OT: calling MgoEngineers and MgoPhysicsNerds

Submitted by Rodriguesqe on October 14th, 2016 at 7:38 PM

I recently moved into a new place. Im on the 3rd floor and the stairs are a huge (small) bottleneck that I couldnt get almost any of my furniture through.

I think the cheapest solution somehow is for me to build a crane and hoist it to a rooftop deck. From there it will be easy to get the furniture into my unit.

One of my coworkers happens to be a wiz at DIY and also is an accomplished welder. He can build the crane no problem.  But our plan is to build a cran with a base that we will weigh down (theres no good place to mount the crane). We will attach an electric winch to the crane

My stuff isn't overly heavy, just too big for the bottleneck, probably all under 100 lbs.

My deck is approximately 40ft above ground. Assuming my coworker builds a crane that can handle the load, how much weight will I need to weigh down this crane? Is there a ratio? And does the height matter to the ratio?

Thanks in advance to the MgoUser that knows this stuff off the top of his head.. I'll post an ms paint doodle of the crane to give some idea.



October 14th, 2016 at 10:01 PM ^

Engineer (UM) and physicist (after UM) here: you COULD spend a lot of time and money with an elaborate construct to get your furniture/appliances up there, or you could carefully disassemble them, bring up the pieces, and reassemble. Easier to do with some things than others, but there is not a single piece that could not be treated this way if done properly.


October 14th, 2016 at 7:44 PM ^

if it works, it's proof.  If it doesn't work, it could potentially be hilarious and net you $10k on America's Funniest Videos.  And if it kills someone, it's evidence in a lawsuit.  


October 14th, 2016 at 7:59 PM ^

its a 3 unit house, the former occupant just moved out, i think she had smaller stuff. But I have no idea how they got the firdge up here, which is considerably bigger than some of the stuff that didnt make it in. Replacing my stuff is another option but probably not a cheaper option. I have a pretty nice couch and I'd have to either go love seat or Ikea, but even then I'd come out behind in cash.

My budge is 100$ for winch, 100$ for steel, 25$ for 2 rain barrels, 100$ for pizza / beer for aid, ???$ for damage to neighbors places.


October 14th, 2016 at 8:14 PM ^

Have you contacted a moving company at all? A good size moving company will have a lift available and employ riggers to move it in and out quickly. I would guess that it would cost less than you would spend building this. Most importantly, the company would be liable for any damage to neighbors property.

However, if you're stubborn like me I understand if you want to do this yourself. Can't wait for the video.

Honk if Ufer M…

October 14th, 2016 at 8:13 PM ^

:"Why do you need an electric wench for a 100lb load"

Come on man, that's like asking why homemakers needed electric washing machines! I mean, if you were a wench would YOU want to take a 100lb load? Jeez, man. I bet a lot of guys would see a use for an electric wench also, regardless of load production. The Electric Wench is going to sell like gangbusters! Thanks for the idea!


October 14th, 2016 at 7:45 PM ^

Check with a moving company to see if they have a man lift.  All your shit can be affixed to it and it can raise to up and over the deck.  All your stuff can be lowered down.  Won't be cheap you'll need a crew of probably 4 guys.



October 14th, 2016 at 8:18 PM ^


would probably be perfect.

But I actually bought the place and will be renting it when I move out. Getting stuff in and out will be a recurring issue. If I can make this a good, easy solution DYI would be preferable. My coworker and I are bothe pretty excited about this project.

Steve in PA

October 14th, 2016 at 8:54 PM ^

You're gonna have probably $100 to $150 into a Rube Goldberg solution that might work and may not fail causing injury or worse but you don't want to spend $225 for a piece of equipment made for exactly what you want to do safely and quickly?.  

I admire your spirit of adventure and wish I could watch.  


October 14th, 2016 at 11:46 PM ^

If you're lifting something 40 feet you're going to want to be able to lift it 50 feet. He's going to need a literal ton of steel.


If the price doesn't kill it then we move onto the task of how to stabilize essentially a 50 foot column that will be flying a 100lb kite.


And if they do manage to assemble this monstrosity they'll need a flatbed to actually transport this thing to the house.


It's at this point that we should discuss just making a trebuchet. If everything else goes wrong he'll at least have a cool trebuchet.


October 14th, 2016 at 8:01 PM ^

Structural engineer here.

Distance above the ground is irrelevant. You have to know the width of your crane base, and the exact reach of your crane beyond the front (window facing) foot of your crane base.

Weigh all of your shit.

Take the weight of the heaviest piece times the crane reach. Then divide that number by the width of your crane base. That result is the amount of weight you need on the rear feet of your crane base. It might be more than you think.

Lift very slowly to avoid adding an acceleration component to the load you're lifting and you might be a ok.

Sent from MGoBlog HD for iPhone & iPad


October 14th, 2016 at 8:06 PM ^

Awesome! I knew someone would show up.

There are limitations to the space, I probably can make the base no wider than 5 ft.

The plan is to get two rain barrels, that could top out at 900 lbs.

So if I understand your math,

cran reach = 4ft (guess)

heaviest piece = 100 lbs

base is  5 ft,

I should be good with 80 lbs?