For a while now i've been wanting to make a camera jib, after a couple tests and some mockups I got some cheap lightweight truss on ebay. Each piece is just over a kilo, 81cm long and 140mm on centre to the tubing.
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| Truss! |
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The end plates have holes in them, but none of them actually line up with eahc other, some are close, but arent exactly ideal.
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| Not what i'd call accurate :| |
For the first test the holes were matched as best as posisble and drilled out from M4 to M5 so they lined up properly. With everything bolted together, there was still some flex in the joints and the alignment still wasnt perfect.
New plan, fabricate something similar to an egg.
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| A raw egg, honest |
Instead of using the plate as the joining surface, making a spigot or egg in each tube will drestically improve strength and the stability of the jib. Fitting them is a pain as some of the tubing had been knocked over the years so wasnt round in places and has to be fixed first. The holes also need to be fairly accurate, and in lieu of a large drill press, this will have to do:
Not exactly high tech, but it works. The drill and stand are about as old as i am.
The eggs fit permanatly in to one piece of the truss with an M5 bolt and a locknut as they'll likcely not need to be removed often or hopefully at all once finished.
The other end has to be tapered so it'll fit easier in to the next piece of truss.
This is what happens when a drill bit explodes, i didnt find any of the other bits. This was the 3rd drill bit of the day to be broken or ruined, although the only one to spontaniously atomise in use (one was blunt within seconds, one snapped in half)
Few hours work in total, all the bits join together and its amazingly rigid compared to how it was. Next stop, the pivot and counterweight-come-handle end.
