Help me understand the Loco terms.


B

BamaMan

Roll Tide! Dothan, Al
I am sure somewhere this is explained, but its so much easier to just ask yo guys. When I am looking at new Locos, they all have 0-8-0 or 0-4-8 or whatever after the name. What exactly do the numbers mean? I am sure this is a very elementary question, but its coming from a very elementary guy when it comes to the trains. ;)

Thx
 
Its steam wheel configurations and 0-4-0 has no front pilot wheels and no wheel under cab...a 2-4-2 has 2 small front wheels, 4 large drivers, 2 small ones under cab like o OOOO o. etc.
 
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Trucula said:
Its steam wheel configurations and 0-4-0 has no front pilot wheels and no wheel under cab...a 2-4-2 has 2 small front wheels, 4 large drivers, 2 small ones under cab like oo OOOO oo. etc.
Click to expand...



Oh ok thx. Explains it well for me.
 
It is called the Whyte Notation, and is not used universally by any means...so don't log on to a European steam fan forum and expect to get approving and knowing nods about descriptors using Wyte Notation. In fact, the Europeans use only the wheels on the one side. That would make the Midado type with 2 pilot truck wheels, 8 drivers, and two trailing truck wheels a "1-4-1".

The Whyte Notation counts all wheels which support and guide the engine proper, which is why the Mike gets the designation 2-8-2. Accordingly, wheels on both ends of the axles are counted, contrary to what is stated above.

-Crandell
 
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Good points made.....the #'s are for total wheels...so from a side view divide each # in half...so a 2-8-2 would show 1-4-1 from each side......Tracula's last little pic actually shows a 2-8-2, not the 2-4-2 he was discussing. As far as what the numbers correspond to, the front sets of wheels are to help guide/steer the engine and support the front of the engine on long wheelbase engines, the next set(or sets....articulated engines can have multiple sets , like 2-6-6-2) are the drivers which put the power to the track, and the rear set is to help support the weight of the firebox. A bigger firebox generally equated to more power, so in theory a 2-8-4 would have more power than a 2-8-2.
 
DOes anyone know if they have a 4-8-8-4 in HO? the 4-8-8-4 was known as Big Boy and the largest steam loco ever built.

There is no way it will take corners very well if there is one, just wondering if anyone knows of one.

One of my favs that not available in ho but in N is the 2-10-4. It would also be nice to find a 4-12-2 which was brought in by Union Pacific.
 
MRLdave said:
Good points made.....the #'s are for total wheels...so from a side view divide each # in half...so a 2-8-2 would show 1-4-1 from each side......Tracula's last little pic actually shows a 2-8-2, not the 2-4-2 he was discussing. As far as what the numbers correspond to, the front sets of wheels are to help guide/steer the engine and support the front of the engine on long wheelbase engines, the next set(or sets....articulated engines can have multiple sets , like 2-6-6-2) are the drivers which put the power to the track, and the rear set is to help support the weight of the firebox. A bigger firebox generally equated to more power, so in theory a 2-8-4 would have more power than a 2-8-2.
Click to expand...

Sorry my bad...I didnt have my morning coffee when I was typing...LOL..I had it in my mind, it just got lost when it got to my fingers.. :D

And yes they do make a 4-8-8-4 in HO... I have a Rivarossi Challenger 4-6-6-4 and it works well on our curves...smallest is 22in. Some engines even tho have multiple wheels were made for smaller radius by not having flanges on the center most wheels. (meaning all middle wheels of the driver sets had no flanges)

Here's a couple big boys on eBay:
http://shop.ebay.com/items/4 8 8 4 big boy?_dmd=1&_sop=12
 
Don't forget the old "0 5 0" that shows up on layouts from time to time when no-one is watching! :D
(meaning fingers)
 
midrange said:
DOes anyone know if they have a 4-8-8-4 in HO? the 4-8-8-4 was known as Big Boy and the largest steam loco ever built.

There is no way it will take corners very well if there is one, just wondering if anyone knows of one.

One of my favs that not available in ho but in N is the 2-10-4. It would also be nice to find a 4-12-2 which was brought in by Union Pacific.
Click to expand...

There are any number of 2-10-4s out in h.o also the 4-12-2 is available but only in imported brass models.
 
Midrange.....generally, engines with multiple sets of drivers are articulated, meaning that the sets of drivers actually were free to pivot, allowing them to turn as easily as other engines. There were a few really oddball combinations..like a 2-6-6-6-2 (or something like that) where the rearmost set of drivers were fixed, but the front 2 sets could pivot. In fact most articulated engines were designed for "mountain running" where the track tends to be a little curvier. As Trucula says, most of the model articulateds do pretty well on curves....I have a 2-8-8-2 in N scale that will handle 9.75" radius curves with no problem....it looks really bad doing it, but it physically handles them.
 
If you are interested in a Big Boy in HO, Broadway Limited Imports (BLI) makes one in its DC-with-sound Blue Line series. If you were to want to run it in DCC, you'd need a second decoder capable of operating on a DCC system, and only to control the motor.
 
Big articulated locos like the Big Boy have always been very popular with model railroaders. Just off of the top of my head, I can think of at least 12 manufacturers/importers of the models in plastic, diecast and brass!

Some are still available and some haven't been produced since the 1950's
 
Selector said:
It is called the Whyte Notation, and is not used universally by any means...so don't log on to a European steam fan forum and expect to get approving and knowing nods about descriptors using Wyte Notation. In fact, the Europeans use only the wheels on the one side. That would make the Midado type with 2 pilot truck wheels, 8 drivers, and two trailing truck wheels a "1-4-1".

The Whyte Notation counts all wheels which support and guide the engine proper, which is why the Mike gets the designation 2-8-2. Accordingly, wheels on both ends of the axles are counted, contrary to what is stated above.

-Crandell
Click to expand...

Exclude the UK from Europe for this one, we use the Whyte classification too!
 
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