# Trying to move a suspended prop in a long oval



## toozie21 (Aug 23, 2012)

First off, full disclosure, but this is for a Christmas display, but for the sake of the thread, let's say I am trying to move a large styrofoam ghost .... (to be fair, there is no reason it couldn't be used for Halloween and Christmas, so it might be both).

I live on a dead-end and want to put a large flying ghost up at the end of the street. The thought is to use one of the large sheets of styrofoam insulation, cut and paint it, and seal it. I was then going to have it hanging from a rope that would pull it along in an oval racetrack fashion.

What I was imagining was using a pair of trees as end-points, and the the rope would be angled so on the left it would be higher than the right (so as the ghost flies, it would fly to the ground when going left to right, and then go around the tree, and then fly into the air when going right to left. I am thinking the trees are about 20ft apart (I haven't picked the exact trees yet) and the pitch would be about 10ft or so.

What I am not sure of (and can't seem to find the right search terms for the forum for), is the best way to do this. I am imagining needing a couple of wheels extended from the trees (say two for each tree), that the rope would travel around (maybe bike wheels). One of the wheels would be hooked up to a motor and would be what pulls the rope around in the circle. I would need something to keep the rope tight against the driving wheel so there is no slippage (maybe something like a skateboard wheel on a tension spring).

The other thing I thought would be useful (mostly because of the slope I am looking for) is a counterweight 180 degrees away from the ghost. This would keep the weight slightly balanced and should help with slippage.

The theory seems OK, but a little too simple. The things I am concerned about are keeping tension on the rope so it doesn't slip (or fall off the wheel completely). How to attach the ghost to the rope so that attachment doesn't get in the way of the wheels. If sagging in the middle is going to be an issue.

So with all that out there, does this seem crazy? Is there a Halloween prop tutorial that does something similar? Any suggestions for how I am looking at this the wrong way?


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## RoxyBlue (Oct 6, 2008)

I believe what you're looking for is help with an axworthy ghost. That's the search term to use. Here's an example, and there are more here on the forum:

http://www.hauntforum.com/showthread.php?t=33516&highlight=flying+ghost

Hopefully folks who've had experience with this prop can help with your specific questions.


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## toozie21 (Aug 23, 2012)

I know _of_ the axworthy, but I thought that those just go forward/backwards (not a continuous loop), and would only be for very lightweight props. Not true?


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## Abunai (Oct 28, 2007)

The Axworthy ghost can go in a continuous loop, but it is "easier" to implement with lightweight props. 
I've never done one, myself, but I've talked to people who have. It's difficult to get right. 
It does sound like what you are trying to implement would need to be "Axworthy-like".


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## toozie21 (Aug 23, 2012)

Yeah, the little bit of reading I've done on them, it sounds like they can be finicky to get right. Might be the best bet though if that is what the crowd thinks.


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## Dead Things (Apr 4, 2009)

I have run an Axworthy for a number of years, and they are finicky as all get out, wind being the main nemesis, but they are certainly a crowd favourite! The trick is getting the guide wheels as in-line and level relative to each other as possible. Mine is a little different from others in that I have elevation changes so it is very important to line up all the guide wheels. I also use crab line, which is excellent, with minimal stretch and can support a fair amount of weight ( I have experimented with a number of lines and crab is by far the best). I also mainly use thule as opposed to cheese cloth, as it is light and airy and doesn't hold water, so the weight of the ghosts stays consistent. Here's a link to my vid if you're interested.


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## toozie21 (Aug 23, 2012)

I'll have to checkout that rope at the local Outdoor World, thanks for the tip. I think wind would be a major issue for me as it generally rolls down the street like a small wind tunnel and the styrofoam would act like a big sail on those days.


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## RoxyBlue (Oct 6, 2008)

Weight of your prop will also be an issue, as abunai mentioned. It's impressive how little weight it takes to cause a line to sag.


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## toozie21 (Aug 23, 2012)

Due to the weight and wind, I've been trying to think of how else to do it besides an axworthy system (though I may need to come back to that). Here are some recent thoughts I've had on this:

1 - For the pulley/drive system, I think we need something fatter than a bicycle rim, but still concave. Maybe something like a rim to a snowblower or riding lawn mower. That would allow for more surface area for the rope to sit into as well as a larger concave lip to help catch the rope and keep it centered (even with something hanging from the rope). There would be two of these rims on each tree and one of them would be directly drive by the motor.

2 - Of the 4 wheels I think I will need, I think one should be adjustable to add tension to the lines when needed (this will then negate the need for something to keep the rope pressed against the drive wheel for tension).

3 - Go with the crab line for its cost and outdoor ability. Plus, it should be pretty easy to find something that will allow me to connect two ends of the rope together to add more and complete the loop (I am thinking some sort of metal crimp on thing that when you overlap the rope will pinch them together).

4 - Still noodling over what I could spray on, or coat the inside of the wheel rims to add some grip for the rope without tearing the rope up (like would happen if I used sandpaper).

Just some current spitball thoughts....


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## Abunai (Oct 28, 2007)

These thoughts may already be used in some implementations of the Axworthy, but:

Perhaps the adjustable wheel mentioned in #2 above could be strongly spring loaded like the tensioner wheel used in a lot of serpentine belt systems for cars. It would automatically keep the line taut without having to continuously, manually adjust the tension. 

Maybe you could brush slip-latex into the inside of the wheel rims for grip.


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## RoxyBlue (Oct 6, 2008)

With respect to the pulley/drive system, take a look at what Doc Doom did here:

http://www.hauntforum.com/showthread.php?t=33820

He made his pulleys from plates (discussed a little later in that thread in response to someone's question), which resulted in a really nicely deep groove to hold his line.


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## Otaku (Dec 3, 2004)

Abunai said:


> Maybe you could brush slip-latex into the inside of the wheel rims for grip.


A couple of things come to mind - Plasti-Dip liquid rubber and the spray-on stuff that's used for sealing leaky rain gutters. The only downside I can see is that the cable may cut into any "soft" coating on the inside of the wheel/pulley. You could mitigate that by using a wide band instead of a thin cable to run through the pulleys. Has anyone ever tried using pallet strap material in place of a cable? That stuff is strong as heck.


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## fontgeek (Jul 24, 2006)

A couple of thoughts...
You might look at a motorcycle wheel rather than a bicycle wheel if you need a wider trough/channel to work with.
Maybe something like a BBQ rotisserie for the motor, they're made to go for many hours and also to take the potential heat issues. They also tend to offer some speed variations too. And they're already setup to plug into an outlet and run on house current.
For the traction issue, how about using the adhesive backed "no-slip" material made for wet stairways and such?
You could put a wire or dowel coming out of the bottom of the skull to act as ballast, and anchor the cheesecloth or material to.


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## toozie21 (Aug 23, 2012)

Thanks guys, I appreciate the ideas and conversation. 

That is pretty ingenious with the plates. A good idea, but probably not strong enough for my application. The tension spring he has in place is pretty awesome though, i like that!

The plastidip stuff is a good idea, fairly inexpensive, and should have decent grip. If I go with a rope (over a thin line), I wouldn't think it would cut in as much (though it may wear it down into a groove every year (minor issue if I can make it through a season).

I was kicking around lawnmower and/or snowthrower rims as they would have more surface area in the concave section, and I was hoping I could pick some up inexpensive from a repair shop (they don't need tires and don't really need to match).


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