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“any load a steam locomotive can start from a dead stop, it can haul”
You’ve got this, little meme locomotive!
Is this saying something significant or just a tautology?
It’s a railroader saying. Steam makes 100% torque at a dead stop so if it can start moving it can haul it.
So it means if our little train gets going nothing can stop it.
For comparison a diesel-electric locomotive makes 300% torque at a dead stop so it can move things it cannot haul for long distances. The motors would catch on fire or you would burn out your electronics.
Another railroader saying that sounds like a tautology is
“Steam can’t start a load it can haul. Electric can start a load it can’t”
Oh that’s very interesting. I thought starting to move is harder than keeping things in motion
In order of most frictiony to least frictiony
Stiction (stationary object you forced to move)
Rolling
Sliding
Which is why ABS exists. When you lock your wheels up your coefficient of friction tanks and your stopping distance can double or more depending on conditions. ABS unlocks your wheels sometimes so you can at least steer, unlike a skid. If you know how to pump brakes properly a skilled driver can beat ABS handily.
There’s also the fact that couplers have these hard rubber disks that act as springs and shock absorbers (railroading is kind of caveman-like in its solution to things) so when you try to pull a train it might look like you’re moving but you’re just taking the slack out. If you don’t you can bust a coupler from shock loading, so you can’t cheat physics that way (how I move heavy furniture around by myself personally so you would think it applies to trains)
As a result you take the slack out of a train and make the cylinder part of the boiler until:
A) she moves!
B) your wheels slip!
Once it’s moving it’s easy going.
As for why an electric engine can’t keep hauling overloaded it’s because it’s above 100% rating. It can only do that for a short while or things start melting and letting out magic smoke.
A steam locomotive can haul anything it can get moving since it’s lower friction once rolling, and requires less drawbar force.
I see. So the difference is that electric motors can provide a momentary burst of torque which is higher than their sustained capacity. And steam engines can’t do that, if they could, then the same “problem” would arise for them, right?
Yup! Which is why some steam trains had starter gear or “boosters” which was a 3rd piston geared down a lot into a normally unpowered axle. It was only active at low speeds but provided extra starting torque to get things moving
Oh, so it’s less about the physics of starting, more that starting is brief so for some engines, you can start moving but at an unsustainable setting?
No it’s about if steam has the torque to start moving it can haul that train without issue, while electric always has the torque to get itself into deep deep trouble if mishandled
But that trouble is that it would cause itself damage, not that it would start and then just somehow stop?
Yeah electric would move but could only do it at a crawl and would overheat rapidly. It’s a bit like hooking your Honda civic up to a semi trailer and then trying to haul that 500km in first gear… You’re gonna have a bad time.
Yeah, I was also really confused initially. Because it seems to indeed be a tautology, or maybe it’s a shitpost
It’s a common railroader saying I replied to the other commenter with more details if you’re curious
You can do it little train!
Obligatory fuck Rob Schnieder, maga supporting pos who wants us to go to war and reinstate the draft.
He can go first.
He really did fall off
In the digital age the saying “Don’t meet your heroes” can be interpreted as “Don’t check your heroes’ social media or public statements”
Though he was no hero of mine, it was pretty fun to try to see him in Adam Sandler films back in the day.
Hey, look, I feel seen! Yayyy!
Ganbatte train-san!