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For the 2017 solar eclipse I wanted to build an indirect solar viewer. This article isn't about the solar
viewer (spoiler alert, it failed due to having the wrong aperture size), but about the tripod that I built to
hold it in place.
I wanted my tripod to have three adjustable legs, a head that could rotate 360 degrees, and an arm to adjust
the viewing azimuth. What I came up with is a bit fiddly to setup, but the positioning was rock solid.
For building what I'll call the head of the tripod, I used scrap 1/2" plywood and two 1-1/2" by 3/8" bolts with
associated nuts and washers. First, I cut the base of the head to 4" x 4" square. I then drilled a 3/8" hole
in the center of the base for the rotation bolt. Then, I cut a 4" x 3" plywood piece and drilled a 3/8" hole
in its center. Next, I cut out two 1-1/2" x 4" strips. I clamped these together and drilled a 3/8" hole at
roughly 1/2" in from the side and 1/2" down from the top edge. These pieces will make the azimuth
adjustment. I rounded the corners of one end of one of the azimuth adjustment pieces to allow it to
pivot without rubbing against the base, see Figure 1 below. To allow the use of zip ties to attach
the indirect solar viewer, I drilled three 1/4" holes about 3/8" down from the long edge spaced roughly
every 3/4" on the piece with rounded corners. This step can be skipped or altered based on what you
intend on attaching to the tripod. Finally, using a hand saw and some scrap 2-by material, I cut three 1-1/2" wide x 2" 5 degree wedges that will give the legs of the tripod some splay.
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Figure 1 - Azimuth Arm
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To assemble the head, I put one of the 3/8" bolts into the hole on the 3-1/2" wide piece and then clamped
the unrounded 1-1/2" wide piece to it so that the edge of the bolt head was held from turning by the
narrow strip and the bolt hole was on the far edge from it.
With the pieces clamped together, I then
removed the bolt and drilled pilot holes from the bottom of the 3-1/2" wide piece. The holes weren't
counter sunk since the screw heads will be hidden and a washer will separate this piece from the base.
With the pilot holes drilled, I unclamped the pieces to apply wood glue and then screwed them
together. With that done, the arm can be bolted. Next, the wedges need to be glued onto the base
120 degrees apart from each other with the thick of the wedges toward the center hole.
For making the tripod legs, I ripped an 8' x 2" x 6" piece into 3 strips with my table saw fence set at 1-3/4". To
make the legs adjustable, I wanted to use a lap joint with one leg holding two bolts fast and the other
leg having a long slot for the bolts to ride along. I built legs for 2 tripods out of this 2" x 6". I cut each of
the 3 strips into 4 equal lengths using a radial arm saw. I wish I'd had access to this while cutting my
wedges! To cut out the lap for each leg piece, I set the table saw fence to 7/8" and cut a through cut 6"
long on one end of each leg piece. Then, using a jig saw I finished cutting out the waste for the lap
joints. Then I paired leg pieces together to drill three 3/8" holes through the mated lap joints approximately 2" apart with the first hole 1" from the top edge of one of the pieces. Then I separated
the pieces to connect the three holes on one leg piece with the jig saw to make a slot. The paired leg
piece can then be bolted together using the top two holes on the piece without the slot. This gives you
enough adjustment to level the base in most places where you'd use the tripod. Repeat for each leg.
With the legs built, you can screw them to the base from the top of the base through the wedge. The
legs will be splayed by the angle of your wedge. Next, you can attach the head to the base using another
bolt with a washer between the head and base so that it can rotate evenly. The nut on the bottom of
the base will be a little tricky to screw on. I use a pencil eraser to start the nut and then a deep-well
socket to hold the bolt still and spin the head to tighten the nut.
Now you have a completed tripod.
I am a hobby woodworker with a garage workshop. I built an oak desk back in high school and a couple
of bird houses before that. In my current workshop, I've built some hardwood mallets, a dice tray, toys,
and shop furniture. With two boys under 4 years old, my shop time is limited, but soon I hope to get
in there more often. I can be reached directly via email at thoi412@gmail.com
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