Frankenbino Exposed II - Step by Step Instructions
I have to admit, there IS a short possible setup that you can buy and have no worries. That would be the Baader Prism (32mm) with the 1.25" Clicklock Clump EP holder and 1.25" Nosepiece threaded to a Powerswitch.
That setup already solved my reduced aperture problem and using 24mm eyepieces were producing three nice powers - x80, x130 and x220. Although x220 power is more suited for a planetary work rather than Deep Sky with 10" aperture.
But troubled by the idea mind, won't give a piece of it to a crafty hands.
First thing I noted, was the way that Filter Switch got mated with the Binoviewer (BV). It was done by this 2" Female Receptacle with two thumb screws as seen on the image and Dovetailed adapter that got threaded to the BV. (Not shown)
Next I disassemble the Baader prism to check if it's even possible to do, what I had in my mind. And what I had in my mind is to drill and tap 4 small holes into the alluminium body without hitting the prism it self.
After removing the prism I saw that it was possible.
Then I disassembled the 2" Female Receptacle from the Filter Switch, because that's what I was going to use for a fast and easy way of switching things over. Something similar to what Baader does with their Quick Exchanger.
It was connected by 4 small screws on it's backside.
Next I removed the rest of the adapters from the prism's body which are 2" Nosepiece and 1.25" Clicklock Clump and had marked 4 spots for drilling future holes according to a holes that were on the back of 2" Female Receptacle.
I had to be very precise. Due to a lack of spare parts I had only one shot to do it all.
Then, using the 1.6mm bit I carefully drilled four straight through holes. The idea was to use the 4 small screws to attach the receptacle to a prism housing.
For this project I bought 4 small M2x12 screws with Allen heads. But the original holes in the receptacle were too small to use them, so I had to widen them using 2mm bit.
Those four screws had to be flushed flat with the surface of the receptacle, because the dovetailed adapter would be sitting right on top of it. Therefor, I created deep enough recess for their heads, using 3.5mm bit.
After that I used M2 x 0.4 tap to make the threads for all four of the screws.
When I started to assemble everything back, I have encountered with a small problem. The locking ring of the 2" Nosepiece were protruding too high and wasn't letting the receptacle to lay down flat on the surface of the prism.
I didn't want to remove the locking ring completely, as it would be too risky of getting unscrewed when tightened in the focuser and all the weight of binoviewer and pair of eyepieces pulling it down.
Eventually I decided to remove the locking ring and file flat the threads of the nosepiece, just so that it would flush with the surface of the prism and allow the receptacle to lay down.
Then I attached the receptacle and tightened it with the screws. Now the receptacle would be laying exactly on the filed threads of the nosepiece and actually will act as a hard stop and won't let it getting unscrewed by the weight.
Now it was finally the time to assemble everything together. As you can see, it came out very nice and I maintain the shortest possible setup with Denk's binoviewer and Baader Prism.
Now I'm also able to use the pair of receptacle's thumbscrews to rotate binoviewers for a better viewing position
But that is not all!
If I wish to make it even shorter, I would simply remove the PowerSwitch and enjoy it even more. I would simply remove the dovetailed adapter from the bottom of PowerSwitch and thread it on to the BV it self, to get another, different magnification power.
But that is not all either!
If at any point I would decide to view the objects in mono mode using single eyepiece, it could be easily done.
I just remove the BV, take the original 1.25" Clicklock Nosepiece that came with the prism and thread it back to its place. Fortunately, the diameter of the Nosepiece were just matching the inner diameter of the receptacle, so I won't have to remove it each time i switching.
So after achieving everything that I wanted and more, it also nicely fits in the original case for storage and transportation.