Home made tripods: shoulders and head
Tripod shoulder jointFor the first tripod that I built, I just made the shoulder joint out of a piece of 3/4" plywood. For the hinging action, I just screwed a screw into either side of each end of the Y shaped shoulder piece. You can vaguely see this in the image at right, which I took shortly after I built the tripod and was using it to take photos with blueprint paper.To lock the tripod shaft, I just had a lever which formed a sort of cam to jam the shaft. This shoulder joint didn't last overly long. I found that the plywood was not hard enough, and the screws and do so rigidly. So I rebuilt the shoulder joint, this time using 3 cm thick piece of solid maple. I also replaced the cam locking mechanism with a thumbscrew for securing the vertical shaft. This allowed me to clamp it more securely.
Note that the screw doesn't push directly against the wooden shaft. Instead it pushes against a rectangular
piece of metal, which pushes against the shaft. That way, the end of the screw doesn't dig into the
tripod shaft.
But even with the screws holding the legs screwed into hardwood, I found that with seasonal changes in humidity, the legs still ended up getting a little bit loose over time. Also, I wanted the shoulder piece to be smaller for my second tripod, so I came up with another method for that one.
The tricky part with doing it this way was drilling the holes for the shaft in the shoulder piece. The grain of the wood tends to pull a thin drill a little, especially when the grain is at a 60 degree angle with respect to the drill. So I used a thicker drill. I also drilled from both ends for each hole, so I wouldn't have to drill as deep. The holes still didn't totally align where they met, but close enough. With the hole being perhaps 1.5 x as large as the shaft, I needed to use screws to hold it in place. The screws act more or less like set screws on the shaft. The other refinement was to use a piece of galvanized steel pipe to hold the shaft. That way, I could make that part a fair bit smaller. The thumb screw is threaded into an aluminium block attached to the steel pipe. The tripod shaft has a flat side where it faces the screw, and a piece of steel is in between the end of the screw and the shaft, inside the pipe, to keep the end of the screw from digging into the wooden shaft. The flat part of the tripod shaft allows room for this piece of metal. This shoulder joint design hasn't given me any problems since I built the second tripod back in 1988. Making the tripod head
I spent a bit of time coming up with the tripod head when I built my first tripod. When I built the second one,
I really couldn't think of a way to improve on it, so just built the same head again.
The key piece of the head is a 3/16th shaft bent at a right angle.
Panning is achieved by the steel shaft turning inside the tripod's shaft. Pitch and roll are achieved by the clamp
turning on the shaft, and by the clamp turning about the screw with the wing nut on it.
The block with the wing nut through it is actually two parts, so that tightening the wing nut will tighten
the aluminum brackets, as well as tightening the head on the shaft. The wing nut fixes both pitch and
roll at the same time.
Camera screwThe only other tricky bit to making the tripod head is the screw for holding the camera. The standard tripod thread is a 1/4 inch thread with a fairly coarse pitch. The tricky part is making a screw that will not fall out of the tripod. For my first tripod, I started with a screw that already had a captive washer, and epoxy glued a wooden handle around the hex head of the screw. For the second tripod, I used a brass 1/4" screw. I filed it down to a narrower diameter for part of its length, then took a washer with a small hole and cut that open to a slot to fit around the screw. With the washer glued to the tripod head, the screw still has freedom to move, but is captive to the head.For an old Manfrotto tripod, where the screw was missing, I used yet another approach. I just filed a notch into the screw and put a snap ring on it. A snap ring is one of these doohikeys:
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