Module Construction Standards

Construction and Assembly

  1. Modules shall consist of a butted grid of 1x4 wood with a 1/2" plywood top. All construction shall be screwed and glued together.

  2. Size: Width 24" to 30", length 2', 4' or 6', height when erected: 40" to the top of the mainline roadbed.

  3. Modules shall be constructed so that the front edges of all modules are in line.

  4. Legs shall be made from 2x2 lumber 38 1/2" long. (See figure 3.) Legs are bolted to the sides of the module with 1/4-20 x 2 1/2" carriage bolts, 1/4-20 wing nuts and 1/4" fender washers. For height adjustments, 1/4-20 x 2 1/2" hex head bolts in 1/4-20 'Tee-nuts' shall be installed in the bottom of each leg. (See figure 3.) The Tee nuts shall be cemented into the legs to prevent their loss.

  5. Modules are clamped together with adjoining modules by the use of two 2" size 'C' clamps at each interface.

Standard Rectangular Module Materials


  1. Plywood for tops. 1/2" A-C grade exterior plywood, smooth side on top.

  2. Side rail for 4' module frame. Standard 1x4 by 4', wood to be straight, free of loose knots, and containing no knots greater than 3/4" in diameter.

  3. Cross rail for module frames. Standard 1x4 with length as needed to fit flush between side rails.

  4. Glue blocks for rectangular frames. Standard 2x2, 3 1/2" long.

  5. Glue blocks for corner module frames. Standard 2x4 cut at 45 along the length into equal pieces. These pieces are to be 3 1/2" long.

  6. Legs for modules. Standard 2x2 38 1/2" long, ends to be prepared as per Figure 3 of the Module Construction Standard.


  1. #6 x 1 1/2" flathead phillips wood screw for screwing together top and framework.

  2. 1/4-20 x 2 1/2" carriage bolts. 8 needed.

  3. 1/4" fender washers. 8 needed.

  4. 1/4-20 wing nuts. 8 needed.

  5. 1/4-20 Tee nuts. 4 needed.

  6. 1/4-20 x 2 1/2" hex head machine bolts. 4 needed.

  7. White glue or carpenter's glue for joining wood.

  8. Paint--dark brown water base latex to protect wood and improve appearance. Paint module top, sides and legs.

Figure 1 - Standard 4' Module

This what a standard module looks like in its most basic form. It has a 1/2" plywood and a standard 1x4 framework, glued and screwed together as shown. The legs are attached with wing nuts, so no tools are needed for setup. The module can be either 2' or 2'-6" wide and is 40" from floor to the top of the roadbed.

The module has proven to have good stability once assembled with other modules in a layout. No further bracing is desired. (You may want to add cross bracing when using it by itself at home.) It is light, strong, durable, simple to assemble and level, and it forms a stable foundation for your trackwork and scenery.

Figure 2 - Framework

All numbers refer to the above materials list.

Standard 4' Module

Standard 6' Module

Figure 3a - Fasteners and Legs

All numbers refer to the above materials list.

  1. These 1 1/2" x 1 1/2" corner reinforcing blocks are screwed and glued in place.

  2. These are the minimum and maximum standard widths. Narrower modules don't allow for enough scenery. Wider modules are difficult to handle and are hard to lean across to fix derailments.

  3. Modules wider than 24" shall have extra crosspieces, shown by dotted lines. Rule of thumb - 1/2" plywood should not span more than 24" in more than one direction.

  1. Screw heads must be flush or slightly countersunk so that they do not prevent modules from being clamped together tightly.

Figure 3b - Fasteners and legs

All numbers refer to the above materials list.

Side and front views

Front view of module with leg

  1. The leg top is not long enough to touch the module top. The weight of the module is supported by the side rails, which rest on the step cut into the legs.

  2. The Tee nut goes into a 5/16" hole which is of 2 1/2" minimum depth. All chips and dust must be removed from the hole before installing the Tee nut. Glue the Tee nut in place to prevent its loss.

  3. The wood screws are offset 1/4" vertically, so that they do not hit each other in the glue block.

  4. The mating face shall be square with the plywood top to prevent gaps, dips, and bowing when modules are clamped together.

Corner Modules

  1. Corner modules shall be constructed as shown in figure 6. Curves on corner modules shall be constructed as shown in figure 7.

  2. Corner modules with curves of greater radius are permissible. These modules or module groups must be the equivalent of a square with sides that are a multiple of two feet, at the point where the module or module group mates to the adjacent modules. For example, the standard corner module is the equivalent of a four foot square.

Figure 6 - Corner Module Frame Specifications

The basic corner module is 1/2" plywood attached to 1x4" framework, as with regular modules. Widths and lengths of mating faces can very between the limits shown. Legs are attached as with standard modules, at the noted locations. (e)

  1. The front edge is 33" long, 32 1/2" with an outside passing track.

  2. The rear edge is 32" long, 25 1/2" if the 30" width is used.

  3. Corner braces are 2x2" blocks, 3 1/2" long.

  4. All frame members are standard 1x4", lengths as required.

  5. Locations of leg attachments.

Figure 7 - Corner module track specifications

Sample 4' square corner module

  1. The light line shows a greater width module (25" instead of 24") which is to be used whenever the outside passing track is to be applied.

  2. These small sections of straight track just after the spanner tracks produce needed spacing between curves and help prevent kinks between the spanners and the module's trackage.

  3. The inside and outside passing tracks are optional.

  4. These are the standard spanner track gaps.