Chriske

1 hour ago, Gina said:

Maybe just grease would work better that sealant.  Or perhaps a greased paper gasket - works for engines.

indeed...

No it does not at all, it is all to far away to see objects in 3D.
As a matter of fact most people do not know at all what advantages a bino-scope has over a 'single-scope'.
To be clear all mentioned here below does not count for binoviewers at all. A binoviewer-unit on a single scope is a completely different story. The only advantage that a binoviewer has in common with a bino-scope is that observing is done very relaxed because of that opened second eye. One disadvantage of a binoviewer is a little loss in magnitude.

- First of all there is a significant gain in magnitude when observing with both eyes open using a bino-scope. That has all to do with the brain. Physiologically the brain is not 'built' to observe with one eye closed. When we do observe with one eye closed, immediately the brain starts producing kind of a background' noise' to compensate for that 'lost' eye. Resulting in magnitude and colour loss.
You can all test this for yourself. Mount a regular pair of binoculars on a tripod. Just the same as you would do with a telescope. Do observe during daytime, say landscape. To begin with, close one eye and observe during two or three minutes one eye closed. Do protect that closed eye from light falling sideways into your eye, otherwise this experiment will not work. After a few minutes open that closed eye again and see what happens...
- Second : gain in colour
- Images are much sharper. That has to do because the brain likes to 'overlap' these two separate images. You can compare it with 'stacking' in a digital darkroom.
- relaxed observing. There's no need to get all your face strained up to have that one eye closed. That's why many observers do use an eye-cap btw.
- There is in fact a 3D-ish effect during observing. But that has nothing to do with real 3D. That 3D as many people noticed during observing through one of my Newt-binoculars has all to do with the fact that observing is done with 2 scopes thus 2 air-canals. While observing the air is always in motion, be it slow or fast. So the distortion of the images is not 'synchronised' in the two scopes. Depending one the direction of the motion of the air the eye receives the images a split-second out of phase. Resulting in a very pleasing way of 3D-ish observing. Needles to say it is not ok when there's to much turbulence. That 3D-ish effect, how I call it, is in fact nothing like 3D, but that is the best way I can describe it. You have to see it to understand. When people do observe and notice it, they all ask very surprised : Hey what did I just see..!. It's not always there.
This '3D-ish effect' is only visible while observing (especially) the Moon and planets. While observing Nebulae that effect is overshadowed by that gain in magnitude.

This is the fifth binoscope I'm busy building. This Kutter-bino is the first non-Newt.
Optics for my next(6th) Bino-Scope is almost polished out. The FL of hese two mirrors differ only 3(!)mm. That next one will be a 20" f/5.6 Newt.   It will be a superlight open truss. And there's a 3D-printer involved...!
Both focal length of two scopes to build a binoscope my differ no more than 5% of their FL, The brain can not handle bigger differences. That is in fact the hardest part while polishing. But to do that I use just one pitch for both primary mirrors. Regularly switching mirrors on that pitch is the key.
For this Kutter-Bino I'm building this very moment the FL of both mirrors need to be 100% the same. But that is very easy in this particular case because I grind/polish just one large set of blanks and will core both primary mirrors out of that larger one.
Collimating a binoscope, the first time it's a disaster, but after a while, like so many things, you get used to it. But in this case there are 8(eight!) mirrors to collimate, and it all has to arrive 'lined up' in that brain... fingers crossed..!!

Wish me luck..

The curved parts of that template were printed very thin, only one layer. Care had to be taken not to break that perimeter.

Meanwhile printing and has started.
Busy printing the template for that strange looking oblong hole in the secondary tube. When done I only have to lay it at the correct spot on the tube and draw were I have to cut and grind away.
I need to print it in two pieces because my printsurface isn't long enough.
That oblong hole is almost 20" long. 455mm to be exact.

After a few attempts we succeeded to have these three sevseg units working properly. Was not easy to find the correct settings.
Turning the potentiometer knob, I can adjust the IPD from 55mm to 78mm. That is, not the IPD itself yet, just the readings from the LEDdisplay of course.
I even can adjust the brightness of the display. Very handy.

Btw : High pressure in printed part is no problem at all. Care should be taken how the slicer is set, otherwise the part will crack.
Just made a water-rocket-launching-platform for my neighbours son. He took it with him on a camping trip last week and had lots of fun with it. I tested it until the printed part eventually cracked. That was when I got as high as 12-bar. That crucial printed part is the specially made conversion from Gardena-male to 1.5 litre Coke bottles.
We got as high as 35meter at 10bar btw, and at the same time were all soaking wet...
Next time I will make a 2-stage water-rocket, and we're aiming at 100meter...

Next step is to add a(3) SevSeg-display to that IPD unit. I could use a simple ruler to indicate how far the two eyepieces are separated but I chose not to and go for a electronic version. And it looks cool imo.
Yesterday we tried to  upload firmware to a Nano to drive these 3 displays. All we got was some weird looking 'figures' on the SSD-units(while turning the potentiometer - it's a 10rev pot btw)).
Think we made some wrong wirings between that Nano and the 3 SSD-units. I want to install 3 SSD-displays separated by a dot.

IPD-adjusting-unit done.
the bleu(transparant) part is a fixed part. Turning the red knob the light brown parts(together with the focusers) move in opposite directions.

This is what I got so far.
Still to design is the IPD adjusting unit before I'll start printing.

