Cannot believe it took me over 30 years of observing to finally get around to building this. After 2 nights using it , I am spoiled rotten, I could never go back to tripods and stiff necks for binocular observing. And certainly not hand-holding binos.
90* alt & 360* azim motion.
Intuitive hi-tech azimuth drive system (one ski pole )
12" dia lazy susan bearing, 1000# rated, smooth as silk with my weight on it. The slightest push with the pole rotates me to position.
Bino mount adjusts for body size , angle, & eye relief.
I may eventually do a fancier bino clamp but for now the zip-ties seem to work fine.
Dimensions: 3"x20"x33" 22# all parts. 14# chair.
Parts/Costs: (for me, ~$20 plus the chair)
1/3 sheet 3/4 ply (had on hand);
some nesting alum tube parts (from a batch of surplus electronics i bought years ago);
L susan bearing ($16 on ebay);
maple blocks (cut from my firewood pile);
misc fasteners ~$3;
**X/Y level $1;
a couple 1# dive weights (had those).
You can find the zero-G chairs for around $40 if you dont have one. This one was a $7 thrift store catch, it is more comfortable that the $40 i bought earlier.
A few tips-
--base assembly- LS bearing screwed to ground board; mid-board screwed to bearing via access holes in ground board; top(chair) board screwed to mid-board from above & below. NOTE the chair board is NOT centerd over the bearing !, your COG will be offset to the rear so the loaded COG of the chair is what gets centered over the bearing ! See pics.
--don't skip the **X/Y level. The base MUST be set up on a level patch of ground to prevent gravity from constantly rotating you to the low point !
--you need to have a way to fasten the chair to the base, i screwed on two strips of wood to tightly fit the rear chair foot between and then match-drilled thru the strips & chair base so i could lock the chair in place with a couple large hitch-pins as shown in the pics. Those strips and pins also allow me to attach the aluminum tubes to the base for carrying or storage. Just drill the tubes to match the holes in the wood.
--I leave the maple blocks on the chair so setup is under a minute- insert the tubes in the blocks & tighten wingnuts; place chair on base & insert hitch-pins; slip the bino-board onto the tubes; and climb aboard.
--not shown are rubber friction washers cut from inner-tube, between the rotating joint of the blocks
--bino holder board is cut from 3/4 cedar for light weight. Cutouts on it give good hand access to bino focus without having to move the binos forward
--lead counter-weights simply hang in holes at rear of tubes. Can use whatever wgt is needed. 1# wgts seem good for 10x50, 11x70 binos . Might have to go to 2# wgts when my 20x80's arrive.
--nylon screws on outside of bino board lock the sliding alum tubes in place to hold proper eye-relief. This is important espec with heavy binos when viewing at high angles, you don't want to wake up in the morning looking like a racoon !
First experiment (daylight) to set the rotating blocks at the right up/dn position on the chair to adjust for body size (butt to eyeball measurement). Mark the block position on the chair frame so you can return to it easily. I added a bit of ruler tape to the chair tube so i could easily set it for myself or others.
Bino angle & eye relief are adjusted on the fly as you observe at varying altitudes.
You can easily reach the base board space under the chair while sitting. as it rotates with you, its a great out-of -the-way safe space to store gear while observing. I am going to add a holder for a thermos and coffee cup to one side of the base.
Anyone who spends much time with bino's deserves one of these. It is a complete game changer for bino observing. No getting up to reposition tripods or chairs, just sit there & scan the entire sky for hours on end.
What a joy to just kick back and soak in the sky with complete freedom of movement to any destination that strikes my fancy. After 2 nights I can already see this contraption is going to seriously cut into my telescope time.
I still enjoy the porthole views thru my scopes, but this very different. It is more like a space-walk experience than an observing experience. You literally get the impression you are floating among the starfields as you move from place to place. If i had to describe the experience in one word, it would be " Immersive" .
Last night i actually nodded off while floating between Cassiopeia and the Double Cluster !
Now, if i could find a way to mount my Dob on this thing
pics below & following posts