astronomyasylum.com    Homebuilt Astronomical Equipment and Observatory

This was a design that I really liked but eventually abandoned. I found an old office chair and used it as the azimuth axis. The altitude axis is just a large fork. This design used traditional type Dobsonian bearings (pvc plumbing pipe). The OTA had a smaller draw tube (I've since upgraded to a 2" focuser) and was built of lighter wood (primarily pine bed slats). I liked this design because it was extremely portable and I thought it looked good, however the azimuth axis gave problems. The plunger that rotated inside the office chair base wobbled as it turned. I tried fixing this my wrapping Teflon tape around the plunger, but in the end couldn't achieve a smooth rotation.

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Office Chair Truss Mount

I experimented with an interesting looking fork design that used old legs from an infant changing table. I really liked how this design looked, but abandoned it because it wasn't strong enough to tilt at an angle when wedge mounting the telescope for astrophotography. As a plain Alt-Az mount, the fork functioned fine.

 After I decided to switch to a friction drive system, I tried to find a way to retain the office chair as a base and retrofit a roller bearing system to the azimuth drive.  I was planning to incline the circle under the rollerblade wheels but this never got past the initial testing phase. In retrospect this was one of those "what in the world was I thinking" type designs. It proved too unstable and was abandoned. The office chair base was finally taken to the recycling center.