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In the late summer of 2004, friends and I were getting
ready for an annual cottage weekend and there was talk of cooking a roast
over the open fire. When it was decided that we needed a spit that would
span the fire pit, I said I could make something that would work. All I
needed was a motor, a bar for the spit, and something to prop the whole
thing up. At first, we thought that we could take turns operating a crank
but this was ruled out as being too impractical. What we needed was some
kind of motor drive for the thing. I had discussions with Manny (our chef)
and we went to a hardware store and picked up a motorized spit for a gas
barbecue. This solved a number of requirements all at once but introduced
one of its own. The solved requirements were the motor, the bar and the
spiked clamps used to hold the meat on. The new requirement introduced
was the need of an extension cord long enough to reach from the cottage
to the fire pit. I would bring that one myself. So now we're all set to
cook a roast - almost.
We still need to hold the spit up off the ground,
and this is where the design effort comes in. I wanted something that could
be adjusted in height so we we could take into account the size of fire
were to deal with. For this, I thought a couple of old camera tripods would
work well. All I had to do was make minor modifications to the spit
fittings then bolt them onto the tripod heads. Here is a photo of the
setup
at this stage of development.
Since the tripods would be positioned very close
to the fire, they needed thermal protection and for this I used some old
TV dinner trays and fiberglass
insulation. These protective barriers were held together and tied to
the tripods using heavy wire, disc clamps from old hard drives and pop
rivets.
The system worked quite well and after 5 hours over
the fire, the roasts were superb. Our chef Manny prepared the meat ahead
of time with his own marinade and everyone stoked the fire and added wood
when necessary. To see early and nearly done roasts, click on the thumbnails
below.
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