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Mounting a Coronado Telescope on a Meade LX 80

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#1 jkevn

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Posted 29 November 2012 - 08:44 PM

I recently purchased a Coronado SolarMax II telescope, 90 mm DIA., and LX 80 Mount (a complete package from Optics Planet). The dovetail interface part, used for attaching the telescope to the LX80 mount, is clearly not designed for use with this telescope and this mount. Meade was unhelpful in helping me resolve this issue. Their response was that, although it was designed for use on another telescope, I should be able to get it to work with this one.

I attached a photo. Notice how far forward the telescope needs to be to be balanced on the declination axis. It is only being held by two 1/4-20 screws on the dovetail slider.

I am planning on designing a new dovetail mount, and having it made by a machine shop. But I would rather buy one that works. Any comments, or suggestions would be greatly appreciated.

thanks,

Kevin

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#2 mayidunk

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Posted 29 November 2012 - 09:15 PM

Can you relocate the clamshell behind the lever?

#3 DaveJ

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Posted 29 November 2012 - 10:12 PM

Can you relocate the clamshell behind the lever?


That, or better yet, get proper-sized rings and mount the rings to a longer dovetail plate. That's definitely what I would do.

#4 ourobouros2k2

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Posted 29 November 2012 - 10:12 PM

Ironic that a coronado (meade) scope won't fit without modifcation on a meade mount.

#5 faltered

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Posted 30 November 2012 - 03:10 PM

Ironic that a coronado (meade) scope won't fit without modifcation on a meade mount.


That doesnt surprise me at all :) Not sure when Meade is going to figure it out....

#6 Griffin!

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Posted 30 November 2012 - 03:34 PM

I've seen a few LX80s with coronado scopes on them (and used them) and none had an issue with balancing.

Just based off your picture it looks like you have the dovetail attached incorrectly to the clamshell on the Coronado, it should be centered. I believe there are 2 holes on the coronado and 3 on the dovetail (assuming optics planet sent you the correct one), so you would attach it to the coronado using the 2 outside holes on the dovetail.

After that you would just need to adjust the scope inside the clamshell ring and if need be move it behind the tuner.

#7 mayidunk

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Posted 01 December 2012 - 03:53 AM

He probably has the dovetail mounted like that because that's where the scope's balance point is, hence the suggestions for tube rings, and moving the clamshell back on the OTA.

#8 jkevn

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Posted 01 December 2012 - 08:50 PM

Thanks for all your suggestions.

Every photo of this telescope on any mount I have ever seen shows the clamshell mounted in front of the etalon adjustment lever, never behind it. It is impossible to mount the clamshell in front of that lever and balance the tube without a huge offset of the dovetail, and then, only using two screws, as showed in that photo I posted.

Mounting the clamshell behind the lever allows proper blance using three screws on the clamshell instead of two. The dovetail is still an extremely *BLEEP* design, because the screws don't align with the flats on it, and some other reasons. I will probably design and machine a new dovetail.

Bob, thanks for the suggestion about moving the scope in the clamshell to the other side of the lever. That helped a lot.

The Meade manual for alignment for the Meade LX 80 mount is poorly written and confusing. Their phone/email help about the dovetail was totally unhelpful.

One important warning about something I discovered today about aligning the Meade LX 80 mount: in the altazimuth configuration, you have to put their combination level/compass in the diagonal eyepiece holder to align north magnetic direction and telescope tube leveling. If you happen to be holding the remote control in your hand anywhere near the compass while you are doing this, the controller has an electro-magnetic field that will deflect the compass north direction while you are positioning the tube, so your alignment will be very messed up. I took me a while to figure this out.

I was using the telescope in the daytime with a 2-star alignment (only relying on the approximate slewing to two stars, since I couldn't see the stars in the daytime, to set alignment). This eventually worked well for visual observing in the daytime. The sun would stay in view for a good 20 minutes without drifting out of the field of view.

Kevin

#9 exparrot

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Posted 02 December 2012 - 07:34 AM

I only use that little compass on the tripod, before I set the mount on it. That little circular cut-out in the center of the top plate of the tripod fits the compass nicely. I then position the tripod until it's pointing magnetic North. After putting the mount on, I remove the lock screws from the dovetail saddle and set a torpedo level on the top edge. After leveling it, I lock the altitude clutch and put the screws back in the saddle. Then, I mount the OTAs.

The little bubble in that compass/level device is so tiny I can barely see it, so I only use the compass.

Jerry






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