2 replies to this topic

[fromEarth]

Hi --

 

I recently got Apertura 6" f/4 scope (below) and this is my first Newtonian system using tube rings. 

 

https://www.highpoin...tonian-ota-6f4n

 

Tube rings are attached to an 8.75" (~ 220mm) - long dovetail bar. I am thinking of adding another dovetail bar on the top of the tube ring, in order (1) to use it as a handle and (2) to move finder/guide scope to the dovetail.  Is this a recommended way of using an extra dovetail? 

 

BTW, I cannot find a right dovetail with a correct length (220mm) and hole positions - the distance between two holes on the tube ring top is 19mm.  

 

Is there anyone who tried the same mod with this GSO/Apertura/TPO scope? Please share your idea and advice. Thanks!

[james7ca]

I'm not sure why you are concerned about "the distance between two holes on the tube ring top is 19mm," but you generally only need one screw (the center one) to attach a Vixen-style dovetail to the rings. Also, while you may not be able to find an exact match in length you can certain find dovetails that are close to 220mm in length that have slots near to both ends instead of a single screw hole and those slots allow the dovetail to be mounted to different screw-hole spacings.

 

It seems like the following is a close fit, but you will have to measure the distance between the center screw holes on the tube rings:

 

  https://www.amazon.c...ics,231&sr=1-18

[Chad7531]

I would buy a solid replacement for the red bar you have and then use the red bar for your extra rail. I had one on my 6” f5 and replaced it because it flexes, ADM makes them way more solid. But you can do whatever you want with the extra holes in your rings, I put handles on mine for manual slewing. I have a free extra pair by the way if anyone wants them, send me a pm.

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Edited by Chad7531, 09 December 2022 - 10:43 AM.