Scotch Mount/Barn Door Tracker
Click on the picture to see a larger version.
Here is the scotch mount/barn door tracker I built based on plans from the following two web sites Link #1 , Link #2. I used wood I had laying around the house, the only items purchased were two hinges, the tangent screw, t-nuts, and some springs. I spent around $5.00 total and have to say it was the best money ever spent. It's amazing how something as simple as this device can really work to improve photography of the night sky. Some day I may attempt building a double or triple arm mount and even motorize.
| Here is a wide angle shot of the scotch mount on my tripod. For those interested my tripod is a Giottos MT9180. | 
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| Here is a close up shot, you can see the springs I added instead of using rubber bands. The springs are a new addition so I haven't had a chance to test that idea. I also plan on putting a small flat aluminum strip I have where the tangent screw's head makes contact with the top board. I'm hoping this will help ease the friction and make the turning of the screw smoother. At the bottom of the tangent screw you can see a red twist on wire connector, this was a large size that screwed onto the screw rather easily. This provides a very nice handle to use in turning the screw. | 
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| Here is another angle on the mount that shows the dial a little better. | 
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