Moving fireplace down flight of stairs

[Johnbailey]

I have decided to move a 450lb fireplace down 12 basement steps. I'm looking to design and build a simple winch and pulley to control it's descent. I have a boat trailer winch and some pulleys which will connect to a 4 wheel piano moving dolly. What I need to know is the weight the object the fireplace will develope as it changes from a horizontal plane to a 45 degree slope. Any help is greatly appreciated!

 

[MattRR]

Horizontal, you are pulling the coefficient of friction times 450 lbs, or about 150 lbs. At 45 degrees, to be safe, I would make sure you can handle the full 450 lbs.

 

[EnglishMuffin]

What you are asking for is the component of the weight in a direction 45 degrees to the horizontal, which is :

weight * sin 45 degrees = 450 * .707 = 318 lbf

Some years ago, I installed a Bridgeport milling machine in my basement, with the help of a local removal guy. The machine had to be completely disassembled, and the heaviest component was the column, which weighed about 700 lbs. This is a comparable exercise to what you are attempting. But one thing the removal guy insisted on was that the stairs had to be shored up with columns from below - this was based on bitter experience. Many stairs are very weakly nailed in position, so unless you are sure about that aspect, I would shore up the stairs first.

 

[arto]

See if the firebricks come out, then re-cement them in after ;-)