I used the ones on my 12" once and then threw them away. It holds collimation just fine without them, as long as I keep the springs tight by tightening the collimation bolts all the way down and loosen them just enough to collimate the primary.


I threw mine away too, and also have the springs on my 16" Lightbridge tightened all the way.
Works great. :)

#5 Project Galileo

Project Galileo

    Viking 1

  • *****
  • Posts: 843
  • Joined: 14 Nov 2007
  • Loc: Jefferson County, Colorado

Posted 06 February 2013 - 11:42 PM

Another throw away here. Beefy springs tightened all the way. Works like a dream.

#6 pdfermat

pdfermat

    Apollo

  • *****
  • Posts: 1075
  • Joined: 12 Nov 2007
  • Loc: Wisconsin

Posted 07 February 2013 - 12:01 AM

Yep, me too - locking screws are long gone. I replaced the original carpy springs with the beefiest I could find at Ace Hardware. After tightening the collimation bolts all the way down, collimation holds like a dream the entire night.

I never liked the idea of keeping the locking screws tightened after observing when I did use them, though. I always worried there would be some undue stress on the system that could lead to no good.

#7 Damo636

Damo636

    Ranger 4

  • -----
  • Posts: 326
  • Joined: 16 Aug 2011
  • Loc: Co Fermanagh, Northern Ireland

Posted 07 February 2013 - 04:11 AM

I have also removed the locking screws and upgraded the springs with the Bobs Knobs heavy duty replacements.

#8 John rombi

John rombi

    Viking 1

  • -----
  • Posts: 877
  • Joined: 14 Aug 2005
  • Loc: Sydney, Australia

Posted 07 February 2013 - 03:58 PM

Upgraded to stiffer springs and removed the locking pins.

#9 Don Taylor

Don Taylor

    Viking 1

  • -----
  • Posts: 695
  • Joined: 12 Jul 2009
  • Loc: South Kansas

Posted 07 February 2013 - 07:53 PM

I use the threaded holes for the lock knobs to mount my counterweights (I use an ST80 finder and big eyepieces).

Attending RMSS 2011 the vibration from. ~400 mile trip caused the Collimation screws to unscrew and the springs to fall out.

So, now I install the lock screws whenever transporting the scope.

#10 jgraham

jgraham

    Voyager 1

  • *****
  • Posts: 13905
  • Joined: 02 Dec 2004
  • Loc: Miami Valley Astronomical Society

Posted 07 February 2013 - 10:12 PM

No worries, leaving the lock screws set shouldn't be a problem at all. I leave mine set all the time. I just tweak things a bit when I set my scope up. Mine's all stock with the original springs. I just pulled 'm in a bit when I first set it up and left it that way. If it t'ain't broke I t'ain't gonna fix it. :)

#11 B Brummell

B Brummell

    Lift Off

  • -----
  • Posts: 11
  • Joined: 04 Jun 2012

Posted 08 February 2013 - 05:21 PM

Thanks everyone for putting my mind at rest.

This way I have no mirror slop at all and setting up is even faster.

Thanks again

#12 Gastrol

Gastrol

    Apollo

  • *****
  • Posts: 1358
  • Joined: 04 Nov 2011
  • Loc: los angeles

Posted 08 February 2013 - 06:28 PM

I didn't throw mine away. I've got them in my parts bin. I know, one day, I'll use them for something.

#13 Astrojensen

Astrojensen

    Fly Me to the Moon

  • *****
  • Posts: 5458
  • Joined: 05 Oct 2008
  • Loc: Bornholm, Denmark

Posted 09 February 2013 - 04:32 AM

I didn't throw mine away. I've got them in my parts bin. I know, one day, I'll use them for something.



I haven't literally thrown mine away, I was speaking figuratively. I have a large case with "useful items" as well (read: lots of junk that I almost never, ever need again!) :grin:

But the locking screws can be used as spare collimation screws, in case a knob breaks or it unscrews during travel and get lost or whatever.


Clear skies!
Thomas, Denmark

#14 Ed D

Ed D

    Gemini

  • *****
  • Posts: 3115
  • Joined: 30 Apr 2010
  • Loc: Sunny South Florida

Posted 09 February 2013 - 09:26 AM

I'm another one with the lock screws in the parts bin. Even snugging down the screws throws my collimation off in my 6" f/8. The collimation holds very well without them, even when transporting the scope in my car.

Snugging down the locking screws won't hurt the scope with normal temperature changes. But...

Ed D

#15 John rombi

John rombi

    Viking 1

  • -----
  • Posts: 877
  • Joined: 14 Aug 2005
  • Loc: Sydney, Australia

Posted 10 February 2013 - 03:41 PM

I use my locking pin as a on/off switch for my scope mounted laser.






Cloudy Nights LLC
Cloudy Nights Sponsor: Astronomics