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Telescope Mirror Holder Cells, 3 point to 36 points

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Use the Mirror cell quote page on the HOME page to determine your mirror support requirements, size, shape, weight, etc...

Mirror cell design is pretty strait forward. Your mirror diameter and thickness determine the number of supports that would best hold the mirror in gravity equilibrium.  A thin mirror will need more supports to maintain the conic curve figure of the mirror. A thicker mirror might beable to use fewer supports but never short your mirror. Use 9 or 18 supports as a guide line.

Mirror cell layout with no glass edge protection
13in-opencell.jpg
Mirror cell is open around the mirror. Edge clips are not shown.

Mirror cell with edge band to protect the glass
13in-ringed.jpg
A band can be used to protect the glass from chipping

 
Mirror and Support Point Cells
 
Here are some autocad drawings showing each of the 6 to 54 point support rocker arm layouts. You can use PLOP.exe to design your own cell layout. Find PLOP.exe by using google search for "plop telescope".  Standard mirrors can usually work well with 9 point suspensions.  If your mirror is larger then 10" you should use edge protection and 18 point or more suspension points.

6 point PLOP calculated Mirror Cell Layout
3d-6pt.jpg
This might be good for mirros less than 8 inches

9 point mirror cell support from the PLOP Model
3d-9pt.jpg
This is my standard for thick or thin mirrors larger than 10 inches

18 point cell with triangle rocker 3 pt. pads
3d-18pts.jpg
This cell would be good for thin mirrors larger than 10 inch. You can modify this to a 36 pt. Cell

More Mirror cells designed using the PLOP calculator for glass mirrors.

27 Point Mirror cell design
27pt-cell.jpg
This is a log of points but still seems duable

A bad 36 point mirror cell design and layout
36ptcell.jpg
You probably dont want to do this confusing a cell layout. There is a better solution to a 36 point

Mirror cells usually need fitting to your mirror shape and tube ID. Fill out the details of your mirror cell holder and back plate so the design will be to your liking. 
 
Below is shown some 16" all aluminum mirror cells with and without a protection edge ring. You can add a 12 vdc 2" muffin fan in the middle for air cooling circulation.
 
The 16" cells shown weight about 15 lbs or less.
 
Each mirror cell is design to fit your tube, box, or backplate holder requirements.  The total weight of the mirror and the cell must beconsidered when retrofitting your telescope.  This will keep the Center of Gravity of the whole telescope close to where it was.
 
Mirrors larger then 20" should probably go to the modified 18 point cell where rocker arms with 2 points are placed at each triangle pad corner making a 36" flotation cell.

16" 18point Cell
yring.jpg
This is a Double "Y" type cell with protector ring

Light weight 16" mirror cell with protector ring
18ptcell.jpg
Cell has center fan, 18 point suspension pads

18 point cell can be used upto 20" Diameter
ynoring.jpg
Open 16" Cell with no ring

More symetric 36 points Cell
36pointrockers.jpg
32" Mirror cell with 36 points.

An early fiberglass and wood mirror cell for 12"
12fiberglassmirror.jpg
This uses 18 point supports on rocker arms

Mirror Cell 16" with 18 points, 15 lbs
12lbscell.jpg
All aluminum mirror cell with ring protection

Machined Al. Casting of a 6" Mirror Cell
6incell.jpg
You can drill holes for air cooling flow, add 3 point suspension, adjustable tube back plate

Precast machined Al. 4 inch Cell from casting
4incell.jpg
Modify cell as needed, holes for air cooling, 3 points, adjustable tube mount back plate

8" precast miror cell using 6 point suspension
8in6point.jpg
Note each Rocker is 2 points around the 70% circle. You bolt this to your existing back plate.

Finished 18" with 18 point suspension, 20 lbs
18in-cell.jpg
This was for an 18" Cassigrain for Eric in France.

Hooker 16" mirror cell in the tube
16incellintube.jpg
Rear view of 16" mirror cell with 18 points

Cast Aluminum Mirror Cells have this same design.
10incell.jpg
10 inch mirror cell and back plate spider.

MOSI Museum 17.5" Mirror Cell with 18 points
mosi17cell.JPG
MOSI Dobsonian mirror cell layout.

Center Mount Plates for Mirrors with Center BOLT!!
8incentermnt.JPG
Two spring loaded plates. Just bolt your mirror in the middle.

Aluminum 8" mirror cell with 6 point rockers
8in6pt.JPG
Mirrors up to 10" may work ok on 6 points.