Dobsonian Telescope Altitude Bearing

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Altitude bearings for small Dobsonian telescopes consist of mounting holes to screw onto wooden cradles for optical tubes. The bearing diameter is 150mm; width is 25mm. Light sanding of bearing surfaces may be necessary to remove print artifacts. UPDATE 6/29/2018: Finished photos are added, along with new parts - a clip to attach an 7/8" velcro strap and sleeves for the azimuth bearing. The sleeves fit in 1/2" holes and accommodate 8mm screws. The mount is made of 1/2" plywood except for ground board feet. Azimuth bearings are 16" in diameter, while formica-faced bearings ride on three 5mm teflon furniture glides. Weight is entirely on the glides, making action smooth in both azimuth and altitude. A 6" f/8 homemade scope with a ground mirror has been tested to better than 1/8 wave. UPDATE 7/1/2018: Screw slots replace holes for bearing adjustment ease. A hub insert allows precise alignment of bearing centers with telescope cradle edges. All dimensions remain the same, only screw hole configuration changes.