I like the stand and you're right that the eyepiece is too low when viewing objects on the horizon. Apparently I got the last bit of Ebony Star laminate (recommended by For this task I followed the directions provided by Stellafane. Sides: Using the Stellarfane directions, I laid … I did not attach a second piece to the front leg at first, however, upon checking the stability, I attached a second piece in a 'T' shape using wood glue and deck screws. Pick one of the two altitude bearing wheels cut out by the router, choose one of the diagonal lines … DIY GOTO Most amateurs these days seem to want a goto scope, and those of us who are into ccd imaging all lust after the AP 1200’s and the Paramounts of the world, however not all of us have the budget for these sort of modern computerized scopes. I used a router and made an arm out of quarter inch ply wood. Lastly, I installed the 1" x ¾" teflon pads with screws which came with the pads purchased from Jim at There are a lot of options for the ground board (see After cutting the board with the router previously described when I made the rocker box bottom, I up drilled the center pivot hole, which must be drilled out to fit the 3/8 inch threaded Tee-nut.
I then removed all but the diagonal masking tape and aligned and center the bearing, clamped it to the cradle, and screwed the bearing in. Advice
Check the squareness and clamp the whole unit for 24 hrs as recommended Ensure the optical tube will fit through the box and the Pressure plates fit into the box and that the circular cut triangles match up with the optical tube (dry run). Lastly I cut the bottom as described previously.I assembled the Rocker box with wood glue and #17 1¼" or 1½" wire brads (four per side). The Dobsonian telescope is simplicity itself: a Newtonian reflector mounted on a basic altaz mount. We will now construct the rocker box portion of this bearing.
To do this I inserted the tube into cradle with the heaviest eyepiece in the focuser along with all tube mounted accessories to ensure its heaviest configuration as recommended by I measured 17¼ inches from the rotation point of the altitude bearings to the back of the tube.I measured the projection of the balanced tube from the center of rotation of the altitude bearings to be 17¼". A dobsonian is just a different type of alt-az mount so, as there are plenty of alt-az goto mounts, all you need to do is get the base motorised as in the Skywatcher Flextube Auto but with decent pointing accuracy. Reply The legs sit under the ground board feet. For my box it was 12¼".The height needs to be approximately 1" less than the maximum height of the Rocker Box after arc for the Altitude Bearing has been cut out. I then attached the arm to the router and drilled a small hole 7.5 inches from the router bit comparable to the nail that will be used to spin the router around on as it cuts through the bearing board. I located 3 screw holes near the edges of the bearing and the corners of the cradle avoiding the corner triangles. I'm building a new dob base for my old Coulter Odyssey 13.1.
to remove the tape I loosened the screws and re-tighten the screws. The altitude bearing braces are custom cut to fit your telescope tube outside diameter. My Tee-nut had a 7/16 outside diameter, and we drilled the center hole to this size. The Box: ¾ inch Furniture Plywood. I'll probably paint mine. I have an 8” dob that I’ve had for a while and I was wondering if i could buy a goto mount for it or if I had to buy a whole new telescope. This method makes a perfect circle where the edges are already squared off.
I added a 5" of margin for a total of 22¼" to allow for additional tube extension for balancing a heavier eyepiece in the future. I've been there.
2 years ago What I ended up doing was installing knobs on the remaining four guide bolts which allowed me to raise the pressure plates evenly and allowed enough room to fit the optical tube though the cradle.Lastly, I applied high gloss polyurethane to the entire cradle and installed felt pads to the circular triangles using gorilla glue.The size can be calculated as follows: (formula from [2] Strips of ¾ inch x 23 inch Ebony Star laminate (good luck finding, see below)For this job you want a nearly perfect circle.
The stand was solid, however, there was a little play when I moved the scope so I decided to do overkill and add more support. For added support, I added two 3/16" wooden dowels (and glued them in) to each joined piece. We have documented our build with downloadable photographs available from the link at the top of this article so you can replicate the parts, but because your choice of drive motor and power supply could differ according to circumstances and availability you may have to adapt the design a little to suit your … Wow looks really nice.
I attached 5" diagonal triangles just below the handle for added strength with wood glue and wooden dowels. Finally I checked to make sure the rocker box rotated smoothly on the ground board.