Cable Car

My grandma has trouble walking these days and I was going to build her a ramp. After examining code requirements, etc, I realized that a full sized ramp would take up a lot of space and be very expensive. I had to figure something out that would help grandma and my wallet at the same time.
So, after mulling about a few configurations and set-ups for a feasible ramp, I had a brain storm. Why not build an elevator? Further exploration of that idea exposed a few safety issues that I simply could not resolve to any degree of comfort or assurance of grandma's safety.
But, the seed was planted. I could not get the idea of a powered lift for grandma out of my mind.
This is where those musings led.

Step 1: Making the Plans

The first thing I had to do was determine where to put it and the needs of grandma to design it's function. First, it had to eliminate any steps between the house and the garage where the car is parked. Second it had to fit her small 35" motorized chair. And finally, it had to support her weight combined with the weight of her chair, or a cummulative rough 300 pounds.
Previously, there had been a short ramp in place for her to walk down. But, now the slope was too steep for her to walk down and her cart could not manage that degree of slope safely. But it's location was relative to the spot where a different ramp would work well.
Off her back porch I had built a 10' x 13' deck some 3 years ago.I decided to build the cable car adjacent and parallel to that deck so that she could simply roll out off the porch, across a few feet of deck and onto the car platform. I decided to build the platform to rise level with the deck at the top of it's rise and settle flush with ground level at the bottom.
So, I began by digging out the area next to the deck. Then I marked the locations for a few footers to build posts up to hold the rails.

Step 2: Placing the Footers

The idea was to roll a platform down two rails. So, I had to install eight footers to a depth of only 12 to 18 inches on which I would install short posts on which the rails would rest.

Step 3: Laying the Base

As you can see, the base drops about 18" below bround level. This will allow the platform to rest flush with the gound level at the bottom of it's run. But, I couldn't just leave it as a muddy pit below.
So, I layed in a layer of wire mesh on the ground surface, then pured in a 2" layer of concrete as a base. I installed a drain at the far end to keep it from filling with water. Then I cased it in with brick.
The drain was extended out from the base about two feet to link up with a french drain which I am now digging across the back yard to keep the rain out of the basement.

Step 4: Posts and Rails

The idea was that the platform will roll up and down a pair of parralel rails. So, once the concrete set, I cut posts from PT 4"x4"'s and using lag screws I attached the rails at about a 20 degree angle. The rails are cut from PT 2"x6" and run a bit over eight feet long.
I screwed the rails in line with the inside line of the posts so that there is a 2" over hang on the outside permitting the lower rear wheels two ride past them on the bottom of the rail. These are shown in the next step.

Step 5: The Platform

Now that the base and rails were installed, it was time to begin construction of the platform.
Essentially, it is a simple 40"x40" platform angled and set on wheels. I used PT 2"x10" to form two cantilevers on the outside of each rail and then tied them together with PT 2"x4"s and used deck hardware for added strength.
The front wheels I salvaged from my son's now defunct Hinda Minimoto motorcycle. They are 10" wheels with inclusive bearings. These became very important from a safety standpoint which I will explain in my next step.
On the rear of the platform, I used two sets of smaller wheels on each cantilever. Like a roller coaster, I positioned a small wheel on the top and the bottom of each rail to grab the rail and keep it from flipping forward.

Step 6: Safety!

Now the whole purpose of this project is to make grandma's life easier while at the same time feeding my need for eccentric efforts.
The idea of a little old lady careening uncontrolled down an eight foot ramp because the cable snapped was simply a stopper to this project until I could figure out a way to pre-empt such a disaster.
This is where those Minimoto wheels come into play. I thought they had been thrown away with the rest of the bike after I took out the electric motor last summer. While searching for something else, I found them , much to my suprise, stuck up on a shelf in the garage next to an old Ford 5-speed transmission from my old Escort.
On the rear wheel of the motorcycle was a drum brake! How absolutely incredibly lucky was that! The project could proceed.
I loaded the brake with a spring on one side which locked the brake. Then from the other side of the brake, I ran a cable to the main cable. So, if the main cable snaps, the spring will automatically retract and lock the brake

Step 7: Power

I bought an electric hoist motor with a 450 pound strength to use to operate the car. It's only 110 volt with a max draw of 20 amps.
From the basement, I ran a power line from a dedicated breaker and used water-proof conduit and junction boxes. this step was probably the easiest.
I mounted the motor below the rails inside the rear-most posts. Then I used 485 pound test pulleys to run the cables to the platform. All the hardware holding the motor, pulleys and cables is stainless. Nothing is too good for Grandma!

Step 8: Completeing the Platform

Once the motor was installed, I test-ran the whole works. The platform rolls smoothly up and down the rails, each run taking approximately 30 seconds, for a full one minute circuit.
I've tried to load a video of my test run, but can't quite figure out how. I've posted a question about that in the Help section and will include it in a re-edit once I've figured it out.
Finally, I laid on decking as a walking surface and installed a light-weight railing.
At the bottom of the run, I poured a concrete pad which matches up flush with the platform at the bottom of the run. Grandma can roll out onto the deck and right across on to the platform at the top. Then an easy decline down to ground level where she can roll right out onto the sidewalk and then to where ever she'd like to go from there.
The only issue I still haveto figure out is how to put the control on the platform itself. The control wire is only five feet and I need it to extend about nine feet to followthe platform. But at the same time it needs to neither drag on the ground nor be run over by the platform itself without being lifted overhead. If anyone has any thoughts an that matter, I'd be happy to hear them.

Thanks for reading everybody!

Comments

[muddog15]

Great for moving furniture. Time to make a big version of this.

[Tinworm]

Rather than a cable car, I think this is a funicular railway, in essence, isn't it?

I really like it. It is a very nice project, very nicely built.

From the positioning of the black railing, I presume Gran's wheelchair goes straight in (so that she will be facing uphill). But doesn't this make rolling off on to the deck at the top tricky (having to turn her wheelchair left before exiting)? I think I'd have had her rolling on to it from the right, so that she faced the deck, then roll off straight ahead at the top (and reverse when coming down).

[sfarmer11]

What if you put your line like a loop so as it goes down all the loops extend but as its going up the loops gather collecting it nicely. Kinda like the cords and hoses on those big car trailers

[Roy Glen Gilliam]

You said, "I don't want to build a ramp", but on the front of your cable car is a ramp; don't know why you made both???

[Mockfish]

Thanks for the feedback everybody! I'm glad everyone likes it. Second to grandma, it makes it worth all the effort. I'll try to respond to a few of your thoughts here. I was actually considering the self-retracting extension cord adaptation for the controls. Good to know someone else sees the same thing I do. I think I'll go that way. Harbor Freight does have some inexpensive models. All the parts are gauged by working strength. So the weight limit is the weight limit. I made sure of all that before-hand. And I went with wood for cost. I've discovered in some of my other projects that wood has an amazing amount strength, so I'm not worried about breakage. Warpage I do think about, but I figure if necessary, it wouldn't be hard to simply replace a wooden rail versus the cost and effort with working with steel. And lastly, I did actually look at scissor lifts like for a motorcycle, but in the end it would have been more costly. It did have certain advantages such as a smaller footprint and a built-in inherent safety, but this design offers easier repair and upkeep. I mean if the jack broke, I'd need a whole new jack. On this, I could replace any part in a few hours at most. Thanks again everybody! Have a good day!

[Mockfish]

I still haven't got a video to post here since Yahoo video is not a supported source? But here's a link to a short one minute video of the test run. I shot this before the job was complete so the platform is still skeletal. Enjoy.

http://video.yahoo.com/watch/2838596/8207592

[greatscotmagic]

Great idea. I have to use a handicapped cart myself and I am looking to add a way to get from my porch to the gorund. This seems like it would really fit the bill. FYI, why not try putting the vidoe on Youtube instead of Google Video? Youtube is supported here. If you need help doing that, I will be happy to assist you.

[astro boy]

or post a link in the Instructable.

[RetroPlayer]

Regarding the retractable cable reel, I would worry about one thing. The clutches on these usually suck, especially if you get a cheap one. Also, they are usually designed to lock as you pull out the cable.

You might want to attempt make your own unless you can find a good one and figure out how to modify it to remove the ratchet mechanism.

Another option is to make it wireless and operated by a remote on a keychain. This also solves the problem of people using it when they shouldn't (wouldn't that suck if someone lowered it and then left it down?)

This looks perfect for your needs:
http://www.allelectronics.com/make-a-store/item/RC-12/2-POLE-REVERSIBLE-REMOTE-CONTROL/1.html

One question, though: How do you plan to stop the wench once it reaches its final position? Keep in mind that if the wench isn't stopped right away when it reaches the top, the stress will eventually pull your contraption apart, or at least damage the motor.

[Squid Tamer]

I think that mounting the motor on the car itself is the best option. I don't think that the cart would ever run over the cord as long as it dropped onto the side. And I can't imagine a little sliding every once in a while messing up the cables.

[heathbar64]

Beautiful job on this. ramps are always a pain because they have to be so long and are ugly no matter what you do. I may use this idea next time. I like the suggestion of a garage door opener. I think you would have to use the door springs as well to pull the weight. You didn't seem to use any rollers sideways to keep the platform centered on the track. Does it work smoothly without rubbing?

[Stinklove]

you could install metal strips to the sides of the rail and have metal brushes slide along them to transfer the signal to move.. obviously reverse the signal for moving in the opposite direction

[crazyrog17]

make sure it's a low voltage control circuit though or else there'll be fried cat lying around. have three strips, the center positive and the other two connected to the positive input of solenoids. when two are connected, that solenoid will circuit winding up and vice versa.

[rybitski]

Why not something like they use on large cnc's? : http://www.igus.com/echain.asp

Just mount it in the center of the track shere there would be no interference. I am sure you could make something similar for less.
Spectacular job by the way, very inventive! The safety brake is ingenious.

[Greenehouse]

Wow, fantastic idea. Well thought out and executed. The pictures and descriptions were right on the mark. Thanks for a great job. It has inspired me to work on something I have been thinking about for awhile (a Star Trek kind of elevator that is just a pole with a round platform you stand on.) I'm considering this for a quick way to get to the attic.

[Derin]

Weren't turbolifts like conventional elevators?Or are you talking about the elevator near the reactor?

[labrmnus]

Nice. My folks live on steep hill above a lake, they wish they had a cablecar. I wonder about a conveyor-belt, maybe made from those hand-cranked-fabric-truckbed-liner they sell to let you unload a load of gravel from truck. Or maybe have an swing-arm based device, somehow rigged to the platform stays horizontal as the arm itself goes through 90 degrees. Or maybe have cheapo pneumatic riser somehow, maybe made out of office chair chamber that deflates on command, or how about those screw-type car jacks with 2 jacks on each end tied to a central rotating motor moving both. Elevating devices can be neat but sudden drops can hurt, so I am cautious. Any comments on these things?

[thb43]

Here is an idea for your control wires. Look inside of an ink jet printer. There is usually a flat plastic ribbon cable connected to the print head. The flat cable rolls out/up when the printer head moves back and fourth. Do something similar for your cable car. Another idea is to put the motor on the car itself and make a sort of cog railway instead of using cables. Good job.

[Mockfish]

Wow, thanks for all the great input. And I thought I had thought of everything! But, let me answer some more of your questions. I've looked at a few self-retracting cords and some of them have a locking mechanism and some don't. I could probably recreate something similar, but if I can find a ready to use unit, that is the way I'll probably go. I tried a couple of spring setup already, but a spring that doesn't stretch itself out after a few runs tends to take a bit of the load off the cable and introduces a bit of slack into the cable causing a jerky and possibly dangerous ride. As far as keeping the cart on the track, the sides of the platform, what I called Cart-i-levers, extend down past the outside edges of the rails fully encompassing them. Then the cart-i-levers are tied together at six places inbetween them holding them securly together. I physically tried to break them apart and derail the thing and couldn't do it. I am confident that it is safe from that perspective. Didn't I post a front view of the installed cart in my instructable? It would show how the cart fits onto the rails. I'll check and if not, I'll add one in there. I did consider a key-fob style remote system, but along with Grandma's knees, her memory is slipping a bit as well. I think a fixed control would be less likely to be lost. She agreed. I set up the cable length to run out at the bottom so that the platform stops at it's maximum length automatically. At the top I left in about 8" of over run. So, if she passes the deck by an inch or two, she can simply stop and bump it back down to level. If this becomes a problem, I'll install some automatic disconnect switches at the top of the run. That won't be difficult and I may do it anyway. I've tried to use simplicty as a hallmark and don't want to add any more bells or whistles then absolutley required. Eye Poker has already spied out my next step. The railing on top of the deck will be replaced this weekend. The space below the deck will be blocked up with some of that wooden lattice when I build the roof on the deck later this summer. All in good time. I still have to dig the french drain across the yard first because I keep getting water in my basement when it rains. That must come first. Did I mention that Grandma and Grandpa live with my wife and I? They live on the first floor of the house and we use the second and third. And the basement is full of my fishtanks. But your concern for little fingers is quite justified since we've got three kids, so their safely has been a prime factor in all my works. Thanks for looking out for them though. Thanks again everybody. I'm glad you liked my project!

[pyro_fan_ryan]

u should make an onboard switch systm wit a swich fo up and u swich fo doun