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The Giant Binocular
- Thread starter savarin
- Start date
- Joined
- Aug 22, 2012
- Messages
- 4,271
Wow, 5 months gone by. I have been busy, honest.
I've been working on the mirror cells, most mirrors are collimated via 3 screws and these are no different but two mirrors means 6 assemblies.
This is all the bits, M6 screw passing through a brass bush that is an interference fit in the aluminium plate, two brass washers that the spring sits into so it doesnt wobble or cant, another brass bush threaded M6. The universal joint fitted to the top of the screw is so it can be extended to reachable distance whilst looking through the eyepieces.
All the bits together
Screwed into the bottom plate and mirror support plate, as can be seen as the screw is rotated it squeezes the plates together at that point thus tilting the mirror.
I will use a nyloc nut on the end of the thread so it cannot inadvertently unscrewed.
The full plate with the three collimation screws in place,
Now I depart from conventional methods, the bottom plate above is fixed to two linear rails that are fixed to the base of that tube.
This will allow 20mm of linear movement to each mirror at 90 degrees from each other.
I do not know if this will work but I'm hoping that if the images to each eye do not align perfectly I can tweak each mirror to bring them into co-collimation.
The brain can do this for small miss allignments but over a short period of time it can cause blinding headaches.
I've been working on the mirror cells, most mirrors are collimated via 3 screws and these are no different but two mirrors means 6 assemblies.
This is all the bits, M6 screw passing through a brass bush that is an interference fit in the aluminium plate, two brass washers that the spring sits into so it doesnt wobble or cant, another brass bush threaded M6. The universal joint fitted to the top of the screw is so it can be extended to reachable distance whilst looking through the eyepieces.
All the bits together
Screwed into the bottom plate and mirror support plate, as can be seen as the screw is rotated it squeezes the plates together at that point thus tilting the mirror.
I will use a nyloc nut on the end of the thread so it cannot inadvertently unscrewed.
The full plate with the three collimation screws in place,
Now I depart from conventional methods, the bottom plate above is fixed to two linear rails that are fixed to the base of that tube.
This will allow 20mm of linear movement to each mirror at 90 degrees from each other.
I do not know if this will work but I'm hoping that if the images to each eye do not align perfectly I can tweak each mirror to bring them into co-collimation.
The brain can do this for small miss allignments but over a short period of time it can cause blinding headaches.
- Joined
- Jan 21, 2013
- Messages
- 922
I'll settle for some racy telephoto images thru windows. I mean what else do you use giant binoculars for?thats going to be a very long wait guys, I'm not into astro photography
- Joined
- Dec 6, 2015
- Messages
- 829
They may change once you have it finished. Looking good (no pun intended)!thats going to be a very long wait guys, I'm not into astro photography
Sent from my SM-T500 using Tapatalk
- Joined
- Aug 22, 2012
- Messages
- 4,271
Made two sets of these ugly bits of 5mm aluminium plate to make two right angled drives to slide the mirror cell back and forth. 20 mm total.
travel.
They bolt together with a radio control car differential inside
The shafts are connected together with universal joints and will be operated from the top whilst looking through the eyepieces.
The brass part is bolted to the sliding component with the mirror and its cell on top, its the middle plate of the three in the pics in message 253.
The units are bolted to the back plate that holds the base of the hexagonal tubes apart.
I purchased the U/J's as they are cheaper than I can make them and I need a lot.
I'm still considering how I will join the control rods at the two halves (not shown) as I dont want the top half rods hanging down they will have to be spring loaded to retract out of the way but be easy to rejoin without any parts that can be dropped and lost in the dark.
The bottom rods can be a tight fit in the bearings but the top rods will have to be an easy sliding fit in the bearings.
travel.
They bolt together with a radio control car differential inside
The shafts are connected together with universal joints and will be operated from the top whilst looking through the eyepieces.
The brass part is bolted to the sliding component with the mirror and its cell on top, its the middle plate of the three in the pics in message 253.
The units are bolted to the back plate that holds the base of the hexagonal tubes apart.
I purchased the U/J's as they are cheaper than I can make them and I need a lot.
I'm still considering how I will join the control rods at the two halves (not shown) as I dont want the top half rods hanging down they will have to be spring loaded to retract out of the way but be easy to rejoin without any parts that can be dropped and lost in the dark.
The bottom rods can be a tight fit in the bearings but the top rods will have to be an easy sliding fit in the bearings.
- Joined
- Nov 25, 2015
- Messages
- 9,733
well that doesn't mean he isn't looking into space, he just isn't photographing it.
- Joined
- Aug 22, 2012
- Messages
- 4,271
The control rods need some form of bracket with a bearing so I knocked up there 2 from some aluminium angle
They worked but I wasnt satisfied so thought maybe just use the angle bolted to the vertical back plates.
If I include the control rods for the colimation screws for each mirror thats a total of 36 brackets and bearings.
Thats too many ugly brackets. I have some lumps of 12mm plate left over so maybe I can cut some neater looking brackets from that.
So after marking them out I cut them free to machine them.
To allow me to turn them on the lathe I had to make some packing plates (at least they may come in handy later)
The first one came out fine but what a palaver
The thought of making 35 more of these was very daunting and time consuming.
Then the brain storm that I wish had occurred earlier happened.
How about using these
![control rods 4].jpg](https://www.hobby-machinist.com/data/attachments/370/370454-a73424c2a28a6bc19f98e1db1cf4c751.jpg "control rods 4].jpg")
Average price in Oz $7 - $25 each, I dont think so, off to ebay and china at $2.20 each.
Thats more like it but 4-6 weeks for delivery.
Still that gives me time to finish the other side gear box and mounting.
They worked but I wasnt satisfied so thought maybe just use the angle bolted to the vertical back plates.
If I include the control rods for the colimation screws for each mirror thats a total of 36 brackets and bearings.
Thats too many ugly brackets. I have some lumps of 12mm plate left over so maybe I can cut some neater looking brackets from that.
So after marking them out I cut them free to machine them.
To allow me to turn them on the lathe I had to make some packing plates (at least they may come in handy later)
The first one came out fine but what a palaver
The thought of making 35 more of these was very daunting and time consuming.
Then the brain storm that I wish had occurred earlier happened.
How about using these
Average price in Oz $7 - $25 each, I dont think so, off to ebay and china at $2.20 each.
Thats more like it but 4-6 weeks for delivery.
Still that gives me time to finish the other side gear box and mounting.
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