# Ski lift christmas display



## BrianWolfe (Apr 16, 2013)

Here is one for the very clever. I have been asked to build an overhead ski lift for an animated Christmas display. 40' to 60' long continuous loop. It has to run reliably for at least 5 seasons.
How would you attach the ski lift chairs to the cable? How do they go past the pulleys on the ends?


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## Footer (Apr 16, 2013)

What is the scale of the chairs and lift?

Personally, I think you need to do some research. Gore is still open this weekend if you want to stay in NY, 3 hour drive from your shop. Otherwise, Killington is open today. 

I see no reason why you would not do this just like a regular full sized life. The way they operate is with a bull wheel on each end. 



The cable then rides over (and sometimes under) sheaves on each tower. It is imperative that each tower is perfectly square to each other because only gravity and tension keeps the cable on the sheaves. 



In the old days the haul "rope" was spilit open and the chair had teeth and went into the rope to hold the chair on. Now they all have a clamp that holds the cable. 



If this thing is full sized, odds are you will be able to buy used parts/chairs pretty easily. There is a pretty large used lift market out there.


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## cpf (Apr 16, 2013)

BrianWolfe said:


> Here is one for the very clever. I have been asked to build an overhead ski lift for an animated Christmas display. 40' to 60' long continuous loop. It has to run reliably for at least 5 seasons.
> How would you attach the ski lift chairs to the cable? How do they go past the pulleys on the ends?



Based on how real chair lifts work, the "outer lip"/inner depression on the drive wheel has to be large enough that, even as the cable rides up over the clamp it still can't leave the track. Annnnd too slow, Kyle has a much more comprehensive explanation - I too would recommend looking at going "full sized" as opposed to DIYing it from scratch, if only for the safety concerns...


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## BrianWolfe (Apr 16, 2013)

Full sized is not an option. The chairs will have 2' tall figures. Everything is scaled down. The producers would prefer the chairs be permanently attached to the cable in a continuous loop.
How does the connection to the cable work for both the horizontal pulleys at the ends and vertical pulleys in the middle without fouling one or the other?


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## emac (Apr 16, 2013)

The sheaves that the cable goes over/under are usually set on some sort of suspension. And the clamp that attaches the chair to the cable is tapered on either end. This combination means that as the chair goes over the sheaves there is noticeable bounce to the chair and noticeable give to them as well. Maybe YouTube some ski lifts in operation.   If you can wait till this weekend I can go take some close up shots of a small two seat ski lift. Its done operating for the season so I can get as close as I want. If you want any specific pictures let me know as well
Sent from my RM-820_nam_att_100 using Board Express


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## Chris15 (Apr 16, 2013)

emac said:


> The sheaves that the cable goes over/under are usually set on some sort of suspension.



One will note that in the second photo Footer posted earlier - the pivot points allow some movement up and down...


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## BrianWolfe (Apr 16, 2013)

Pictures would be great. Job installs in November but I need to price it soon.


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## Footer (Apr 16, 2013)

BrianWolfe said:


> Pictures would be great. Job installs in November but I need to price it soon.



I don't have a good shot of a bull wheel in action, but I have plenty of the lines over the chair. The big thing is you want to have as little as possible protruding from the inside and bottom of the haul rope. 

Once again, the biggest thing is everything has to be square. Also, sheaves on the towers really don't have much concave at all. The rope rides on top of the sheave, not inside. They have so little that in the right wind the rope can actually be blown off the sheave. Same thing goes for the bull wheel, there is no real deep concave that keeps the rope in place. Incredible tension and gravity keep the whole thing working. Also, usually the bottom station has some sort of sliding mechanism that keep the whole thing taught as the temperature changes. 



And some of my shots that I took this season: 













If you really want the detail (and after you get the gig) give a drive up to Hunter Mountain. Its not too far for ya... and they have a very good mountain manager who will probably get a kick out of this project. Also, if you want some local help throw a post up at Whiteface, Gore Mountain, Plattekill, Hickory Ski Center | NY Ski Blog. Also good people and close. Finally, there is skilifts.org. They have a ton of pictures of all types of lifts. 

Sounds like a really fun project.

Finally, keep in mind even at a small scale you will need some kind of braking mechanism for the whole thing. Otherwise, this happens: 


And here is the entire thing... it will make you never want to ride a chairlift again:


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## gafftaper (Apr 17, 2013)

Some good stuff in this article. 

Includes this picture of a design that uses a counterweight at the top to maintain tension on the system. Seems like a good solution for your purposes.


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## JohnHartman (Apr 17, 2013)

I believe Thunder Ridge should be rather close to you, its a small ski hill with a lift system that you can take a look at.

137 Birch Hill Rd
Patterson


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## BGW (Apr 19, 2013)

Keep in mind that you're going to want to look at an older lift, like the ones posted in this thread (most of which are ancient). You'll want to stick to a counterweighted system instead of modern hydraulic tensioning, and you'll most definitely want to stick with fixed grips. The Eskimo (lift in video) and the blacked painted lift that Footer posted pics of were made by Riblet. You should take a close look at them as Riblets are some of the simplest lifts and will be the easiest to copy. (Note: do NOT copy Riblet towers, stick with something more like Leitner-Poma's design) If you want to be accurate to the scale, you should aim for around 150 fpm line speed or less. Most fixed grip lifts are pushed to the maximum permissible speed of 500 fpm, but that would look absurd with a 1/3 scale lift of such short length. You should have a motor drive for soft starting so as not to strain your grips and chairs. 

Sorry for this jumble of thoughts. I'm in a bit of a hurry. Basically, I hope whoever is commissioning this has deep pockets, as it'll cost tens of thousands to do properly (read: SAFE and durable).


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