Altitude Bearings
Tube Fitted, Flat-Sided and Big Bearings Upgrade
Option 1: Small Fitted Bearings with supports cut to your tube diameter.
Option 2: Large Bearings with supports or flat backs.
Option 3: Big Bearings - make 5" bearings 12".

Option 1: Tube-Fitted altitude bearings: For tube telescopes - Dobsonian, Newtonian or SCT. This choice allows you to "Dob" your equatorially mounted newtonian or SCT using your existing rings. Braces on backs of the bearings are cut to fit outside diameter of tube. Attach with 3/8" bolt through a center hole in the bearing. Custom made to any size up to 23" bearinig diameter.

Option 2" Large Flat sided altitude bearings: Fit flat against square or rectangular mirror boxes, typically for 12 inch or larger telescopes.

Option 3: New Big Bearings: If you have 5" or 5.5" small factory installed bearings, the Big Bearings Upgrade provides a "drop in" replacement with a 12" bearing surface. Smoother motion, finer control and greatly improved balance. Requires a drill and Phillips screwdriver.

Small bearings with a lip are up to 11.875"diameter with 11.5" bearing surface - as shown above. Without a lip, up to 12" bearing surface.

Large bearings are over 12" to 23".

Fitted bearing supports are CNC cut to precisely fit the outside diameter of your tube.

Aavailable as a kit or assembled and finished:

Order Here
Select bearing type.
Below items for options 1 and 2 only.
Lip is 1/8" wide by 3/16" tall.
Bearing diameter?
Tube diameter or flat mount?
Finished Altitude Bearings: Arrive ready to use.
Bearing Kits: All parts included. Wooden parts are rough sanded, and pre-drilled. You'll need: Philips screwdriver, sand paper, wood glue, contact cement or spray adhesive.

CNC cut 3/4" Baltic Birch plywood, FRP strips cut to fit with finish screws to attach, #12 steel wood screws. Finished bearings have up to eight coats of fine sprayed polymer sealer with an cinnamon (reddish) tint.