Modifying a diagonal with an eyepiece focuser

[Paz]

I have a dual speed focuser and a filter wheel both of which I like using with my C8 and MC-127, but I can;t use them both at the same time because it moves the centre of gravity back quite a bit and adds up to quite a lot of weight, and it means I have to move the primary mirror further from its natural position which affects the effective focal length of the scopes which has an impact if I'm measuring things.

I have a Williams Optics RACI diagonal with a built in eyepiece focuser which is great as it means I can use a filter wheel and still have decent focus control without my dual speed focuser, but I'm gradually using that diagonal less and using a mirror diagonal more. However my mirror diagonal doesn't have this focusing feature. So I was wondering is is possible to modify my mirror diagonal to build in a focuser, for example I have found a Baader focusing eyepiece holder but (1) I can't remove the eyepiece holder side of the diagonal it seems and (2) if I could would the baader eyepiece focuser fit anyway. Here's a link to it...

https://www.rothervalleyoptics.co.uk/baader-125-helical-focusing-eyepiece-holder-t2.html

I can however remove the nosepiece side - is there any kind of small/light focusing contraption that could go on that end?

[DRT]

The Baader holder you linked to, and the slightly more expensive ClickLock version, have T2 female threads designed to fit diagonals and extension tubes with the male T2 thread, such as the Baader T2 Prism.

Have you considered opening up your two diagonals to see if the mirror would fit inside the casing of the RACI?

[Paz]

2 hours ago, DRT said:

The Baader holder you linked to, and the slightly more expensive ClickLock version, have T2 female threads designed to fit diagonals and extension tubes with the male T2 thread, such as the Baader T2 Prism.

Have you considered opening up your two diagonals to see if the mirror would fit inside the casing of the RACI?

Thanks, I'll have a look at Baader diagonals, purely for "research" purposes!

I don't think the mirror will fit in the raci diagonal. Here they are side by side.. mirror on the left, raci on the right (and check out the smaller field stop in the raci diagonal!)...

[DRT]

One thing I think is certain is that the EP holder on that mirror diagonal will come off. I have no idea whether or not the thread that fixes it to the diagonal will be the same as the prism but it will come off - it might just need some persuasion