Engineering students, that is. We build things.

In this particular case, I built a crane to hoist an old swamp cooler down off the roof and then hoist the new cooler up.  Anna and I did the whole thing ourselves.

Warning!  Don’t try this at YOUR home!  Lifting large loads high over your head is dangerous.  You could kill someone, or smash a hole in your wall or roof, or drop and break something very expensive.  Possibly all three.

The crane, undergoing tests

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Old cooler ready for lowering

New cooler ready for raising

The operator at the winch

The cooler on its way up

New swamp cooler on the roof

In the back yard, there was a hand truck fastened to a ladder with hose clamps, braced against the side of the house.

On the ridge of the roof, I built a little platform with a winch on it, and tied the platform to our car (parked in the front yard) so the load wouldn’t drag the operator over the roof and into the back yard.

The operator cranks the winch, and the ladder lifts the load (safely strapped on to the hand truck) into the air.  The hand truck is placed such that when the ladder is cranked up against the roof, the load is just above the surface of the roof.

First we lowered the rusted-out cooler into the back yard, to test everything.  It worked fine, but the attachment point I chose put too much bending stress on the ladder.  After fixing that, we loaded the new cooler on the hand truck, strapped it down with a ratchet strap, and Anna started turning the crank.  It rose into the air like magic.

When it was about four feet in the air, it suddenly shifted.  The base of the ladder was no longer level.  I had Anna lower it to the ground again and did some leveling and chocking.  It seemed to do the trick.

Were I to do this again, I’d use guy wires to keep the ladder from tipping or twisting.  The wires would run from the top of the ladder to stakes pounded into the ground at the base of the house.  Or possibly to a couple of large friends.

I was extremely pleased with how well it worked, and relieved that we didn’t break anything.