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For the past few days I was lucky enough to attend a training with SCA’s New Hampshire Corps! I’m a member of the Hudson Valley Corps, which is a group of 40 or so conservation interns in the Hudson Valley, from Albany down to Long Island. We meet up for training and service projects every month or two, but generally live and work pretty separately, though there are three interns at my host site (one of whom is my roommate.) The New Hampshire Corps is COMPLETELY different. All 30 of them start out at Bear Brook State Park, outside of Manchester, and live together in adorable CCC cabins for the first half of their internship. Later they split up but a lot of them remain in teams, working, living, and eating together. My supervisor and I had a great three days staying and training with them!

20150617_172347 - CopyThis was our cabin! 
20150617_075441 - Copy

This is the lodge where they have their meetings and meals- it was very communal. At first I was a little uncomfortable since I’m used to making my own meals and retreating to my private room at the end of the day, but as I got to know the NH corps members, I had a lot of fun!
20150615_143445 - CopyThe training we went for was trail rigging: using things like hoists, pulleys, and physics to move large objects like rocks, logs, and stumps. First we had to learn a few basic concepts: here we have the SCA member on the left pulling the weight of the four in the center. This is done with mechanical advantage: using ropes and a few pulleys (blocks) 100 pounds of force can move over 400 pounds of load. Of course, rocks and stumps can weigh more than 400 pounds, which is where the grip hoist comes in- it can exert much more force than a person or several people, and has more safety features. Granite (which New Hampshire is full of- one of their mottoes is The Granite State…. the other is Live Free or Die) weighs about 175 pounds per square foot. Rocks large enough to be used as stairs or stepping stones across a river are very hard to move!

20150615_154255 - CopyHere we have one of the New Hampshire corps attaching a line to a HUGE chunk of granite. The first few days we spent learning concepts and dragging large objects across the ground.20150616_110719 - CopyTo gain mechanical advantage, we had to use multiple blocks on sturdy anchor trees. In this picture, the hoist is off to the top right, and the load (huge rock) is off to the bottom right. It’s hard to get a whole rigging system in one picture, because the load and the hoist can be far away and in different directions- you don’t want to be hoisting a huge rock directly at your face! (by the way, the difference between a winch and a hoist is that a winch is largely designed to move horizontally and spool the excess line up, a hoist can move in any direction, including vertically which will come in handy, and spit the excess line out the back.) The slings around the tree can hold hundreds if not thousands of pounds of force, since the blocks can double the amount of force the hoist is exerting on the load.
20150616_143638Remember how I said hoists pulling vertically would come in handy? The third day of the training, we learned more advanced, highline systems. Dragging thousands of pounds of rock across the forest floor can damage the ecosystem and be very impractical when there are lots of other rocks around, so sometimes it makes more sense to lift the load up and fly it through the air to its destination. This requires a lot more consideration than just dragging along the ground- if the sling around the load slips off while dragging, the rock would probably stop. If the sling slips off while the rock is flying, it could crash down, roll down a hill, just generally be bad news. There are also more physics around which I won’t go into!20150617_134810

Considering a rock- is this a good shape to fly? Will the line, blocks, hoist, slings, etc be strong enough to hold it? Will we be able to get it to the loading zone? Will it be useful at the unloading zone?20150617_144334 - CopyAnd the results! Hundreds of pounds of rock flying through the air! The upper line is attached to the hoist at one end and a sturdy anchor tree on the other end, the bottom line is the belay line- just like in rock climbing, you want to have extra safety and be able to control the load’s descent. We flew several rocks this size or bigger down our line- it was about 200 feet long and crossed a valley that would have been very inconvenient to roll or drag the rocks across.

All in all, it was a very exciting, interesting, and challenging training, and I’m very happy I was able to attend! Although I love my Hudson Valley corps, it was interesting to see how the New Hampshire corps works, and I might be able to meet up with them again at All Corps next month- the different SCA corps in the northeast (Masscorps, New Hampshire Corps, Adirondack Corps, and Hudson Valley Corps- I believe we are the only one that doesn’t live and work communally) meet up for community building and competition. Thank you to the Hudson Valley corps and the New Hampshire Corps for making our visit possible- we’ll be able to use this new information to safely move loads and create better improvements on our trails!

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6 thoughts on “Do You Even Hoist?

  1. Looks like you are learning some interesting things. How DO you decide if the equipment is strong enough for the job? In that last photo, it’s amazing that the line can hold the weight of that rock. Did you have to learn all kinds of fancy knots to keep things secure?

    • I just typed out a really long reply which my computer ate, but that’s okay because it was kind of rambly and didn’t make much sense. Basic points are:
      -each piece of gear (line, hoist, shackles, slings, blocks) has a working load limit (WLL) that’s 10-20% of its breaking point. So if a sling was only rated for 1500 lbs, we wouldn’t use it with a 2,000lb hoist, it probably wouldn’t break but it’s always better to err on the side of caution when thousand-pound rocks are involved. We did a lot of careful reading of the WLLs and calculating how much force would be on each part of the system.
      -the hoist itself had a cool safety feature: shear pins, that pop (without releasing the load) if there’s too much force on them. So the hoist was rated for 2,000lbs, but you could keep cranking after hitting that point, until the pins popped and the load stopped. It doesn’t all unravel and fall apart like a cartoon. You can’t continue to crank it in but you can slack the system and fix it or just give up on that rock (which we had to do once.)
      -we didn’t tie a single knot the whole training! The line is attached to the hoist’s mainline with a shackle (rated for like 4 tons of force) and the hoist is attached to an anchor tree with a shackle and sling. The blocks are also held up by shackled slings, and the load is slung and attached with a shackle. Shackles!
      Thanks for reading and questions, hope the answers sort of make sense!

  2. Pingback: All Corps- the Extended SCA Family! | Dorothy Ann Writes!

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