Which Is Easier To Pull? (Railcars vs. Road Cars)

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It's so heartwarming to see a civil engineer overcome their greatest fear and make a video all about something that moves

I'm a locomotive engineer. I've moved many stone trains. In fact, in 21 years, I've hauled pretty much anything you can imagine...including elephants. I chose the level path without the tunnel. It's the longest, therefore I get paid more to drive the train.

I find these videos utterly fascinating. When I show them to my dad, who's worked for the Union Pacific for 25 years? "I just got off work. I don't want to look at trains."

I work as a freight train conductor in Canada, and the largest train I've had was 36500 tons of potash. It was 256 cars and 4 locomotives. It was two locos on the head end, one in the middle and one at the tail. Very rare occasion they run a train that big.

I used to be the manager of a warehouse that had a rail spur for shipments. Many times, I had to move the box cars by myself. I used a 'Johnny Bar' to start them moving, and then I could just push them into place at the docks, fully loaded. No problem, IF THE BRAKE WAS OFF.

The rail wagon you were trying to pull had cold bearings. This makes a huge difference. A cold train has a 'dead’ feel to it whilst, an hours running later, the same train will feel much more ‘lively’. Not as pronounced on an all roller bearing train but on old white metal bearings, can add an extra notch or two to maintain speed.

Tyre pressure really makes a big difference to the rolling resistance of my car. I can tell almost instantly if a tyre is a bit low, by pushing it on my driveway. By the way, at 5:00, Grady forgot to mention that on electrified lines, most of the downhill force can be recovered by regenerative braking and fed back into the grid. And Grady pulling a wagon by hand brings to mind No 1111, 'Four Aces', a 4-8-4 steam loco built by Alco in 1930 for the Timken Roller Bearing Co to demonstrate the lower friction of roller bearings. At some stops, for publicity purposes, three men could pull this 300-ton locomotive.

I had a teacher, back when I was in 5th grade, who tried to move a rail car with a tractor. The tractor's tires just spun in place. He was stymied and thought it impossible. Another man handed him a steel bar, with an angled foot on one end, and said to use that. My teacher looked at the man and thought he was nuts. He stuck that foot in between the wheel and rail and put a bit of pressure on it and the rail car began rolling. It was the prime example of a lever for teaching our class.

Before watching was wondering how the question so simple needs a video this long for an answer. But now I see, it has never been about the answer, but the journey to it.

The most impactful practical example of what happens when friction is low for me was seeing just how easy it was to move stones that weighed several tons while they were being suspended by an excavator (we were building a retaining wall). It truly is amazing just how much friction matters.

I'm a train driver from Europe, and I found this super interesting and informative! When we occasionally had to move cars manually we used long steel bar chisels (not sure what its name is in English. Basically a 5 foot crowbar) as a lever under the wheels to get it rolling. Thanks for the video! Will definitely check out more of these!

15:20 a roller bearing car can be relatively easily moved manually, but plain bearings take quite a lot of force to get started. The railroad I volunteer at hosted a strongman competition with a boxcar pulling competition as one event. Our crew moved the car around with a locomotive just before each attempt to get a layer of grease in the bearings, otherwise even the strongest competitor couldn't have budged the car.

This reminds me of a demo i saw in a museum, they had a truck axle on asphalt and a train axle on a rail, both with a pull rope, and despite the train one weighing more than twice the truck's, they were noticeably easier to pull

Working in a stockroom/yard and the difference in rolling resistance between smooth, hard concrete and soft, grippy asphalt often makes the difference between being able to move a heavy pallet by hand with a pallet jack, or needing to get the forklift. And with a pallet jack, keeping the floor clean is all too important; a small stone, nail, or sliver of wood from the pallet itself can make a easy load impossible to move. The flip side is this; a smooth, hard and clean surface makes things much easier to move but much harder to stop. Without rolling resistance to slow things down, you have to deal with all of the inertia yourself.

I’ve been an inland merchant mariner for almost 20 years, an engineer for my company for almost a decade now. I love your presentation on this. I would love to see you do one on our industry that works somewhat behind the curtain, but in plain view. One thing i have learned is it it more cost effective per unit to move something in larger quantity. As a rule of thumb our boats burn one gallon of diesel per horsepower used per 24 hours run time. It is hard to think of something that burns 12,000 gallons of diesel per day as economical, but when you figure in the amount of work done for that fuel it absolutely makes sense. Id love to see you break it down. I do believe that our inland waterways provide the lowest resistance to moving large quantities of stuff in this country.

If you were wondering, the amount of rolling resistance from a cars tires is extremely dependent on tire pressure, tire type, and surface type. When i had my 3500lb jeep on stiff load range e tires with 80psi on a smooth shop floor, it literally took one finger to push. Now try pushing the same jeep but on more flexible four ply tires, underinflated at say 15psi, on a gravel road. Itll probably take two people. Pushing cars with flat tires is very very difficult.

I would like to have seen, at the very end, an illustration of the diesel fuel needed per ton/mile to transport that gravel by truck compared to by train. Otherwise, excellent video, as always.

I'll use an example, until 2001, Norfolk Southern ran down Saluda Grade and that was at the time the most steepest with 5% going down. From the summit at Salula all the way down to Melrose, trains had to use dynamic brakes to keep the trains at around 8 MPH and if you didn't keep it at around 8, you would be heading for the runaway ramp down at Melrose and you might get in some trouble (that is why you had the Road Foreman of Engines on board and he had a special key just for running trains down Saluda Grade)

You are really hitting it out of the park Grady! Absolutely love this series, cannot wait for the next video, thank you so much for putting so much work and time into these videos