I finally made a binocular mount for my faithful
Celestron 15x70s
. It's a parallegram mount with five degrees of freedom: (1) the whole thing swivels where it attaches to the tripod, and (2) goes up and down; the binoculars then swivel (3) up and down and (4) left and right, and (6) can rotate a bit side to side. It sits on a very short tripod as it's designed to be used by seated me and standing children.
Total cost was quite low. The long dark pieces of wood are pieces of a recalled cherry crib that was being given away for scrap wood on Craigslist. Most of the rest of the wood is 1/2" Baltic birch leftover from the 6" F/5 made for my friend, for some parts laminated to approximately 1" thickness. There are a bunch of 1/4-20 carriage bolts and knobs from Amazon's
Industrial and Scientific store. I had some leftover PTFE for the main azimuth bearing, and purchased some cheap PTFE washers from Amazon for a low price (the price has now gone up by an order of magnitude). The hideous counterweight is a bubble wrap envelope full of sand, duct taped all around. The first iteration used a brick, but I was worried that a kid might whack someone on the head with it, and so bubble wrapped sand is better.
It was pretty easy to make. I used a router for some round pieces, like the semicircular binocular attachment, but polygonal pieces cut with a hand saw would have worked just as well.
The azimuth bearing was the most complicated part. It's basically scaled-down Dobsonian azimuth bearing: there are three PTFE pads inside, which ride on a CD (two out of my three Dobsonians ride on vinyl records). This then bolts to tripod platform.
The tripod is entirely home made, too. I once ended up buying twelve feet of 1.25" PVC conduit at Home Depot or Lowes because I needed a few inches worth for a focuser. I expected I would eventually find a use for it, and hereby I did. The tripod platform is a round piece of 1/2" Baltic birch, with some square poplar rods glued underneath, between which the PVC legs sit, attached with a carriage bolt. To keep the legs from sliding apart too much, I glued three pieces of webbing, I think scrapped from a car seat or feeding seat, glued to the legs with Shoe Goo, and then screwed into place for additional safety.
I may later make a post with more detailed photos, but it was all fairly simple. One thing that took me a bit of time to figure out is the brown block of wood that the semicircular binocular attachment attaches to. It is a rectangle of cherry, with an up-down 1/4" hole and an across 1/4" hole. The latter hole has a permanently mounted carriage bolt. I used a 5/8" Fortsner bit to dig a deep well for the head of that bolt so that the up-down bolt would be able to sit to the left of that head. I then filled the well with JB Weld for strength.
