One day, while filming something outdoors, one of the bottom legs of my camera tripod fell out of the corresponding middle leg. This happened in a gravel and brush area and I couldn't find all the parts - or at least I couldn't put back together what I did find. Rather than wastefully throw it away and buy a new one, I decided to repair it.The photo on the left below shows the tripod and detached bottom leg along with the two parts I used to fix it: a short piece of plastic electrical conduit and an adjustable furniture leg, both of which I already had. I needed the conduit because I needed something thick for screwing the furniture leg into securely.
The photo on the right shows the finished result with the conduit fitting snuggly onto the end of the middle leg, the bottom leg inside the middle leg and the furniture leg holding the bottom leg in place by pressing firmly against it.
I first cut off a more-or-less randomly selected length of the conduit using my hacksaw. In the photo on the right below you can see that the round hole in the conduit is too small to fit over the tripod's middle leg and was the wrong shape. This was on purpose. I wanted it to go on with a tight fit.
So I got out a round file and started enlarging the hole in the right places so that it would be a tight fit. The photo on the right shows the result.
I next needed to make a hole in the side of the conduit that I could screw the adjustable furniture leg through. This meant I needed to make a hole and that I needed to make screw threads in that hole.
To do that I needed a tap and drill set (see photo on left below.) Luckily the furniture leg was 1/4" and 20 threads to the inch, a very, very common size and I already had just the set for it, one that came with a 13/64" drill bit and a 1/4"-20 tap.
I started by drilling the hole.
Next, to make the threads I needed a T wrench, which I already had (see photo on left above and photos below.) I inserted the tap into the wrench and proceeded to make the threads.
In deciding where to drill the hole, I knew there was already a hole in the form of a slot in the middle leg that I could take advantage of. The photo on the right shows me sliding the conduit over the middle leg and how the hole I made lines up with the slot in the leg. Having this slot there already was important because in a previous so-so attempt to make a repair I found out that this tripod's legs were a hard metal and that my drill bits are a bit worn out. Having an existing hole was useful.
In the photo on the left below I've screwed the furniture leg in a bunch so you can see it inside the middle leg. It's the end of this furniture leg that will press against the tripod's bottom leg and hold it in place.
And below is the finished result, which works great!