Attic hoist / elevator design

[Molynoox]

This looks hugely over complicated. If you need a hoist, which may only serve to encourage you to store far too much "stuff", a simple electric hoist above a suitable hole with the rope or cable steadied by human hand as it rises should be enough. Worked well enough for centuries for unloading carts and riverboats. It's not going to be windy, and gravity plays it's part in keeping the load below the hoist. Maybe the reason there is no off the shelf solution is that there is no need for one.

It's not for me, it's a retired couple and they don't want to be carrying boxes up ladders, or steering platforms into little holes in the ceiling. I think they will be looking for maximum safety and convenience, whereas us workshop types might be happy just using a cargo net hooked up to an electric hoist.

 

[ChaiLatte]

I also saw on website that somebody asked of you can fit a bolt head in channel and apparently not

People lack imagination.

Find yourself a copy of the full Unistrut catalogue and peruse it. Download the drawings and CAD models of the parts and fit them together virtually. You will then see what is possible. There are lots of options.

On this page, linked to above:

https://www.unistrut.co.uk/search?keyword=trolley

P1834 would secure the strut to the wall with two small lines of weld between it and the channel.

You could dispense with the weld and put a packer between the item and the back of the strut channel. The cross bolt squeezes it onto the channel so the packer would need clearance around that and around the bolt securing P1834 to the wall (and be inseted after that bolt was done up).

If you look at P2949, so long as the bolt head was no greater in across-the-flats measurement than the inside measurement between the two wheels (there is a blurry diagram in your link - find a better one and work out that dimension), the wheels would pass either side of the bolt. You would have to tighten all the bolts to the same clock position.

Edit:

Have a look at: https://www.ebay.co.uk/itm/116230926422

These are UK made and are well priced (see the set of 4 for less than £70). You could ask the seller if it were possible to supply with a larger OD bearing, which would help with both the back-and-front nature of the contact between bearing and channel and also provide greater 'ground clearance' at the back to a allow a deeper bolt head if required. Failing the larger bearing, a steel ring/tyre on the bearing would increase its OD.

See also: https://snapklik.com/en-gb/product/...or-taller-strut-channel-design4/0IIC4P87AX2W5

 

[Jacob]

It's not for me, it's a retired couple and they don't want to be carrying boxes up ladders, or steering platforms into little holes in the ceiling. I think they will be looking for maximum safety and convenience, whereas us workshop types might be happy just using a cargo net hooked up to an electric hoist.

In that case I'd just go for an off-the-peg domestic lift. £2k to 3k

 

[toolsntat]

It's not for me, it's a retired couple and they don't want to be carrying boxes up ladders

In your own property what you propose seems all well and good but making and fitting something like this, possibly without any certification, to a clients property sounds like a court case waiting to happen.
Cheers, Andy

 

[ChaiLatte]

When Edison was asking on his inventor's forum about that little glass thing with wire inside it, I bet there were a load of people saying, "why not use a kerosene lamp like everyone else" or "you know you will be sued if you put that dangerous contraption in someone else's house"...

You might be aware that you are not the first person to have had this idea. If you search 'unistrut vertical hoist', lots of ideas come up.

https://www.advrider.com/f/threads/three-legged-storage-lift.1430143/

https://jayscustomcreations.com/2021/01/diy-elevator/

The other 'real world' item close to what you want is a food lift (dumb waiter), used in a restaurant where the dining area is not on the same level as the kitchen. If a used version of that were available, it might strike the right balance between economy and a proven safe design.

 

[Molynoox]

People lack imagination.

Find yourself a copy of the full Unistrut catalogue and peruse it. Download the drawings and CAD models of the parts and fit them together virtually. You will then see what is possible. There are lots of options.

On this page, linked to above:

https://www.unistrut.co.uk/search?keyword=trolley

P1834 would secure the strut to the wall with two small lines of weld between it and the channel.

You could dispense with the weld and put a packer between the item and the back of the strut channel. The cross bolt squeezes it onto the channel so the packer would need clearance around that and around the bolt securing P1834 to the wall (and be inseted after that bolt was done up).

