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Some features of my 22" f/4 telescope





Mounted mirrorcell with cooling fan.    The cell was fabricated based on Kriege and Berry's book



Mirror
                Cell

Mirror cell (photo taken during the re-finish project and nothing was done to the cell during this project, just taken out of the mirror box.)  1/4" aluminum flotation triangles and bars.  The frame was fabricated with 1" tubular steel and 1.25" flat steel on the sides.  The white flotation pads are the original furniture glides.  They are nice and slippery.  The black flotation pads are the non-slip hard rubber, so the mirror will not shift laterally while on the sling, especially when the scope is near horizontal and on the equatorial platform.



Lower
                Clamps
Lower Truss assembly (one knob per pair!)


lower truss
                clamp

Lower truss clamp - top view


Lower truss
                clamp-inside
Lower truss clamp - inside view


Lowere
                truss clamp
Lower truss clamp - compression part.  I took it off and put on top of the mirror box for illustration purposes.   This part is very hard to make properly.  The main holes were drilled with a Forstner drill bit on a  good drill press.  Need to calculate the angle of the trusses before starting this part...otherwise everything will be messed up.  Learned the hard way when I made these for the first time for my 16" project.   Used a level and digital protractor to make sure that the drill press platform is angled right.  Don't use the markings on the press, it is utter crap.   It is made with 5 pieces of 1/2" Baltic Birch glued together.  




Unique ball and socket upper clamps.


upper
                truss connector
Upper truss connector detail.


upper truss
                connnector detail

Upper truss connector detail.  From left to right; 1" Phenolic ball with brass threaded insert, lock nut, large washer (slightly larger than the diameter of the truss itself, smaller washer just small enough to fit inside of the truss (to prevent the connector from moving laterally as the tube insert is not strong enough to prevent lateral movements), regular nut.  All of this is one a regular threaded rod.  I used 5/16-18 threads.
Phenolic ball is available here.   Nuts, washers and threaded rod is available at your local hardware store.


tube
                insert

Tube insert inside the truss.  I got mine from a place I don't remember.


Upper
                Truss Assembly

Upper
                Truss Assembly

Upper truss clamp assembly (side and top)





Upper Cage (1/2" Baltic Birch with 3/16" Baltic Birch focuser board)  Very light!


Focuser
                Board

Detail of the focuser board.  I used 3/16" Baltic Birch plywood.


22"
                rocker box

Front end of the 22" mirror box and rocker box.  The four furniture glide feet on the "front" side of the mirror box is there for support during unloading or loading.  When I load or unload the mirror box, I actually place it standing vertically on the ground on the "front" side, so it is easier for me to pick it back up. 
I transport my mirror box without the mirror in it as it is transported in it's own container. 
I used solid wood plugs to cover the screws.  Looks very nice. 
The mirror box was slightly oversized to handle the lower truss clamps mounted on the inside while keeping the trusses totally parallel.  Also increases the girth of the entire assembly for stability.
This telescope is buttery smooth!.



22"
                side

Same assembly as above, but from the side.  The bearings were made by Obsession for their 18" telescopes.  I decided on these instead of the larger bearings as the larger bearings has a notch for trusses that are mounted on the outside.  That would not work in my application.  The diameter is a little smaller than I wanted, but my telescope is light enough so it is still buttery smooth.  In fact, this 22" telescope weighs less than the 18" Obsession.  You can get the bearings here.


22 inch
                stored
This is how I store it when not in use.  The duffel bag inside the mirror box is my "cold gear".  This duffel contains enough layers for cold nights down to 10F.  Note:  The primary mirror is NOT in the mirror box, but inside it's own storage box.  I transport the mirror separately, so I can lift the mirror box without wheelbarrow handles and load it in my vehicle.  I can load my vehicle in less than 10 minutes with everything needed for an observing session up in the mountains.  No wheel barrow handles and ramps needed.