Hoisting pianos

[Ron Nossaman]

> Though 
> a block a tackle would work, Ron's suggestion of a differential hoist 
> seems much better in that it locks if you let go. Question about that 
> though is how do you change direction? 

It's a continuous chain. You pull on the other side to lower 
it. It's hard to even find a picture of one, but maybe this 
attached little gif will explain it. The problem with a 
differential hoist, other than finding one, is your chain 
length has to  total at least four times your lift distance. 
You need a big bucket to contain it and keep it off that 
marble floor. A regular geared chain hoist would work fine 
too. You'd have to come up with long enough lift and drive 
chains, but they wouldn't be underfoot on the floor during the 
lift, and you can let go without dropping the load. Ideally, a 
geared electric chain or cable hoist, hung at an appropriate 
height and controlled from the balcony by pushbutton, would be 
the slickest and easiest way to go. That is, again, if you can 
find one with an appropriate load rating.

I assume a chain, or more likely cable, will be hung from the 
overhead beam to about 10' above the glass wall, and the hoist 
hung from that. One nice thing about a geared chain hoist, 
electric or manual, is that the heavy sucker can be hauled up 
the ladder and hung on the cable naked, and the chains can be 
hauled up separately, and installed. Makes the process more 
survivable.

Ron N
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