If you look at P2949, so long as the bolt head was no greater in across-the-flats measurement than the inside measurement between the two wheels (there is a blurry diagram in your link - find a better one and work out that dimension), the wheels would pass either side of the bolt. You would have to tighten all the bolts to the same clock position.

Edit:

Have a look at: https://www.ebay.co.uk/itm/116230926422

These are UK made and are well priced (see the set of 4 for less than £70). You could ask the seller if it were possible to supply with a larger OD bearing, which would help with both the back-and-front nature of the contact between bearing and channel and also provide greater 'ground clearance' at the back to a allow a deeper bolt head if required. Failing the larger bearing, a steel ring/tyre on the bearing would increase its OD.

See also: https://snapklik.com/en-gb/product/...or-taller-strut-channel-design4/0IIC4P87AX2W5

I dont think there is enough clearance for a bolt
I like your idea of welding that little shoe onto the back of the channel best, thanks

 

[Molynoox]

Edit:

Have a look at: https://www.ebay.co.uk/itm/116230926422

These are UK made and are well priced (see the set of 4 for less than £70). You could ask the seller if it were possible to supply with a larger OD bearing, which would help with both the back-and-front nature of the contact between bearing and channel and also provide greater 'ground clearance' at the back to a allow a deeper bolt head if required. Failing the larger bearing, a steel ring/tyre on the bearing would increase its OD.

See also: https://snapklik.com/en-gb/product/...or-taller-strut-channel-design4/0IIC4P87AX2W5

yeah those look good thanks. The only issue I can see is that the clearance at the back (that would allow me to bolt it to wall) might cause issues with my other needed function to roll on back face of channel (as well as front) - I like your idea to contact seller and ask about larger wheels, which would solve that issue as long as there is enough clearance in the gap between the rollers to fit a bolt head.

 

[Molynoox]

In that case I'd just go for an off-the-peg domestic lift. £2k to 3k

I have only 550mm, and its not adjacent to wall, so I think it needs to be bespoke

 

[Molynoox]

When Edison was asking on his inventor's forum about that little glass thing with wire inside it, I bet there were a load of people saying, "why not use a kerosene lamp like everyone else" or "you know you will be sued if you put that dangerous contraption in someone else's house"...

You might be aware that you are not the first person to have had this idea. If you search 'unistrut vertical hoist', lots of ideas come up.

https://www.advrider.com/f/threads/three-legged-storage-lift.1430143/

https://jayscustomcreations.com/2021/01/diy-elevator/

The other 'real world' item close to what you want is a food lift (dumb waiter), used in a restaurant where the dining area is not on the same level as the kitchen. If a used version of that were available, it might strike the right balance between economy and a proven safe design.

yeah I've had a look on YouTube and Ive taken inspiration from a few
I did think about dumb waiters and I think they all work with a permananent lift shaft, which doesn't work in my application as cars will be parked below.

I probably need some flip stops or something that can be used as safety backups when hoist is not in operation
I could also look at some sort of centrifugal brake too? Im sure something off the shelf is available, maybe from climbing gear.

 

[Molynoox]

Bearing in mind if you are going to use a hoist then you are just talking about guides, you could just use two lengths of say 30mm tube, and cupped wheels on your platform. Look at something like a roller coaster, this is how the cars are held on. You could just use short pieces of tube that fit over the smaller long tubes, but if your lift isn't even they will jam. Cupped rollers that hug the tube, ideally both above and below the platform, won't.

thats a good shout
Ive been reading about the design of the trolleys, they use 3 wheels:

its possible they don't need to be cupped

part of me thinks this is the best direction, part of me thinks its over engineering and I should stick with the u channel...

 

[Fergie 307]

The advantage of cupped wheels is that you would only need two, ideally one in front and one behind above and below your platform. In fact for the relatively low weight you could just use one in front below the platform and one behind above it, I'm assuming two uprights and the platform being essentially like a shelf mounted to the uprights on the rear. This way the wheels are both pressed onto the tube by the weight of the load. The cupped shape centres them. You would need a solid strap around the non bearing side of each one with a small clearance to the tube, just to prevent them jumping off if anything were to go awry.
And don't forget to include the weight of the unloaded platform.