I want to install a dual-speed focusing unit, so a new setup is required here.
This is what I got so far.
in this new version there's a timing belt involved. Left is done right one still to draw.

My pal Marc decided to make himself a Gregorian telescope(instead of a Kutter)
That Greg will be 250mm f/24. Also planetary observing only.

A few days ago my single Kutter-telescope I drew was almost ready to start printed . And at the same time I was left with an extra set of 120mm Kutter optics. (I was making 2 sets of Kutter-optics simultaneously)
So I started thinking about that extra set of optics and what better solution than make myself a Kutter-bino...
With a focal length of 3720mm it will be challenge, I know. But I made a few big Newt-bino's in the past, so why not....

This is what I have so far. A lot of parts I already drew for that single-version can be reused. Lucky me...

Just ordered a small diagonal mirror for my Kutter. (Orion Optics UK) cost 70£
After ordering and paying(paypall) I now need to pay an extra 10£ before they send that mirror.
Is this a normal way off working..?

And what is 'Sales Carriage'..?

Added a cover to hide the electronics
- Contact-points power-packs
- Fan
-7815
-DC -DC converter

Do not forget to order M2 bolts/screws...

These units don't look very professional, I know. But when 'tuned' there's as good as any expensive dual speed focuser.
I've don this dozens of times.

When it arrive ,see how it performs. It probably will run very difficult(due to the thick grease inside).
If so, let me know, and I'll post some additional pictures how to proceed to make these work with 'butterly smoothness'.

You do have a lathe, so it should be 'piece of cake' to integrate that BD601 reduction in your system.
There's one decision you have to make, how to attach that device onto your scope. I'd go for drilling two tiny holes in the back of your scope and use M3 bolts. There's also the possibility of gluing that lower ring.

Hi me again, and  as promised a few pictures of a another Crayford I just assembled with a BD601 unit inside.
If not clear please ask...

Ok now I get it...
I'll disassemble my focuser tomorrow morning and post some pictures while reassembling it. It's almost bedtime here...
I can already say this :
The hole in the BD601 unit is 1/4" sadly enough(we're imperial) so in my case I need a very thin and small shim of copper to compensate for my 6 mm rod.
You'll need a ring to elevate the BD601 unit to overcome the height of that 13mm shaft. You must glue (or screw) that ring onto the the back of the scope. That ring should sit around that shaft.
I hope you're a handy man..?

I'm  afraid I do not understand what you're trying to say.

Feathertouch and a few other brands are ridiculously expensive.
That's the reason why we started making our own focusers with the feel of 'butterly smootness' as they like to call it.
Reminds me btw just a few years ago one open door in our observatory. A few weeks before open door a friend just bought himself a Feathertouch and came to visit our part of the OD. He started to smile when he saw our printed focusers (we were demonstrating) with that BD601 unit integrated. He took it in his hand and started focusing, just to feel if it worked smooth or not. Immediately his smile disappeared asking us : Why didn't I know you made these perfect focusers..? I paid about 250€ for that focuser. When I told hem we only spent a fraction of what he paid, he was not happy at all.

I do understand why people buy such expensive focusers. Most of us only buy(or build) one maybe two telescopes. But at the rate I build these scopes, my wife would not be happy if I would buy another Feathertouch or other expensive focuser again...

I always try to hide wires in project like this. It looks  better.
In this case I need to hide the wires of the laser(sitting in front of the eyepiece holder).
I need to make 'corridors' in the parts itself. For my laser there was no other way than to lead the wiring very close to the top of that part. After installing the laser I cover the corridor with a very narrow ring.

Mounted on my printed telescope.

This a drawing I made showing the completed unit from different angels. The bleu parts I do print these. Years ago when I did not had that 3D-printer yet we use to make them out of resin.
If you decide to use these BD601 units and you have printer, let me know, I'll send you the STL files.
The large knob is the 1:1 and the smaller one is the 6:1
Almost forgot, to fasten the large knob you need two M2 screws(they're not included)

Hey,

You beat me to it... These are the ones I was referring to.
The one I always use BD601 only cost a bit more indeed then the last time I bought them(years ago). That is if you buy them 5 at once (12$). Years ago they only cost 10$ a piece, I'm a bit surprised price got up that much.
They work very well BUT! You need to take them apart completely, take out the thick grease and reassemble them adding a bit of light lubricant. + release a bit of the pressure of the little lips that hold these units together.

The BD601 units are stamped versions, so not the same quality as the machined versions. But again modifying the BD series a bit and they work just as perfect I suppose. I always bought them by the dozen or so because we needed these for our telescope-making-course.
If you buy the BD601 let me know, I have some pictures how to take them apart and reassemble again. Reassembling is done with a bit of 'fingerspitzengefühl'. You should not press to hard on the assembly-lips to close the unit again. There are dozens and dozens in use in our telescopes at our observatory, they work just fine.

One more thing : If you need both speeds 1:1 and also 6:1 you should buy the BD601 unit.
The BD602 has ONLY the 6:1 reduction, there's no flange to attach the 1:1 knob.

Never tried the machined version myself, maybe they're far better. If you buy that one, please let me know, maybe I'll try that one also.

Good luck.
Chris

I use dual speed knobs in almost all my scopes.
I buy these units in US, costs about 10$.
And no there's no backlash at all in these units.
Need to look it up, forgot where I bought them.