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Dobsonian Goodies

EZ adjust setting circles.
Apertura/GSO motion fix.
Height adjustment stands
 


Image Sharpening Masks
 
Visual: Fix turned down edge.     
Imaging: Remove mirror clip flare.
  

Premium Mirror Cells
for 6" to 13.1" mirrors.

Optimized support points.
Removes mirror-clip distortions.
 

Clamshell & Rotating Rings

For Dobsonian mounts.
For Equatorial mounts.
 
 
Comments & Photos


Updated 11/19/24 
 


Clamshell And Rotating Ring Combinations.
Pricing is for up to 14" inside diameter rings. E-mail for larger sizes.
Mount your telescope without drilling bearing mounting holes in the tube. Each set custom designed to fit your telescope tube.

Clamshell rings close using thumbscrews transversally through one top abutting clamshell boards into a wood insert that cannot pull out. Loosen the thumbscrew to move the tube forward or back, or to turn it for convenient eyepiece position. Rotating rings are contained in a clamshell ring and provide easy smooth rotation of the tube. Rotate the tube when observing low to the horizon and reposition eyepiece upward, or near zenith rotate the tube and position the focuser toward the side.
Clamshell Ring
 
 
Clamshell Ring Small Bearings
  
 
Rotating Rings (with large bearings)
  
 
Extra Ring Set
  
Type Description
 Price
CRK Clamshell Rings Kit
$133
CRKSB Clamshell Rings Kit Small Bearings
$165
CRKLB Clamshell Rings Kit Large Bearings
$183
     
CRF Clamshell Rings Finished
$206
CRFSB Clamshell Rings Finished Small Bearings
$241
CRFLB Clamshell Rings Finished Large Bearings
$264

Clamshell Rings for EQ mounts:

Designed to match your mounting plate hole size and center-to-center dimensions.


Clamshell Rings With Altitude Bearings:
For Dobsonian Mounts.

Clamshell Rings with altitude bearings to match dimension between mount side boards. Requires 1.416" minimum space between tube and side boards.


Clamshell Rings With Internal Rotating Rings:
With Altitude Bearings for Dobsonian Mount
Or equatorial heads matching mounting plate hole size and spacing.

Mount without bearings on an equatorial head, or with bearings on a Dobsonian mount. Combine a clamshell ring and an internal rotating ring. The rotating ring spins freely inside the clamshell rings. Nylon screws through outer rings (top hole in right photo) tightens against the inner ring to preferred friction or locking rotation.


Extra Ring Sets:
Mount Smaller Diameter Tubes In Same Clamshell.

Available for equatorial or Dobsonian mounts. Add additional smaller telescope tubes in the same set of clamshell rings. Quickly attach/detach with four socket head bolts. Left photo: one half of additional ring set removed (shown on ground) and 1/4-20 threaded insert visible in the larger diameter clamshell ring. Right photo: second set of smaller inside diameter ring segments installed.

Options:
Tube diameter:
Shipping Quote Form.
Your Name:
E-mail Address:

Repeat E-mail:
Shipping Zip or Country/Postal Code:

Kit: All parts included, wooden parts are rough sanded with 80 grit, holes predrilled. All parts dry-fitted before shipping. Kits may be shipped worldwide.

What you'll need: Philips screwdriver, sandpaper, wood glue.

Materials: CNC precision cut 3/4" Baltic Birch plywood. Anodized heavy duty aluminum piano hinge. #8 Torx exterior grade wood screws. Clamshells open and close using a 2-1/4" thumb screw that passes through one of the top boards into a 1/4-20 brass threaded insert in the abutting board. Rings have 0.1875" gap at top to allow secure hard-tightening around your optical tube.