This is my cable cam (Falcon Cam) I have been building. Basically a self levelling system. Using two ropes on top of each other for gravity driven applications. An additional endless rope loop is needed to manually- or power driven to make it travel back and forth. The lower rope can be hooked to a manual- or power driven drum to make the rig travel up and down. Using this setup I can have an X and Y travel.
I used aluminium for the frames. The bottom plate is a Mitchell plate for motion picture fluid or remote heads.

The rope is 1/4" Tech 12(Samson) or T-12 (New England Ropes) This one is coated black. There are a few other ropes of this caliber are available. ( I had these in stock.)

I have been searching for an inexpensive solution for a winch. I had a buddy suggest to take apart a golf car and build it into a mount througha drum. Not a bad idea. Back and forth and adjustable speed.

Also I am in talks with a company who might be able to help for a reasonable fee to design one.

I have worked with the FTSI winches on some of my jobs, but they are way too expensive for my personal projects.

I have been a rigging grip in the movie business for over 14 years. If any of you have a question feel free to contact me. I gladly share information I know or have experienced.

Here is a link to my website: http://www.bkp-rigging.com

Balint

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Nice rig! Two axis cable cams are great. I have a few suggestions for you;

#1 Remove about half of the metal on your skate/pulley system. Structural strength is not as important with your skate, the most that it will be lifting/flying is 200lbs. Less weight on the system the better. This will help decrease your maximum anchor pull when the weight of the rig is in the center of the line.

#2 I would consider a stronger rope to fly the rig. If you are flying over people, you are going to want an 8:1 working load vs the normal 5:1 working load

#3 You are going to need a motor with a lot of stall torque to raise and lower the camera,

#4 Check out electric vehicle sites, they have everything you need in regards to DC power, motors, and speed control

#5 i would tend to go away from too complex of a drive system, any chain, gear slop, directly transfers to the camera image, and in your case camera swing. The speed controller you use will greatly effect how the motor performs as well.

Cheers and good luck!

Thats a nice looking rig.
For the main drive rope, I used two dual groove pulleys. This allows you to maximise the amount of contact (grip) the rope has. This avoids rope slip when you accelerate quickly. I think I ended up having about 3/4 to 1 whole wrap of the drive pulley. (Depending on how I run my direction changing sheaves)
When I was reseaching drive systems I got some ideas from shipping and cable pulling 'friction drives'. I found a great article to do with theatre winch design which I put in the links thread. As it was a powerpoint document, which was a pain in the arse, DPC nicely converted it into a PDF. Here's the link he put up. http://www.dpcfilms.com/HowTo/Articles/CableCam/docs/USITT_2006_Winch_Session_com_lo.pdf
I will be posting some more photos soon of my newest drive system. Modified but as yet unpainted.

Dear Axl,

Thanks for your thoughts on my Rig.

The rope I am using is the actually 8mm (5/16"), not 1/4" as I stated. This twelve strand, single braid rope has a tensile strength of 13000# (not a mistake, thirteenthousand pounds) (The 6mm is 8150#). Made by New England Ropes (T-12). This is the same size Spidercam uses.

The trolley is 22#. It's not light but considering it's size: 43"x15.5". I could have cut out the middle to "lighten" it up but I felt at the time that it was not that important. I know every ounce counts.

The traveller is 25.6#. I used a 11" sheave to have a grand turn and to help better stabilize the rig. I might have to get a gyro to help the "swinging". If I ease it in down hill when I let go of the traveller, it stays stable and of course level.

My first job is going to be with a video camera with a Weaver Steadman head, so I am not worried about the weight. If and when I get a gig for a 35 mil shoot with a Libra head I will have to do some lightening of the rig. Cut out everything I can to loose weight.

Dear navillus,

The up and down travel (Y) can be assisted with a counter balance system, so the motor sees much less load. Plus the single sheave on the traveller gives a thearetical mechanical adventage of 2:1.

Do you have a picture of your cable cam and drive?

Thanks again for your input and thoughts.

In about two weeks I will be taping a test run with a buddy of mine. I should have some good shots.

Thanks,

Balint

Here is a picture of a descender rig from Spydercam on Spiderman 3 in New York.

I have some info about my cablecam in this thread.
http://www.cablecam.org/forum/viewtopic.php?f=1&t=53

My newest drive system is slightly different to the one in these photos. The frame with wheels is still used but the motor and drive pulleys are orientated differently. My method for directing the drive rope is different also.
I will get some photos of this soon also.

Navo,

Pretty slick. I assume you have full pan and tilt. Impressive.

Balint

This might help you out.

http://www.cablecam.org/forum/viewtopic.php?f=13&t=75