Jump to content


Photo

Polar scope problem


  • Please log in to reply
7 replies to this topic

#1 leshiggins

leshiggins

    Advanced Member

  • Members
  • PipPipPip
  • 32 posts

Posted 18 July 2008 - 12:19 PM

I've had numerous problems  :( with my LXD75 SN-8 that have taken me over a year to find, diagnose and solve. The last of them (I hope!) is the polar alignment scope. The collar that carries the graticule is loose (and has been since delivery). Before anyone asks why I didn't sort this out from the start, let me just say I had MUCH bigger fish to fry with this equipment  :) - I've only just got round to this one.

The point is, can anyone give me any advice on how to make my polar alignment scope useable? How can I work out at what orientation I should fix it?  ???

#2 provencial

provencial

    Advanced Member

  • Members
  • PipPipPip
  • 34 posts

Posted 18 July 2008 - 11:09 PM

If you do not recieve the answer to your problem in this forum, try the LXD75 Yahoo Group at the below URL...

http://tech.groups.y...LXD75telescopes

#3 DSOMAN

DSOMAN

    Advanced Member

  • Members
  • PipPipPip
  • 329 posts

Posted 19 July 2008 - 09:50 PM

Aligning the LXD75 polar scope can be a pain and takes patience. Try this link below. It will tell you everything you need to know.

Brent

http://www.weasner.c..._alignment.html

#4 leshiggins

leshiggins

    Advanced Member

  • Members
  • PipPipPip
  • 32 posts

Posted 22 July 2008 - 12:12 PM

Hi Brent,

I'm familiar with stuff you sent the link for. Am I missing something? It seems to deal with polar alignment. My problem is that my polar alignment scope needs "calibrating" (the only word I can think of).

Basically, it seems that Meade never tightened the screws that lock the reticule in place (I wish those were the ONLY screws they failed to tighten).

It seems to me that I need to get the reticule in the correct orientation BEFORE I can think about using the Polaris-Kocab method.

Les.

#5 DSOMAN

DSOMAN

    Advanced Member

  • Members
  • PipPipPip
  • 329 posts

Posted 22 July 2008 - 04:06 PM

Hi Les,

What I did on my LXD75 was to first align the long cross hair line with the counterweight bar. I then put Polaris on the center cross hair. Now, if you rotate the scope from one side to the other Polaris should stay centered on the cross hair. If you can see a terrestrial object that will work just as well.

If it strays from the cross hair as you rotate the scope then you need to adjust [very slightly] the three Allen screws.

Keep adjusting until you can keep Polaris centered, more or less - it does not need to be perfect,  on the cross hair as the scope is rotated from one extreme to the other.

This is the hard part as everything interacts.

Once you have this done you are ready to align the scope on Polaris using various methods.

Don't over tighten the Allen screws, they will strip!

Brent

#6 cannon

cannon

    Advanced Member

  • Members
  • PipPipPip
  • 208 posts
  • LocationFlorida

Posted 22 July 2008 - 04:50 PM

You can get 3 replacement screws from scopestuff.com. They are longer and have a knurled knob on them. Much easier  to work with instead of allen set screws.

#7 leshiggins

leshiggins

    Advanced Member

  • Members
  • PipPipPip
  • 32 posts

Posted 24 July 2008 - 12:34 AM

Hi guys!

Sorry, but I think the question you're answering is not the question I'm asking. If you take a look at the attached photo, you'll see clearly what my problem is - a loose reticule collar. The consequence is that the cross-hairs do not have a FIXED orientation with respect to ANYTHING.

I need two things:

1. How do I stop the collar flapping about?
2. How do I get the cross-hairs correctly aligned with the silver scale so that I can do all the tricksy polar alignment stuff?

Thanks.

#8 DSOMAN

DSOMAN

    Advanced Member

  • Members
  • PipPipPip
  • 329 posts

Posted 24 July 2008 - 10:02 AM

Les,

As they say "one picture worth thousand words"

The collar you are referring to is held tight by three very small slotted screws located on the collar toward the mount. The collar assy will unscrew from the mount if the screws are backed off.

You don't need to worry about the silver scale to align the polar scope. Just be sure the long cross hair line on the reticule is pointing toward and parallel with the counterweight shaft before tightening the three screws on the collar.


Brent




0 user(s) are reading this topic

0 members, 0 guests, 0 anonymous users