A "Block" is a group of cars that will be handled together from a location to the next place the cars are classified, interchanged, change trains or spotted at industry. The cars may be different final destinations. Blocks may be differentiated by :

• Final destination
• Interchange road
• Next switching location
• Car type
• Industry
• Direction
• Next train

Blocks are identified by a block name or code:

• Text name (Houston)
• Alphanumeric code (HOU1)
• Numeric code (135)

Blocks are used in classification yards to separate the cars. Each classification track may hold one or two blocks. Blocks are also used to assemble trains, a particular train sysmbol or schedule will carry only certain blocks. The blocking pattern is described in a "transportation plan" for the train. One special type of blocking, particularly used on locals, is station order blocking. The cars are blocked by the destination station and the train is assembled with the blocks in order from the front of the train to the rear of the train in the same order the train will arrive at the stations. So if a train originates at Anna and operates on the route Anna-Bess-Cloy-Dora-Eve-Fay, the train will be blocked:

Caboose-Fay-Eve-Dora-Cloy-Bess-Engines

It is also possible, that a train such as the one above may be blocked in the reverse manner as follows:

Caboose-Bess-Cloy-Dora-Eve-Fay-Engines

This will more likely be trains that run over several sub divsions where the blocks will be added and removed at crew change points by yard switchers.

Classification yards

Classifications yards are arrangements of tracks used to sort or classify cars. They recieve inbound trains or cuts of cars, switch them according to their outbound

Curve radius rule-of-thumb

 Here are some curve radius guidelines based on the lengths of your longest pieces of rolling stock.

2X - Some model equipment may be able to track reliably on 2X their length, but this is generally considered pushing it.

3X - Making your curve radius at least 3X the length of your longest cars gets reliable tracking around curves, but looks toylike.

4X - If you make your curve radius at least 4X, your longest cars will look much better on curves.

5X - If you make your curve radius at least 5X, your longest cars will couple easily with minimal manual fiddling of the couplers.

This measurement is based on the length of your longest car (coupler to coupler).

HO EXAMPLES

For example, an HO forty foot box car is about 6" long, coupler to coupler. Here are the curve radius guidelines if your longest cars are forty footers:

FORTY FOOT CARS
Curve Radius
2X - 12"
3X - 18"
4X - 24"
5X - 30"

If you go below an 18" radius, your cars may not track well on curves, although some equipment may still track okay down to a 12" radius. You need at least a 24" radius for your cars to not look toy-like on curves. To have reliable coupling on curves, you need a 30" radius, which would be a good minumum radius standard for a yard on a curve, for example.

However, few will have only forty foot cars as the longest cars on their layout. Here are some guidelines in HO for other more common "longest" car lengths:

FIFTY FOOT CARS
Curve Radius
2X - 15"
3X - 22.5"
4X - 30"
5X - 37.5"

SIXTY FOOT CARS
Curve Radius
2X - 18"
3X - 27"
4X - 36"
5X - 45"

EIGHTY FOOT CARS
Curve Radius
2X - 24"
3X - 36"
4X - 48"
5X - 60"

So to summarize, some cars or locos may track okay at 2X, but at 3X cars of that length will all track well, use 4X if you want things to look decent, and use 5X if you want reliable coupling on curves (like say a yard on a curve).

Further comments

Here's another trick you can take advantage of, too. Curves, when viewed from the inside, don't look as sharp. So for inside curves, you can drop the radius to 3.5x instead of 4x (say 27" instead of 30" for 50-foot equipment) and the curve will still look pretty good.

But outside curves (like at the end of a peninsula) look sharp and the equipment doesn't look as good, so the curves there should be as broad as possible. If you can manage it, you should use the 4x rule (at least) for those curves.

If all the cars are of similar length, you can drop to perhaps 2.5x, but if you have a mix of longer and shorter cars, you'd better go at least 3x of the longer equipment if you don't want tracking problems, or 5x of your longest equipment if you want the most reliable coupling. Widening the gauge to maximum may help with rigid wheelbase steam locos.

You may also be able to do 3x on longer equipment and get reasonable coupler performance if the couplers have been altered to allow them to swivel at least 50% of the width of the car.

To be absolutely sure what works best with your equipment, do some testing on your own, using these guidelines as a starting point.

Curves

Prototype railroads in North America measure curves by degree of curvature, not radius. The degree of curvature is measured by in the field by the offset of a 100 foot chord.

For a prototype curve:

R=Radius of the curve

D=Degree of curvature

R=50/sin(D/2)

So for a 4 degree 30 minute curve:

R= 50/sin(4 deg 30 min/2)

R= 50/sin(2 deg 15 min)

R= 50/.0392

R= 1275 feet

To convert to HO radius in inches:

Rho= (R/87)x12

Rho= (1275/87)x12

Rho= (14.655)x12

Rho= 175 inches

Typical mainline curves are in the 2-6 degree range. Sharp curves are those above 10 degrees.

United Kingdom

In the United Kingdom and most countries that belonged to the former British Empire, prototype curves are commonly measured by radius. In pre-metric times, the radius was often measured in chains.