 

[Fergie 307]

thats a good shout
Ive been reading about the design of the trolleys, they use 3 wheels:
View attachment 186313

its possible they don't need to be cupped

part of me thinks this is the best direction, part of me thinks its over engineering and I should stick with the u channel...

Solid mounted with cupped wheels would not be a reliable way of holding the car on a roller coaster, they would also wear very much more quickly at the sort of speeds these things travel, hence the three flat wheels. And of course they have to deal with substantial lateral forces, not an issue for your lift. Cupped ones would be ideal for what you are doing, and I would guess probably the cheapest solution to the problem you have set yourself.

 

[pud1771]

I deal with this sort of thing for a living have a look on Google for a geda wire rope hoist. The motor is mounted at the bottom and the wore runs up and over pulley at the top. The wheels of the trolley run inside of the squared C Chanel that make the uprights the uprights are in 2 meter sections. I know who I work for are sending a fair bit of kit to auction at the moment so might even be a set up for sale at one of them

 

[Fergie 307]

This looks hugely over complicated. If you need a hoist, which may only serve to encourage you to store far too much "stuff", a simple electric hoist above a suitable hole with the rope or cable steadied by human hand as it rises should be enough. Worked well enough for centuries for unloading carts and riverboats. It's not going to be windy, and gravity plays it's part in keeping the load below the hoist. Maybe the reason there is no off the shelf solution is that there is no need for one.

A really simple way would be just to have two cables and eye bolts attached to the platform with the cables running through them, just to keep it centred in the hole. For light loads this ought to be fine, and is probably the very simplest solution. Just depends how rigid you need it to be. If the objective is just to stop the load twisting about and banging into the sides of the hole then this would do it, and very cheap. You would probably want to use the type of eye bolts that have liners so there is no metal to metal contact with the cable. Or simple enough to make your own with something like acetal as a bush in a tube.

 

[imageel]

As has already been mentioned, I'd steer well clear of anything designed or fabricated by yourself, the public liability risk to yourself is huge as you become responsible for the safety of your clients.
I'd certainly double check what public liability cover you have before considering this project.
Alternatively I am sure you can find a commercial solution which undoubtedly will not be cheap - but that in part is because the manufacturer has had to design, test and quite likely get approvals to sell equipment that has potentially life threatening consequences if overloaded or mis-used.
It's a completely different matter if this was for your own personal use.

 

[MarkAW]

In this case you would probably be considered both manufacturer and installer. You've a lot of obligations: https://www.gov.uk/government/publi...ons-2016/lifts-regulations-2016-great-britain

A quick Google yeilded that. I've no idea if it's current or the only regulation you'd have to comply with

 

[quintain]

Regretably no answers from me; only caution.

Make sure you design an emergency action auto braking system.
Such is mentionned in your post "I could also look at some sort of centrifugal brake too? Im sure something off the shelf is available, maybe from climbing gear."
I congratulate you and others on your consideratons and wish you the best with the project but please design into it something similar to a commercial lift that upon the cable snapping the lift cabin will only fall by a small distance and not plummet to the floor.
Irrespective of design and or good components it must always be realised that "if it can break" it will do so at the most inconvenient time; perhaps when some one is directly underneath it.

Please keep us all informed of your designs and considerations.

 

[Jake]

Also consider crushing risks for trapped body parts.

 

[Blackswanwood]

Could you base it on one of these?

https://liftingequipmentstore.com/c...weight-aluminium-hand-stacker-truck-wide-legs

 

[XTiffy]

In my barn I have a mezanine floor which I use for storage and I installed a 6 mtr. scaffold pole fixed at bottom and to the steel frame at the top. I bought one of the cranes that you mentioned in the original post, which has a scaffold clamp for attatching. I then modified a "Bulk builders bag" by putting a timber floor within (to keep the sides out) and then made a yoke to attach to the handle with a shackle at the centre, the yoke prevents the sides pressing on the contents when lifting. Only downside is that it is better with two persons, one to load and the other "up top" to operate/swing the bag inboard and unload. Otherwise a lot of up and down the ladder. I have seen many YouTube videos of much more advances lifts using these winches with safety stops etc. For my occasional use mine works just fine.