OT: counterbalanced stairs

I was so pleased with myself, I thought I had posted about this before but apparently not.

I wanted pulldown stairs in my garage for some light duty storage above. I hate the rickety spring loaded ones, and had vain hopes that having somewhat 'real' stairs would mean it would not always be me fetching stuff from above[hah]

I dislike spring action, as it would not do what i wanted without what I considered excessive complexity

SO it occurred to me that a properly placed counterweight should get me what I want: push up and stay up, pull down and stay down.
My first thought was mount the counterweight on a 45 degree up facing leg. When the stairs are down, the weight is over or ahead of the pivot and thus pushing down; steps up, it is working to keep them up.

Low pitch roof frustrated that. Only maybe 15 degrees available.

reinforced the rafters.
2]2x10 stringers, rabbeted on the radial arm saw[hah]
2]2x12x8 worth of steps
1]2x8x8 cut in half screwed and glued at the max angle available to avoid hitting the roof
Pivots on a 3/4 steel pin.

Built a plywood box hung on another pin to fill with concrete for the counterweight

Built a guard box hung from rafters under counterweight so that if anything failed that box of concrete would not fall on anyone's head

The thing that is amazing is how perfectly it works.

When down the stairs have perhaps a pound or two of downforce.

At knee height they are weightless[will balance motionless]

By head height they are moving upward

Then they fly upwards.

If they did not rub on the sistered rafters, due to sloppy workmanship, it would be perfect

I sometimes have to give them a nudge to overcome the friction to get them to sit up between the rafters and not interfere with the garage door.

A rope with a weight on the end sits almost on the floor less than a foot from the garage door, the garage door takes it up with it on the way up, but it is that long so it cannot fall in front of the door.

So I got through with this post and thought for sure I had a pic on my phone and don't so I will have to edit it later

Thought it might be of interest........
pic of bottom is it floating just off the ground.

With some pictures it would

Peter

My brother had a house built around 1943 with a counterweight garage door system. Wood box on a cable next to the door. Cable ran around some pulleys to pull up the door. He said it worked pretty well. He had to add a little weight in winter when the wooden door got heavier. It was filled with big rocks on the bottom with iron "stuff" on top. Occasionally he would pull something useful from the box and replace it with something of similar weight. It had pieces of pipe, bolts , nuts, etc.
This house was built during WW2 when materials were in short supply. There were probably no door springs made for four years. I bet the scrap iron came for the navy yard in town.
BIL LD

Bill D said:

My brother had a house built around 1943 with a counterweight garage door system. Wood box on a cable next to the door. Cable ran around some pulleys to pull up the door. He said it worked pretty well. He had to add a little weight in winter when the wooden door got heavier. It was filled with big rocks on the bottom with iron "stuff" on top. Occasionally he would pull something useful from the box and replace it with something of similar weight. It had pieces of pipe, bolts , nuts, etc.
This house was built during WW2 when materials were in short supply. There were probably no door springs made for four years. I bet the scrap iron came for the navy yard in town.
BIL LD

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I read a book about an early balloon pioneer and it had interesting facts about balloon ropes
They were large and heavy.

Think on the physics

AS the balloon drops it has 50 or 100 pounds of rope, as the balloon gets closer to the ground, the rope starts hitting the ground and no longer weighing the balloon down. It makes for graceful and safe landings with a questionable control mechanism[burner or air vent]

Wings of Madness: Alberto Santos-Dumont and the Invention of Flight by Paul Hoffman

Your design reminds me of railroad crossing gates upside down. With those big cast iron plates. I think all the wood and steel arms have been repalced with fiberglass around here. So thy must have tossed those heavy counterweights.
Bill D

I can't tell where the counterweight is positioned.....on most stairs I can imagine, there wouldn't be room.

GregSY said:

I can't tell where the counterweight is positioned.....on most stairs I can imagine, there wouldn't be room.

