Does COAL size matter in STEAM TRAINS? | Railroad 101

Does the size of coal matter to a steam locomotive? We've talked about it before, but this shows some fun data from a few runs of Polar Express at the
@coloradorailroadmuseum

Become an ES&D Train Crew Member and get extra perks!

[SignalLightProductions]

As a fireman, I will add two things to this. I think it's harder to get as full of a scoop of powder as lump coal since it only goes about the height of the shovel wings. Secondly powder has some advantages, both for capping your bank and getting fast heat in the box if you spread it out. No fun if you aren't working the engine hard though.

[robertbalazslorincz]

In Hungary we had a saying in the 20s:
"Kűfőd szén" ('stonedirt coal')
it refers to sh*t coal that barely even burns because its composed of dirt and stone

[fudgebaker]

I can attest, slack coal is one of those problems that firemen like to avoid, and by "avoid, " I mean pass on to the next person. When there really isn't anything other than slack left, rather than use that, they'd rather fill the tender with fresh coal (on top of the slack) and use that, thereby increasing the amount of slack in the tender over time. I remember when I decided to fire with almost nothing but slack, and our line is at a constant steep grade. On the way up on the last trip of my shift, I had to shovel almost every 30 seconds or minute to keep up with demand. I had made them into clumps of wet dirt, but it still almost instantly vaporized the moment in went in the hole. To my credit though, the tender was almost exactly empty when we arrived back in the yard. :D

[missydg]

My grandmother furnace was a coal burner in 1966 when I was ten years old. Cold January day in Michigan so dad told me to stoke the fire with coal. Little 10 year old me loved steam locomotives and here grandma had one in her basement. So I stoked it up because this train had to make it over the mountains in my mind. My dad came running downstairs yelling at me what I was doing. My reply was building up steam to get this locomotive over the mountains.
As my father would tell the story grandmother house was over 90 degrees inside and all the windows were open. Unfortunately I used a month of coal per my dad. Also I was covered in coal dust. I do remember shoveling in the coal. That summer my father paid for conversion to natural gas furnace. Dad gave me the coal shovel as a gift and reminder.
I still have that coal shovel and have visited the Colorado Railroad Museum.

Great videos Hyce.

[JT]

It definitely matters with the 1/8th scale locos too. In my loco in particular, if you use nut coal you'll find it's steaming capabilities rather lack luster in comparison to using pea coal. Rice coal is almost small enough to fit through the grates but while it's in there it'll burn out quick.

[ThatoneGuy]

At 2:07, that is some of my favorite audio I think you've ever produced. Not the conversation, but the way the mics picked up the bassy, deep thrum-rumble-thrum-rumble, that chugga-chugga... I love that sound. Machinery breathing at work.

[AlRoderick]

In the coal-fired power plants that I've seen depicted in museums and on YouTube elsewhere they tend to use pulverized coal. That's extremely fine powder, but they introduce it to the boiler being blown in with a jet of compressed air and it burns in the air before the ash settles down. I would suppose that an auto stoking engine like a big boy as seen in the Animagraphics video recently would have an easier time with slack coal because it would just lift it up and blow it into the fire without much issue, and it would likely burn before it even touched the firebed.

[Yardmaster_Media_]

I hope that you're able to sort out whatever went wrong last year with the Polar Express movie reaction. That would be great to see that come to the channel next month! I'm sure that a lot of people would like to see an actual railroader's perspective on the movie!

[TheMostUt]

Before watching the entire thing, prediction: Smaller particles have greater surface area, which means fire will move faster through slack than lumps. This would present (given equal air flow through the box) as a fast, hot fire, but likely with less overall energy content. The flame may be hotter, but with less burn time (unless the powder is literally FLOWING into the box) the burn will happen in phases, a hot phase and a cool phase. Since boilers work (water=BIG thermal inertia) on AVERAGE temps, the water temp would ~remain the same~. End result= more shovels, more human work, same or slightly reduced engine performance.

I would love the engineers' talk on boiler thermal inertia and effects of coal size, injector flow rates, etc.

[ZergRich]

I would think with a giant piece (dinosaur egg had me lol-ing) you might actually break something if you threw it into the firebox the wrong way. And regarding the dust, I would think it would just burn too fast to even be worth trying to use, but apparently it works even if it makes the fireman work harder. I learned something! Keep the great content coming Hyce!

[therocinante]

This has become one of my favorite channels. Thanks for all the videos and thanks for getting me into DV!

[FJX_Productions]

When I fired the K-28s and K-36s on the D&S we had large coal like the good stuff you were using. But towards the end of the day you’d start getting into that crummy stuff and it just stunk. I heard though that back in the day with certain railroads, obviously the grades of coal would vary depending on where it’s from, but the standard size of the coal chunks was smaller than what we use today. Probably about half the size, which I guess made for a more even burn. But who knows 🤷‍♂️

[kosmostimber]

you knew exactly what you were doing with that intro 💀💀💀

[Shadowtiger]

One potential use for that fine dust is models.
I like to grind up coal using a pepper grinder to a consistent grain size and then I use that on coal hoppers and in SL tenders to model the coal.
I find it looks better than the commercially available coal modeling products

[Buynot]

I've been on a bit of a kick of watching videos from the end of Chinese steam from the 80s and 90s through to the mid 2010s, and whenever there's a glimpse into the cab, the firemen there are almost always using what seems to be a lumpy powder that only vaugely resembles coal. The entire time I was thinking "that can't be good for the engine OR the fireman." The timing of this video was perfect for me and pretty much answered the questions I had, so for that I thank you!

[KerboOnYT]

I've only ran wood fired steam but size matters there as well. For example, use big chunks for a slow burn if you're idle but want to keep pressure or use small pieces for a quick, hot fire when needed. Fun video!

[patricksheary]

Hi Mark, a very nice expanded explanation of what Dusty showed us during your previous in-cab video. I really like how you explain square cube law and how it applies to volume and surface area affecting combustion. This put Dusty’s valuable comments into sharper focus, burning flammable dirt makes the fireman work much harder to keep up with the quickly burning coal bits. I really enjoy your deep dive detail videos from which I learn so much. Many thanks again Mark for this excellent tutorial. It’s like taking a choo choo graduate course. Cheers to you Professor!

[sambrown]

The only firing I've done is chucking wood into a 1917 40-horsepower Case steam tractor, which is very different to coal firing a locomotive, but it's still something. I also got to run the old girl, which was actually surprisingly easy, since you really only need to worry about the steering wheel, the governor takes care of the speed. You only need to touch the clutch if you want to idle the thing or run something off the flywheel, and you only need to touch the johnson bar when you've just gotten moving, and you want to hook it up, though you only get 3 notches each forward and reverse. It does have a handbrake, but it's really only useful for controlling speed going downhill, or as a parking brake. The thing also had chain steering like most steam tractors, so you need to constantly correct the front wheels, as the slack in the chains allows them to pivot a bit, even when the steering wheel's not moving. She also had the most atrocious ride quality of anything I've ever ridden.

[ducewags]

When I was a small Duce, great gram showed us, my brother and I how to cook with food. Her statement at the time, "if it's larger then the arm, it won't feed the belly, as you don't get the heat needed to cook". I burn wood and go by that idea for heat. Coal, never gave it a try and you never want to mix coal with wood as that will make an acid that will eat the pipe. Might be a show, or get talked about by Hyce some time, maybe? Thanks for the shows Hyce, and the schooling that goes with it.

[CTW-G]

Watching hyce makes me so excited for my trip to Durango next summer! So excited!