ETX80 to dovetail conversion?

[Demonperformer]

Let me start with a confession. As a DIYer I am a great theoretician! Hence my need for advice and help.

OK, here's the problem. I own a Meade ETX80. No, that's not the problem, I think it is a great little scope [it can get down to mag 11 in my front garden with street lights all around - what could it do from a dark site? - I digress], but the mount, which would never have won 'product of the year award' even when new, is not. In particular the az drive has become digital and moves in about half-degree jumps, each one followed by those lovely little telescope-wobbles that we all know and love so well. Admittedly, when it settles down it is pointing at the object it was pointing at previously, but that isn't really the point [if you'll excuse the pun:)].

I have recently purchased a Nexstar 6SE, with that nicely designed 'dovetail' mount [and an accuracy that still leaves me breathless] which enables one telescope to be removed and another one attached to it.

I'm sure many of you can see where I am going with this.

My thought is that if I can somehow attach the nice ETX80 OTA to the nice dovetail mount I would be in short-refractor heaven. OK, I know that if I was to compare my etx with a REALLY good short focus refractor I would probably think mine had come from the argos catalogue reject department, but I like it because I know no better:).

OK, becoming a little more serious. As I see it the challenge boils down to:

1. Remove etx from mount [how? - for some reason the instructions that came with the scope missed this fairly elementary bit out!]

2. Purchase [where?] a bit of the strip-thingy [i think that's what it is called] that attaches to the telescope and slides inside the bit-that-holds-the-strip-thingy on the mount OR find some suitable alternative [what? where?]. The tube length of the etx is slightly longer than my 6SE, so presumably a replacement bit for the 6SE would be suitable [but probably not particularly cheap]. Maybe there is an astronomical version of B&Q somewhere that you just go and ask for a 30cm length of strip thingy and they slice a piece off? I really have no idea.

3. Attach [how?] the aforementioned piece of strip thingy to the etx. Maybe a set of mounting rings for a 80mm telescope would be a way?

Anyway - voila - Robert would now be my father's brother - I would now have two fully interchangeable excellent telescopes on an excellent mount.

The only questions are the hows, wheres and whats I have interjected in the above. If any of you have attempted anything resembling this before, your advice would be invaluable. Anyone else who has any ideas that could turn this great theory into great practice, I would love to receive your input as well. It may be that I am being totally impractical and the whole thing is a pipedream, but on the principle of 'if you don't ask you don't get' I'm asking.

Thank you all for wading through my post and for any help you can give.

[greenkat]

Hi there

I started off with an ETX70, but after buying a Skywatcher scope and a Heq5pro mount, I had exactly the same thought. Can I stick this little scope on this much better mount? .

Well, yep, I did

A quick and basic guid of what I did :

The ETX tube can be removed by opening the bottom of the mount and unscrewing one of the fork arms, then undo the altitude tightner and it should come apart. I'm sure there is a video on youtube that shows how to disasemble the ETX. If you intend using the mount again, watch for the spring in the fork arm and remember how to re-assemble it.

Then all I did was use black electrical insualtion tape and tape the tube nice and tight to a Skywatcher dovetail bar. Easy peasy, lemon squeezy

I did the same with my ETX90, but that has bolt holes in the bottom, so I had another dovetail bar drilled to fit.

Both ETX mounts are now redundant and I use the ETX70 as a guide scope (still learning guiding tho)

Good luck

Heres an online guide to taking the ETX70 apart

Disassembly of the Meade ETX-70

Greenkat

[Merlin66]

What's the outside diameter of the telescope tube?

Once you have it of the mounting, the easiest ( and probably cheapest - other than Gaffa tape!) is to buy a Vixen Dovetail bar, length to suit the tube and a couple of SkyWatcher tube rings. Bolt these together and clamp the tube in place. This dovetail will fit the other mount. Job done.

Dovetail bars

Tube Rings

[Demonperformer]

Thanks, thanks, thanks, guys ... exactly what I wanted.

Will definitely get the bits first, and make sure I have some means of mounting the scope before destroying - um, I mean dismantling - the etx mount. Don't really see any likelihood of ever using it for anything else.

Hadn't thought about using it as a guidescope ... maybe a bit big for my 6SE. Then again, I suppose I could find some way of attaching a mouning plate to the other side of the scope and then sliding the etx dovetail into that. Not sure the mount would cope though.

Thanks again and I will report progress when it happens.