Home made wooden tripods

Home made wooden tripods

I didn't have a lot of money when I first got into back in highschoool in the 1980s, but I wanted a tripod so I could experiment with longer exposures in low light. I didn't want to spend a lot of money. So I set out to build my own.

I built a tripod out of wood, and later a more refined version of it. This page details some of the things I figured out and hints if you want to build your own.

Second tripodfolded up

Leg sliding dovetail joints

One of the things that helped make the wooden tripods possible was my dad's at the time new Felder table saw with a tilting spindle shaper. There was also a thin 30-degree cutter head that was actually part of a sort of panel joining cutter assembly. By using this cutter, and tilting the shaper spindle, I was able to cut out most of the 30 degree dovetails in a few passes. Using the shaper worked better than a router would have, on account of better chip removal, and not having to worry about the cutter overheating from a full depth cut that is always necessary with a dovetail bit. The other thing I realized much later is that 30 degree dovetail router bits are actually kind of rare. I guess 30 degree is not ideal for most normal dovetail joinery.

For the first tripod I built, I made the legs out of two segments. But I figured this tripod was a little too bulky to take with me to University, so I built a second, lighter tripod with legs that consisted of three segments.

The middle segment has two female dovetails cut into it, and the outside pieces are each a male dovetail. To lock the legs, the female dovetail is clamped together with a screw and wing nut, one on each end of the middle segment. With this clamping action, the dovetail forms a rigid joint.

I needed some way of keeping the dovetails from sliding all the way apart. I couldn't really figure out a good place to put a catch on it without making it ugly or interfering with the wing nuts on the sides of the legs. So I came up with this clever little spring loaded catch. At left, the top segments shows the spring loaded catch and the bottom segment shows the wedge shaped notch that it catches in. The catch is normally retracted, but a spring pushes it into the notch when the notch slides by.

Shown at left is the catch removed from the leg. The catch is just a rectangular piece of wood in a rectangular hole, with a spring behind one end of it to push it out. In retrospect, I should maybe have made the catches a little bigger. I have never had them fail on me, but then again, I don't treat the tripod overly rough.

For my first tripod, with the legs of just two segments, I didn't need catches like that. To extend the legs on that one, I'd just loosen the wing nuts, and lift the shoulders of the tripod off the ground to the right height and tighten the wing nuts again. So the legs joints never over extended and came apart. But for the tripod with thre segment legs, raising the tripod by the shoulder would just slide one of the dovetails all the way apart without extending the other divetail. So some catches were needed so that after one segment is fully extended, it won't go any further and the other segment has to extend.

Cutting the sliding dovetail joint on a table saw

Because 30 degree router bits are are not something you can get in most stores, I decided to experiment with making a 30 degree dovetail joint on my table saw, using a technique vaugely similar to what I had done with my dad's shaper.

Making a finely spaced series of cuts did the trick. But it took on the order of 20 passes to clear out the dovetail to make it reasonably flat on the bottom. The bottom of the dovetail is always cut with the corner of the sawblade teeth. Perhaps it might be a good idea to take a cheap 7 1/4" circular saw blade with teeth at alternating angles, and break or grind off the carbides for all the teeth facing in one direction, so the saw blade's bottom of cut would be at an angle.

I cleaned out the bottom of the inside dovetail joint with a chisel to make it reasonably smooth.

The outside dovetail could be cut with just two passes on either side.

Finally, I beveled all the sharp 60 degree corners. There's two reasons for this. The first being that the saw blade would not reach all the way in on the inside corner, the other being that these sharp 60 degree corners are very uncomfortable to hold, and just generally vulenrable to damage.

And finally, how it all fits together. Enough of a gap left for it to slide easily but not pop apart.

Home made tripods: shoulders and head

Tripod shoulder joint

For 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.

I used some 1/8" steel shafts from some random piece of machinery that I had disassembled. The shaft is rigidly fixed in the shoulder via two screws on either end, and passes through two holes in the leg segments. The holes are sized so that the shaft fits in them rather tightly - I had to drive them in with a hammer.

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.

The shaft that I used is actually a very large framing nail. The sort of nail is sometimes used in timber frame construction. These can be obtained in single quantities in some hardware stores that sell nails from open boxes by the pound. I found the nail had the right degree of hardness and workability to be able to bend to 90 degrees without breaking. However, I did have to cut a few relief cuts into the nail with a hacksaw prior to bending.

INCLUDEPICTURE "http://www.woodgears.ca/tripod/nail_bent.jpg" \* MERGEFORMATINET With the relief cuts in the nail, bending could be achieved by clamping it in the vise, with the first relief cut at the edge of the vise, and just bending it over with a heavy hammer.

Camera screw

The 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: