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Discussion Starter · #1 · (Edited)
I am trying to build a train like the ones that you see in the mall after finding out they want $40,000 to buy one. I have a complete workshop and can build pretty much anything, but I have little experience with large electric motors so I am not terribly sure where to start. I have read lots of tutorials on making these types of trains but almost everyone uses a repurposed lawn tractor. So it's good information for an overall build but I really don't want to use a gas engine for it because of annoying noise and it will limit my ability to use it inside.
Is there a good overall tutorial on the motors themselves to determine power to weight ratios, power usage and other things like that? I figure it's basically like building a small car except it would weight about 10k pounds loaded but only need to go approx 5mph. My only initial guess would be to buy an electric forklift and tear it apart but I want to find out other options first.

Any help is greatly appreciated. Thanks
 

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Hi
Your instincts are correct - an electric forklift would be an excellent first step
Although an electric pallet truck - the sort of thing an airport uses to shift baggage would be even better

Will you have to move this around the place? - or will it stay in one place?
 

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Discussion Starter · #4 ·
it's not going to stay in one location but I will simply load it onto a trailer to move it from place to place. Can you tell me what the difference between the forklift and pallet jack is? Is it just that the pallet jack is meant to go slower to start with or is there more to it then that?
 

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Hi
A forklift has its mast and hydraulics - sell those! - around here the farmers put them on the back of their tractors

Once you take those off you will have a good starter for your train
The only problem is that the rest of the structure is built like the proverbial - and is going to be heavy!
Even without the weights (sell them) It is going to be heavy - the pallet truck will not be a lightweight but it will be lighter
How much weight can you take on your trailer?
 

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Discussion Starter · #6 ·
im going to buy the trailer after the fact once I determine the overall size of the train so it will take whatever weight it ends up needing to. It will be fairly large as the train will be the better part of 40' but I will be able to put two rows of the cars onto the trailer so it will only need to be about 20' or so. A quick look on my local craigslist shows that I can get an electric fork lift for about 1000-1500 and a pallet jack type model for $500. What are things I should be looking for in my application? It would seem the pallet jack's have a lot more low-end torque but I'm not sure if that would be better then a fast spinning motor from a forklift geared down. Since the train really only needs to move at 5mph but will weigh 10 ton its kind of a weird situation and as I mentioned I'm not well versed in electric motors.
 

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Hi
Forklifts are heavy engineering - you are not going to be changing the gearing easily!
On the other hand they normally last for decades

I would be looking at the pallet tractor things
I would not expect to be getting a usable battery pack at those prices! - so take that into account

At the $500 level it is probably worth just picking one up and taking it to pieces to learn what you need - 10 tonnes is a LOT - Why not build the train aiming at 2 tonnes max?
- 5 Cars ~ 200Kg each and a "Train" at 1 tonne
2 tonnes for the unit and say 30 passengers - 3 tonnes
Giving 5 tonnes total
 

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Discussion Starter · #8 ·
I was more so thinking of just running a larger gear off the output of the motor, not reconfiguring the motor internally.
I apparently did my math a little too quick and it actually should be closer to 5 ton.
 

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a couple things you need to consider?

how much of an incline will it need to handle at 5mph?

is it using tires or rails?

how long does it need to go between charges?

You have to define the use case better before you design the machine.
 

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Discussion Starter · #10 ·
I would say 10 degrees of incline at most but the majority of the time it will basically be flat ground.
It will use rubber tires and driven mostly on pavement and occasionally flat grass.
I would like to try and get about 8-12 hours of total run time which includes constantly stopping and it sitting while being loaded and unloaded so I would guess 6-8 hours of actual driving time.
 

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You should consider a used cart and or components for electric/gas golf carts. Pickup a used electric cart for making your Engine and older gas chassis for cutting up and making your passenger cars.
 