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It's about 4 feet past the pivot, and vertically maybe a foot or less higher than the pivot.
Where I thought it might be useful in a shop environment is if you have one story office or bathroom like I do, and you wanted semi regular access, this idea would work without losing the floor space of stairs.It is too big for a house, it would take up a whole hallway, and have a giant air leak into the attic.

Occurs to me in a shop with a tall ceiling you might be able to make it store almost vertical if you got your geometry right.

I think a counterbalance is always superior to springs when there is room. Ancient technology but still valid today.

Very nice . . . I have a stair case that leads to the upstairs attic space (read old truck part storage) of my shop at home. I never thought of pivoting the stairs.

But I didn’t like all my heat escaping up through the opening for the stairs either so I built a trap door and used a block and tackle affair and a 1940’s foot stomp starter as a weight. When the trap door is shut, you can go outside and see the starter 20 feet up in the rafters of the lean to. When the door is open, the starter is about 6-1/2 feet off the ground.

Scottl said:

I think a counterbalance is always superior to springs when there is room. Ancient technology but still valid today.

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But my engineer friends were like, 'but no, you can do it with springs'

I was thinking of garage door counterweight with chain. As the door goes up the chain starts hitting the floor. lightening the 'tension' as the door becomes horizontal and thus 'weightless'

Oh, and ever have a counterweight die? unless the mice start eating concrete, I should be good for a long time

Counterweights are plenty good, engineering-wise and function wise.

Then, in the old shop that was built in 1919, it had iron weights that were about 2" dia x 12" long hanging alongside each window, inside the wall. The windows went up and own nicely...but once in a while you'd hear a 'clunk' and you knew another weight had fallen down in the wall...the rope they used looked like cotton rope and eventually would fail. Keep in mind that was some 80-90 years after being put in. But, there was no easy way to retrieve the weights and re-hang them. The walls were all-wood slats that were staggered and laid horizontal, so to access the weight's vertical column, you had to remove about 40 boards then put them back the same place they came out. We did that a few times but that was only when we really needed the window to open.

I-pad enabled air solenoid....air cylinder up & down.

Make like star trek....swing.

yes, saah weights, used as ballast in many projects. I have never seen such poor castings. Bubbles, voids, flash etc. The tip i often spongy looking.

digger doug said:

I-pad enabled air solenoid....air cylinder up & down.

Make like star trek....swing.

Click to expand...

More like schwiiiing

wait, Wayne's World theme song coming up

GregSY said:

Counterweights are plenty good, engineering-wise and function wise.

Then, in the old shop that was built in 1919, it had iron weights that were about 2" dia x 12" long hanging alongside each window, inside the wall. The windows went up and own nicely...but once in a while you'd hear a 'clunk' and you knew another weight had fallen down in the wall...the rope they used looked like cotton rope and eventually would fail. Keep in mind that was some 80-90 years after being put in. But, there was no easy way to retrieve the weights and re-hang them. The walls were all-wood slats that were staggered and laid horizontal, so to access the weight's vertical column, you had to remove about 40 boards then put them back the same place they came out. We did that a few times but that was only when we really needed the window to open.

Click to expand...

If the windows were made properly there would be an opening at the side that had a removable piece. The piece was in the sash track. I did restoration work at one time in my life. Like needing over 100 BDFT of pine to trim a window.

Thas a big winda

At last, a project I can use my huge inventory of sash weights and disk brake rotors for...

gustafson said:

But my engineer friends were like, 'but no, you can do it with springs'

I was thinking of garage door counterweight with chain. As the door goes up the chain starts hitting the floor. lightening the 'tension' as the door becomes horizontal and thus 'weightless'

Click to expand...

And pretty much since the beginning ski lifts have been tensioned with counterweights that self-adjust as the cable length changes with temperature.

Scruffy887 said:

If the windows were made properly there would be an opening at the side that had a removable piece. The piece was in the sash track. I did restoration work at one time in my life. Like needing over 100 BDFT of pine to trim a window.

Click to expand...

My old windows had "hatches" that removed with one screw after the inside stops (also secured with screws) were removed to get at the sash.