Electric Hoist Malfunction - What Would Happen?

[ddurrett896]

I have a Harbor Freight electric hoist I useto raise/lower a set of stairs to get to my attic. When not in use, the hoist keeps the stairs suspended in the ceiling.

What would happen if the hoist gears fails? Would it just unravel and fall? Thinking thru what I could do to prevent an accident if the hoist ever did fail.

**Pictures in post #31

440 lb. Electric Hoist with Remote Control

Amazing deals on this 440Lb Electric Hoist With Remote Control at Harbor Freight. Quality tools & low prices.

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[dogdog]

There was a psa thread here not too long ago. I think that guy/gal got injured pretty bad. It’s about 2 months ago.

*** that was his diy man lift not stairs lift

 

[DGersic]

I have a Harbor Freight electric winch I just to raise/lower a set of stairs to get to my attic. When not in use, the winch keeps the stairs suspended in the ceiling.

What would happen if the winch gears fails? Would it just unravel and fall? Thinking thru what I could do to prevent an accident if the winch ever did fail.

I would want a positive lock on any overhead contraption. Something that restrains it, and is visibly doing so.

 

[cvairwerks]

A winch is designed usually for a horizontal load. For vertical loads, you really want a hoist. Should yours fail, it will let the stairs down and at an unknown rate, depending on the failure mode. To prevent it from coming down, you need some kind of a cross lock that will support the stairs without the winch carrying the load.

 

[sjvicker]

Because you have a fixed load that only moves in one direction, have you considered a pulley and weight system? Doesn't seem like it would be too hard to figure out and dial in.

 

[jmdirk]

Good chance that the only thing keeping your stairs up is a mechanical brake on the winch.

I'd want some kind of mechanism to keep the stairs up that doesn't rely on the winch brake.

 

[tarmy]

Welp, first of all, is that a real overhead winch or an actual hoist?

A proper hoist has dogs or some type of device in addition to the electric brake and is designed for lifting the load. A winch is different.

 

[Firebrick43]

One shouldn’t trust their life to anything sold by harbor freight

 

[racecougar]

Yep, if/when that winch brake fails, it will drop the stairs at an unknown rate.

 

[Firebrick43]

The one @dogdog mention if I recall correctly the cable failed. The one I had also failed as a result of a bad crimp on the cable.

 

[ddurrett896]

A winch is designed usually for a horizontal load. For vertical loads, you really want a hoist. Should yours fail, it will let the stairs down and at an unknown rate, depending on the failure mode. To prevent it from coming down, you need some kind of a cross lock that will support the stairs without the winch carrying the load.

Just updated - it's actually a hoist I just called it a winch.

 

[ddurrett896]

Because you have a fixed load that only moves in one direction, have you considered a pulley and weight system? Doesn't seem like it would be too hard to figure out and dial in.

Tried that initially with a ton of pulleys and workout weights but was super temperamental and the $100 hoist was a no brainer.

 

[ddurrett896]

Welp, first of all, is that a real overhead winch or an actual hoist?

A proper hoist has dogs or some type of device in addition to the electric brake and is designed for lifting the load. A winch is different.

It's a hoist - see link below.

440 lb. Electric Hoist with Remote Control

Amazing deals on this 440Lb Electric Hoist With Remote Control at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

 

[dogdog]

It's a hoist - see link below.

440 lb. Electric Hoist with Remote Control

Amazing deals on this 440Lb Electric Hoist With Remote Control at Harbor Freight. Quality tools & low prices.

www.harborfreight.com

you would be fine if you are just lifting the stairs and not materials or person or standing under it while it lift or lower.

Otherwise make sure you read carefully about that 440Lb limits... I have the 880 and 1200 ones I think.. that is the max load rating and rating is using the ****** block for double the cable.... and those are static load I think. means not some one start bouncing at that thing while lifting...

 

[dogdog]

The one @dogdog mention if I recall correctly the cable failed. The one I had also failed as a result of a bad crimp on the cable.

