4.2.1 Putting down the layout lines

Modeling Information

So we'e got our track plan schetched out on on a piece of paper where do we go from here? Depending on how technically advanced you are depends on what technique you use.

  • If you have been using a Computer Assisted Design (CAD) program to help you design your layout, that program may have a print process that will print a roadbed to proper scale. It then is a matter of laying the sheets of paper out on your benchwork and either tracing or gluing the paper down.
  • There are articles in Model Railroad Planner where layout owners were fortunate to find track diagrams or engineering drawings that they could blow up to scale and use.
  • Many designers use the pencil and pen process to put down the lines. This is the most often used technique.

Center line. It is a universal rule of thumb that the track line identified by Lynn Westcott and other is the track center line.. This comes from the early days of sectional track and cork roadbed. The cork roadbed is sliced down the middle and the track center line is used for aligning the cork before gluing. The sectional track had a series of nail holes in the center of the tie strip that is used to center the track on the cork.
 
Laying out the right of way

Center Line technique. When physically laying out the right of way, Lynn Westcott in his book 101 Track Plans for Model Railroads identified six steps for locating track lines on the layout. In order they were:

  1. Locate all curves that swing near the outer corners of your space. Draw the curve beyond each end for a ways. 
  2. Locate other curves in the same way. 
  3. Locate the main and ladder tracks of your yard. 
  4. Add connecting tracks everywhere. 
  5. Where connecting tracks include track switches, locate the straight track first. Then locate the branch as a straight line at the proper switch angle.
  6. Where those lines cross is the point of intersection of the switch. 

If you are laying track on a 4'x 8' sheet of plywood, or are building a layout other than point to point (what some refer to as a spaghetti layout design) locating curves first IS the way to go. I have found in my modular layout experiences over the years that laying out the straights first are more important.

WWSL specific technique - tie edge

Having done this a few times I have learned that I hated using track centers for laying track on roadbed. While necessary when using cork roadbed products, my recurring use of foam panels permits me to use the straight side of  flex track and turnouts for more reliable track laying. This does however require some rethinking of putting down the track lines :
  1.  Modification of curved templates (subtracting 1/2 the length of the tie (approximately 1/2 inch from the curve radius) to get the tie line rather than the center line.
  2. For yard ladders, the yard layout line is along the straight part of the turnout. For finding the final alignment of the turnout with the yard track, i align the last two ties on the turnout diverging route to the tie line of the yard track.  NOTE: I'm using Shinohara/Walthers turnouts that have a straight rather then a curved divergent track. Your turnout alignment technique may vary.
Advanced Preparation

Templates can  be used to check or develop track designs and serves as guides in laying ties and rails. The templates are created, cut out and laid in position on the roadbed. The templates are moved along the roadbed by eye as necessary to test track arrangements until the most desireable arrangement is developed. 

I created the following templates to assist me in laying out the right of way:

I have also developed templates for the following under track items:

  • drain pipes and box culverts (by WWSL Common Standard design).
  • electro-magnetic uncouplers
  • unloading pits
  • hand and motor car set-offs
  • grade crossing widths
  • rail rest locations

These templates can be based on prototype practice, NMRA recommended practices, or whatever standard you decide to use. 

I have identified WWSL right of way templates throughout the Section 4 Right of Way reference pages.  To construct a curve template See 4.2.1.5 Curve radius template for additional details.

Note: The WWSL is a traction railroad. My right of way templates include cantenary pole placement practices.

Project Process

Tools needed
  • Templates identified above
  • Metal straight edge
  • Track radius tools
  • Sharpies of various colors - i use black, brown, red and silver.
  • An exacto knife for cutting the lines into the styrofoam.
Putting down the lines

I use the following steps to locate track on the WWSL.

  1. Locate the edge of the layout boundary line. For the WWSL thats the facia that runs along the front of the layout. 
  2. Locate the main and passing tracks. Cut the initial straight lines with the metal straight edge and exacto knife. Mark the cut lines with a silver Sharpie.
  3. Locate the easement line. Cut the initial straight line with the metal straight edge and exacto knife.
  4. Locate the curves along the easement line. Cut the initial curved lines with the curve template and exacto knife. Mark the cut lines with a silver Sharpie.
  5. Use the easement template to merge the curve with the main line cut lines. Identify the points of tangent (PT) and point of curve (PC). Cut the easement curve with the exacto knife and mark the cut lines with the silver Sharpie. 
  6. Locate the track turnout based on the track plan. Very carefully align where the turnouts will be located. Re-align the turnouts.  A lot. Mark the head tie location with a red Sharpie. Mark the frog location with a green Sharpie  Note: If you're comfortable with your turnout template, make copies, glue down the turnout template for drilling switch bar and feeder wire locations. 
  7. For passing tracks, I use two turnouts and a straight track gauge to aid in constructing the turnout curve. (I use the second turnout as the passing track turnout curve to the main line, then use a metal straight track gauge to align the turnouts). Mark the Point of Curve (PC) and straight track between the two turnouts, and cut the easement curve and mark with the silver Sharpie
  8. Locate yard and ladder tracks using the yard ladder turnout template. Cut and mark as described.
  9. Mark finalized tie lines for straight, easement, curve and yard turnout lines over the Silver Sharpie/ exacto lines with the black Sharpie.
  10. Mark bridge abutment location lines with blue Sharpie over exacto lines. Use a carpenter square to ensure the perpendicular to the track (when appropriate).
  11. Use the appropriate templates and mark ballast and drainage lines in black Sharpie.
  12. Use the appropriate templates and mark embankment and hillside start lines in brown Sharpie.
  13. Mark structure foundation lines in orange Sharpie.

The black Sharpie line is your near tie line for gluing down your flex track, turnouts, etc. 

General Guidance

Like any well laid out plan, something happens that makes it necessary to make a change. Some things to watch out for while putting down the right of way.
  • The shortest distance between two points is a straight line. Watch for rails that don't come together straight (kinked).  
  • Be sure to have several inches of straight track before entering a turnout or crossing a bridge. Most commentators I've read suggest a minimum of two inches in addition to the straight section of a turnout. (See reverse curve comment.) Thru truss bridges may require more straight track on the approach when coming out of a curve.
  • Remember your right of way specifications when it comes to crossovers, tunnel portals, signal posts or towers. Especially on curves!  
  • Beware the S-curve in reverse curves, crossovers and yard ladders.
  • Track work should flow. Avoid multiple reverse curves and changes of direction. If you are comfortable with the idea of easement curves, use them.
  • Track should be level throughout turnouts, particularly in respect to cross level rail to rail.
  • Avoid changes in sub grade under special track work such as turnouts.  
  • No breaks in sub-roadbed, within one car length of a turnout.    
  • Use the largest radius curve possible without violating other rules above.

References

Paul Mallery, Trackwork Handbook, Clifton House. 

Lynn Westcott, 101 Track Plans for Model Railroads, Kalmbach Books






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