1 chain = 22 yards = 66 feet.

Easyspline masonite roadbed

When I started in this hobby I used Woodland Scenics foam roadbed but after reading about Joe Fugate's Easyspline masonite roadbed I decided to try it out and WOW, what a difference.

I started by adding my risers made from 1 by 2.

Sanborn map

Sanborn Insurance Maps were made of 12,000 cities and towns across the United States by the Sanborn Map Company beginning in the 1867 for the purpose of assessing fire risk and setting insurance rates, and they were the primary American publisher of fire insurance maps for nearly 100 years. They include not only moderately detailed information about the location of structures, railroad tracks and streets drawn at a scale of 1"=50'-0", but they also include the height and material of the structures, location of doors and windows, cranes and other equipment, storage tanks, use of the building, etc. An invaluable tool when researching for a model railroad, they, along with photographs, track charts and ICC Valuation maps, can give a very accurate rendering of what was happening in most any urban area of the country begining around 1900. These maps can generally be ordered via Interlibrary Loan from your local public, school or university library if you have a library card. Some libraries will have the maps for the local area or state on hand in hardcopy format, and maps that are borrowed from other libraries will generally be on microfische or microfilm. Copies can be made for personal use.

The map below shows a part of the Bethlehem Steel Shipbuilding Yard along the Hudson River in Hoboken, NJ. The railroad tracks shown belonged to the Hoboken Shore Railroad, and run out on a 600' long pier. All the different phases of shipbuilding work can be identified in the map from rigging to copper smithing to painting.

Timeline-Freight cars

Train length and layout design

How you design your layout's passing sidings, yard tracks, and return loops can have a major impact on train length. In this tip we discuss briefly what the issues are.

You can have trains longer than passing sidings and yard tracks and can deal with them, although they will slow things down a lot. But a train longer than a reverse loop will not work -- the laws of physics says two objects cannot occupy the same space at the same time — so the front of your too-long-for-the-reverse-loop train will collide with the back of the train once it reaches the end of the loop!

With passing sidings, the key is opposing trains. As long as one of the two opposing trains will fit, the other train can be any length — you can get the trains past each other with a bit of advance planning. But if both trains are too long for the siding, you'll need to do a double-sawby maneuver. Such a maneuver is fun once in a while but it would get old if it was standard operating procedure. This means passing siding length has a major impact on train length if you want opposing traffic to flow smoothly.

With visible yards on the layout, a too-long train can always "double the yard", which means you split the train in two and it takes two yard tracks. This practice is not uncommon on the prototype so it could be an acceptable operating procedure as long as you are aware that it will slow down yard operation somewhat.

Finally, too-short staging tracks can be a problem, since it will make you "double the yard" in staging as well. Requiring trains to do this in a visible yard on the layout is one thing, but requiring this in staging is going to get old, so the recommendation is don't. Staging track length has a major influence on train length.

More information

Uncoupling methods

One decision that a person designing a new layout must consider is how he/she plans to uncouple cars on the railroad. Since the vast majority of model railroaders at this time use either Kadee couplers or a clone, I will discuss the two major ways of uncoupling them.

The first way is by the use of a magnet positioned underneath or between the rails. The couplers to be uncoupled are then stopped over the magnet, slack run in allowing the knuckles to move to opposite sides and allowing the engine to move one car away from the other. These magnets may either be of the permanent or electrical variety. The pro's of this method is that no one needs to reach into the layout to uncouple cars and risking the possibility of damage to either the railcars or the layout scenery. The con's of this system is that you are limited in where you can uncouple, i.e. no magnet no uncoupling, and if your train takes slack at the wrong place or stops with cars over a magnet you can get unscheduled uncoupling (can be avoided with electromagnets or movable magnets). The magnets will allow you to set you couplers for delay so that you can push a car to a desired spot, this will not work on a track with several spots that need to have cars not coupled together when properly spotted thereby requiring multiply magnets on a track.

If you are going to install magnets, it is best to decide where they will be needed early in the design stage or at least by the time of track construction as they will affect sub roadbed and roadbed. Location must considered, as placing a magnet closer than a car length to a curve can hinder uncoupling (possibly worse on curves bending to the left when coming off the straight section of track.

The second popular way to uncouple is with a manual aid such as a pick which may be as simple as:

• flat blade between the knuckles
• special tool between the knuckles
• pointed tool (skewer) between the knuckles
• rod from above to catch and move the "air hoses"
• Z rod from the side to move the "air hoses"
• two magnets (wands a la Rix) that can be lowered between next to the couplers.

The major pro of the pick system is that it allows for uncoupling at any location on the layout that can be reached. Many operators feel that this helps to simulate a brakeman working the cut lever on a real railcar. The con's are that reaching into the scene destroys the illusion of the model railroad, i.e. no large hand from the sky with large telephone pole uncouples on a real railroad, plus if not careful one can damage cars or scenery.

One thing that must be stated is that the use of either system is not exclusive; you can have both magnets and use a pick to uncouple cars. This will always be a matter of personal taste of the layout owner.