I don't remember seeing any pictures on that thread, just from the posting

 

[dogdog]

One shouldn’t trust their life to anything sold by harbor freight

I wouldn't be trusting any hoist / winch as an personal elevator.

 

[racecougar]

you would be fine if you are just lifting the stairs and not materials or person or standing under it while it lift or lower.

I'd advise against relying on it to park/hold the stairs in the up position, especially if any person or item of value will pass beneath the hoisted staircase.

 

[RPH]

The hoist should have a deadman’s brake on it. Anytime the power is off the disc brake engages on the other end of the motor. Brake is only off when motor is powered. You should hear a clicking noise when power goes on / off. That should be the disc brake engaging and disengaged.

 

[dogdog]

I'd advise against relying on it to park/hold the stairs in the up position, especially if any person or item of value will pass beneath the hoisted staircase.

you can always over engineer it.

 

[racecougar]

It does have a brake; you can see it in the manual for the hoist. I'd still suggest another means of parking the staircase in the up position. Maybe I'm over-estimating the weight of the staircase, but then again, if it was difficult to hoist it manually, maybe I'm not.

The manual for the hoist even states that it shouldn't be used to park a load.

 

[racecougar]

you can always over engineer it.

I'd rather do that then see someone get injured or killed.

 

[AC-WC]

Can you put a simple brace/2X4 underneath it? Before I removed the old ceiling in my garage it had some VERY heavy stairs that were on hinges. It took 2 people to lift it up/down. It was secured with a pole placed horizontally underneath it located by 2 holes. Simple and effective.

 

[BillK]

How about a picture ? I have a simple idea that might work but cant say without seeing what you actually have.

 

[The Cobbler]

really, any lifting device should be treated with respect... and mechanically fastened when in a raised position when working around .

 

[Jswain]

Don't stand under a suspended load.

That rule was written in blood. If the stairs freewheeled down and hit you would it hurt? Kill?

Equipment fails, I've seen hoist lines rated for 12,500lbs fail lifting ~ 2500lbs (improper rigging) but people seem to think if I go ** over the safety rating it's fool proof... It's still equipment.

 

[walta]

The hoist should have a deadman’s brake on it. Anytime the power is off the disc brake engages on the other end of the motor. Brake is only off when motor is powered. You should hear a clicking noise when power goes on / off. That should be the disc brake engaging and disengaged.

I took one of the HF 440# hoists apart becouse the gears sounded like there were full of sand. I found no disk brake as far as I could tell the brake is the motors stator it seemed to be spring loaded into dogs.

As to the original question the risk of failure increces as the hoist is loaded closer to it rating. Lets say the stairs require 150# to lift and the hoist is rated at 220# becouse we are not using the pully. You are at 67% of capacty. If you doubbled the hoist rating with an upgrade the chance of falure at 1/3 of its rated load seems very unlikley.

Walta

 

[428PI]

I use that model to lift up a heavy swinging door on my lean to. I've only had switch failure and some moisture get to capacitor.

 

[walta]

You might consider adding a latch so that the stairs can’t drop unless the latch has been released from a safe location.

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Walta

 

[rlitman]

I took one of the HF 440# hoists apart becouse the gears sounded like there were full of sand. I found no disk brake as far as I could tell the brake is the motors stator it seemed to be spring loaded into dogs...

Good to know. I have a HF 440# hoist that locked up on me, and I've been meaning to take a look at it (though I'll likely never get to that, since I really prefer my pneumatic chain hoists). In my case I had lifted my 80 gallon compressor tank to my loft and was in the process of lowering it to the deck when it locked up with about 3" to go. I had a real Dr. Strangelove moment with it (and regret not stopping to get a hat, but I like my hats too much to damage them on the low roof...).

You might consider adding a latch so that the stairs can’t drop unless the latch has been released from a safe location...

If you go that route (and I like the idea), make it so that it cannot be released unless there's no pressure on it. Otherwise you could pull the latch and watch the stairs unexpectedly fall. So, lower the stairs onto the latch, so that you need to lift them to release it (same as how a lock works on a car lift).

 

[Gutman]

Agree with all regarding not relying on just the hoist.