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I found an electric golf cart for $2600:

http://baltimore.craigslist.org/rvs/5794418607.html

And a gas model for $1200:

http://baltimore.craigslist.org/grd/5766640271.html

You really don't need much power for a train on smooth flat surfaces. An 8800 pound EV on a 1% slope at 6 MPH needs only about 4 HP:

http://enginuitysystems.com/EVCalculator.htm

It needs about 17 HP on a 10% slope at 6 MPH, but only 3 HP at 1 MPH on the slope, which is probably only for loading using a ramp.

You might get by with a treadmill motor, which can be about 2 HP and can be pushed to about 2x-3x for short periods of time.

http://www.ebay.com/itm/Weslo-TREAD...R-WINDMILL-GENERATOR-LATHE-2-HP-/252554073724
 

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Discussion Starter · #13 ·
I found an electric golf cart for $2600:

http://baltimore.craigslist.org/rvs/5794418607.html

And a gas model for $1200:

http://baltimore.craigslist.org/grd/5766640271.html

You really don't need much power for a train on smooth flat surfaces. An 8800 pound EV on a 1% slope at 6 MPH needs only about 4 HP:

http://enginuitysystems.com/EVCalculator.htm

It needs about 17 HP on a 10% slope at 6 MPH, but only 3 HP at 1 MPH on the slope, which is probably only for loading using a ramp.

You might get by with a treadmill motor, which can be about 2 HP and can be pushed to about 2x-3x for short periods of time.

http://www.ebay.com/itm/Weslo-TREAD...R-WINDMILL-GENERATOR-LATHE-2-HP-/252554073724
That calculator is exactly what I was looking for. Thanks
 

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5 tons on grass is gonna have some rolling resistance.

edit: plus it looks like no gearing options yet, and hp is very rpm specific.
 

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I did a little figuring...


http://www.engineeringtoolbox.com/rolling-friction-resistance-d_1303.html

guessing about 1000 lbs force flat grass/mud/etc (tires inflated to max sidewall)
add another 780lb force for a 10 degree slope, so one way or another you need to come up with 1780 pounds of push from the drive wheels
at 5mph that is about 25hp for the off-road uphill sections (assuming it is geared for 1780 lbs of push at 25hp), plus some fudge. At that rate it would drain a 20kwh battery in an hour, so 6-8 hours run time might be challenging.
 

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Discussion Starter · #17 ·
I did a little figuring...


http://www.engineeringtoolbox.com/rolling-friction-resistance-d_1303.html

guessing about 1000 lbs force flat grass/mud/etc (tires inflated to max sidewall)
add another 780lb force for a 10 degree slope, so one way or another you need to come up with 1780 pounds of push from the drive wheels
at 5mph that is about 25hp for the off-road uphill sections (assuming it is geared for 1780 lbs of push at 25hp), plus some fudge. At that rate it would drain a 20kwh battery in an hour, so 6-8 hours run time might be challenging.
It would never maintain the angle during its use I mostly would like it to be able to do it just so that its capable of it when it is needed but the vast majority of the time its going to be rolling on flat concrete/asphalt. Thaks for the info that's the kind of stuff im struggling with for this project.
 

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Hi dovaka
Grass is a whole different ball game
Using forklift bits and chassis on concrete is OK - for grass you need something a lot lighter

You do have the option of using a shorter train on grass - but the chances of sinking in and being unable to get the locomotive out...

Other than the grass any of the electric trucks or forklifts would be fine - just make a light wooden "train" to go on top
 

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Another option for a 'locomotive' would be a Taylor Dunn warehouse truck. Something like a Taylor Dunn B2xx range would have ample pulling power on pavement.
https://www.taylor-dunn.com/vehicle_search.aspx?mode=base&type=burden_carriers

I have one as my own project (supplied under the Bradshaw name in the UK), Beryl the EV in my sig below.

They come up on EBay occasionally but can be found 'retired' in warehouses due to dead batteries and lack of TLC. The useful bits would be the front steering axle, the rear transaxle with motor, and the controller. A rotting chassis shouldn't be an issue for your project.
 
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