DIY parallelogram binocular mount

[marcheenek]

Here is my recent small project - a p-mount for my Barska X-Trail 20x80 binoculars. I plan to build it out of some salvaged materials from my garage - aluminum and metal conduit poles, old wooden table legs, door hinges etc.

The dimensions:
Tripod height: 30"
Vertical pole height, including tripod: 55"
Long beam: 60" (36" binocular side + 24" counterweight side)
Short beam: 36"
So at the position presented in the picture, the binocular eyepieces are located at around 5.7'
The bino is 5 pounds, so I will need 7.5 pound counterweight.

The tricky part is to drill holes into aluminum poles - luckily a member from my astronomy club lent me a drill press, which should make the job easier.

I'm still not sure how to cut the holes in the exactly same plane on both ends of each pole. I would need some kind of jig for that. Any ideas?

Thanks!

[ZeroID]

Jig, yep, piece of cake.

The drill press has a drilling table with holes and slots. Get any piece of angle material, alum, steel or even make a up a wooden jig that can be bolted to the table and a stop fitted at some point, screwed glued whatever. Just press and hold the alum tube ito the corner of the jig and against the stop and you can turn them out all day.
Takes a wee bit of adjusting to begin with to get over centre and correct length. Use a Square and accurate micrometer\steel ruler and do a couple of test drills first to verify accuracy.
I use a 2" wide, 1" deep piece of aluminium channel withe a stud bolt which attaches it to the table and allows adjustment. Use the table slots and the table rotation to set it to the right position.
I'll do you a pic if you need of my system. The Serrurier owes it's existence to the jig and drill press. Best tool I ever bought, gets used constantly.

[marcheenek]

Please, a picture's worth a thousand words.

I drilled some 1/4" holes in 3/4" poles and see I have a problem with the drill bit going off-center for some reason - sliding off the curvature? Anyway to fix that?

Thanks for your comments

[ZeroID]

Ok, take some tonight or over the weekend and get them up for you. There are many ways you can do it.

[marcheenek]

Here's some update on the project. I made a tripod, azimuth bearing (Ebony Star laminate on teflon pads), and part of the bino bearing part.

[Poita]

I'd love to see some pics of your system.

[Dennis]

Hi Marcin

A great write up, plans and photos of your project – well done! Some nice woodwork – did you have the use of a Router?

Cheers

Dennis

[marcheenek]

Thanks for your kind words, Dennis. No, I don't have a router. I cut the circles out of plywood using a jigsaw and then used a belt sander to make the surface smooth.

[alistairsam]

Hi Marcin,

Nice work. how did you manage to drill the holes in the Al tubes ?
if you can, I'd recommend a router as well, even the non professional ones. Best $50 I spent. makes cutting circles so easy.

Brent, would be good to see pics of your jig

Cheers

[marcheenek]

For the tripod legs, I drilled holes through the wood firtst, then slid each tube into the wooden block and used it as a jig to drill the tube. It didn't come out perfectly but the final tripod is quite stable.

[marcheenek]

Some update on the project. Here is a jig I used - two metal pipe straps with washers holding the tube steady.
After drilling a hole on one side, I put a bolt through it and align it with a drill on the other side. It worked surprisingly well.
For tube connections I used washers made from a plastic milk jug and a metal washer in between them, then a nylon lock nut at the end.

Almost done! :)

[marcheenek]

Ok, mission accomplished I just need to paint it and make some minor corrections in the future.
Things I like:
- very comfortable viewing while standing, sitting or even lying down
- smooth motion and well balanced - it stays wherever is positioned
- the long binocular bearing arm - it eliminates risk of accidentally kicking one of the tripod's legs, while observing.

Improvements needed:
- there is a slight sway of the vertical shaft - it's just too long - i will reduce the size. It is not really impeding observations, but it's noticeable. I may also think of reinforcing it with additional tubes.
- setting up is a tricky part, preferably a job for two people - there is a huge imbalance when the bino is not attached and the tripod dances around.

I had to add 5lbs of weight on the bottom of the shaft for stability. This is another thing that need to be done... better.

[marcheenek]

I had just few hours of almost clear sky tonight to test the setup in the field.
Here are the options :)

[mercedes_sl1970]

Hi - nice job. Looks like you will have a lot of fun with this bino mount. It's especially a pleasure using something you have made yourself.

Andrew