I'm looking to do something similar to lift one end of the stairs/ladder? up to my mezzanine. The upper end is hinged, and I intend to drill a hole in the stair stringer/ladder rail near the bottom, with another hole in an adjoining joist, and then pinning ladder in the raised horizontal position, with a pin made from round bar, and a 1/4" flat bar bent to 90 degrees so when pinned, the stringer/rail rests on the flat bar.

I took one of the HF 440# hoists apart becouse the gears sounded like there were full of sand. I found no disk brake as far as I could tell the brake is the motors stator it seemed to be spring loaded into dogs.

Walta: Was there is any oil in the gear box? I'm curious to know if the gear box contains oil and whether orientation of the hoist matters, as I've got another application I'd like to use this hoist, however it'd best fit inverted.

 

[ddurrett896]

How about a picture ? I have a simple idea that might work but cant say without seeing what you actually have.

Here is a picture with it up and down.

 

[racecougar]

Thanks for posting those photos.

Maybe I'm over-estimating the weight of the staircase, but then again, if it was difficult to hoist it manually, maybe I'm not.

I wasn't over-estimating. I would seriously recommend NOT relying on the hoist to park that load in the up position. I'd install a hand rail, too.

 

[BillK]

Wow that is a serious load. I would hook up some type of positive latch like Walta showed but even heavier with maybe a pull chain down the wall to unlatch it.

 

[RPH]

I took one of the HF 440# hoists apart becouse the gears sounded like there were full of sand. I found no disk brake as far as I could tell the brake is the motors stator it seemed to be spring loaded into dogs.

As to the original question the risk of failure increces as the hoist is loaded closer to it rating. Lets say the stairs require 150# to lift and the hoist is rated at 220# becouse we are not using the pully. You are at 67% of capacty. If you doubbled the hoist rating with an upgrade the chance of falure at 1/3 of its rated load seems very unlikley.

Walta

Well here is the bom from hf. It clearly shows a brake drum and the op manual talks about inspecting it. Sure it wasn’t a winch?
I worked for shawbox as field technician. All hoists from them is load tested to 175% of capacity. That doesn’t mean you should load it that high but it is tested at level.

 

[AffableCurmudgeon]

Make a t-shape brace that you can move aside when bringing the stairs down. Once stairs are tucked back up, move the brace under them so that the brace is holding the load.

 

[AC-WC]

Can you put a simple brace/2X4 underneath it? Before I removed the old ceiling in my garage it had some VERY heavy stairs that were on hinges. It took 2 people to lift it up/down. It was secured with a pole placed horizontally underneath it located by 2 holes. Simple and effective.

Here's the concept-

 

[ddurrett896]

Make a t-shape brace that you can move aside when bringing the stairs down. Once stairs are tucked back up, move the brace under them so that the brace is holding the load.

I’m trying to see this in my head but can’t.

I’d like to be able to push up something that kicks it a 2x4 horizontal (blocking the lift) then can be pulled back down in a vertical position to allow the stairs to drop.

 

[AffableCurmudgeon]

I’m trying to see this in my head but can’t.

I’d like to be able to push up something that kicks it a 2x4 horizontal (blocking the lift) then can be pulled back down in a vertical position to allow the stairs to drop.

What I was saying is this: Let's say your celling height is 8 feet. You take a 7' 10.5" long 2x4. You take another 2x4 about 2' long and attach that horizontally to the top of the longer 2x4. Now you have a T with a total height of 8'.

Bring the stairs up. Slide the T under the unhinged (next to the wall) side of the stairs. The T is now supporting that end of the stairs.

To bring the stairs down, slide the T out from under the stairs' end, and lean the T against the wall. You should be able to lower the unhinged side.

 

[rlitman]

Wow that is a serious load...

I'd guess it's less than many garage doors. And for that matter, why isn't there a counterweight or some sort of balancing system here?

 

[BillK]

I'd guess it's less than many garage doors. And for that matter, why isn't there a counterweight or some sort of balancing system here?

But a garage door isn't going to come slamming down like that would. Also I cant see where the hoist is actually attached.