(Click on Pictures to Enlarge)

  • 1 - 1/4" - 20 tpi Bolt, 6" long
  • 1 - Spring ~ 4".  Medium Firmness.  I was not able find one long enough with the right
    firmness, so I ended up using 2 springs as seen in the picture.
  • 2 - Nylon Spacers - 1/4" to 1/2" long.  I bought one 1" spacer and cut it in half.
  • 1 - 1/4"  hex or wing nut

    The LX200 Classics were shipped new with the mirror in the full aft position and held in
    place with a short 1/4"-20 bolt.  A small plastic plug was provided to cap the hole when
    the shipping bolt was removed.

    Simply remove the plug, and gently slide the bolt assembly inside and screw in place.  
    CAUTION: Do not over tighten this bolt, as it screws into the base of the primary mirror.  
    Just "snug" is fine. Make sure you have the hex nut in the full aft position on the bolt as
    not to put any pressure on the mirror at this time.

    Next, you simply focus the scope. Then screw the hex nut forward, placing rearward
    pressure on the bolt helping to keep the mirror stable. I then do my critical focus with the
    Feather Touch focuser. TIP: It would not be advisable to leave the bolt in while
    transporting or storing the scope. I have no concerns leaving tension on the bolt when
    making small focus changes. However, I would not suggest leaving too much
    compression on the springs if you have to make large course focus changes.  Again, It
    could place too much pressure on the mirror.  Just loosen the tension, change focus,
    then re-tighten the nut.

    Here's another interesting tip I picked up from others. The amount of mirror flop can vary
    from scope to scope.  Mirror flop can be increased if the grease around the primary is
    not distributed evenly.  To help redistribute, simply move the focus full forward and aft a
    few times.  This will help evenly spread the grease and cut down on "flop".
[Equipment Page]
Amateur Astronomy
LX200 Mirror Stabilizer
A simply aid to help with my LX200's mirror flop.  Mirror flop may not be as critical for visual observing, but as I learn more about CCD imaging,
the more it has become an issue. The bolt is a low cost, high value item.

To help alleviate mirror flop, some SCT's have a mirror lock built in. Unfortunately, the LX200 Classic's were not designed with one.  So,
through suggestions from others, I made a stabilizer bolt from common hardware.  The cost for all components was approximately $2 - $3 from
Ace H/W. You can also purchase one from various vendors for a fairly low price.

This type of stabilizer is an aid for controlling mirror flop, not a 100% cure for it.
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