Standards At A Glance
Layout Theme: Branchline
Layout Type: Modular Layout
Size: Straight 16.5"x48", Corners 30"x30"
Scale: HO Scale
Track: Code 83
Turnouts: No. 5
Min. Radius: 24"
Article by: Jim Spavins
Published: March 1, 2016
Last Updated: March 1, 2016
This module standard applies to all modules used in the HO scale BranchTRAK system. This standard is subdivided into definitions, train control, benchwork, trackwork, and electrical sections. This standard is applicable to modules upon which construction has not begun at the time that the standard is adopted. It is recommended but not required that old modules be retrofitted to this standard.
This standard is based on three fundamental principles. First, creativity in module design and construction is encouraged. Second, mainline trackage will be designed and operated to optimize the continuous running of trains on the mainline. Third, the design, construction, and operation of trackage other than the mainline trackage is at the complete discretion of the module builder.
BranchTRAK Definitions. | Drawn by Jim Spavins.
2.1 Module: The minimum unit into which the railroad may be disassembled.
2.2 Module Group: The minimum unit in which the railroad may be operated. A module group may consist of 2 or more modules which cannot be operated without all the modules in the set.
2.3 Directions: Left and right when used in this standard refer to the directions on the module when viewed from the front of the modules. Front refers to that side of the module closest to the spectators of the layout.
2.4 Main Line Trackage: The one continuous track required on each module.
2.5 Non Main Line Trackage: All trackage other than main line trackage.
2.6 Bridge Track: Three (3) inch sectional tracks which are temporarily installed between two adjacent modules for the purpose of connecting main line trackage.
3.0 TRAIN CONTROL
3.1 Mainline Control: Control of trains on mainline tracks will be through the use of digital command control (DCC) using a system supplied by the club.
4.1 Connecting Modules: Module groups will be connected with draw latches. National Hardware Brass Draw Catches (Part Number V1842) are recommended.
4.2 Height: The height of the roadbed will be 5" from the table top. No deviation shall be permitted.
4.3 Height Adjustment: Module height shall be adjustable from +/- 0.5" from the 5" above the table top. If bolts and t-nuts inserted into the ends of the modules are used for height adjustments, the bolts shall be at least 1.5" x 1/4-20.
4.4 Length: All straight modules shall be forty eight (48) inches in length. No deviation shall be permitted.
4.5 Width: The width of a module shall be 16.5". No deviation shall be permitted.
4.6 Materials: Materials shall be selected to make modules which are sufficiently flat, strong, and stable to permit trains to run without derailing or uncoupling.
4.7 Depth: The depth of the modules from the railhead to the bottom of the end framing shall be 4 inches.
4.8 Color: Benchwork shall be painted a dark green.
BranchTRAK Trackwork Guidelines. | Drawn by Jim Spavins.
5.1 Trackage: Trackage shall be code 83 nickel silver commercial flextrak. Grades and/or super elevation (banking) are not permitted.
5.2 Track Spacing and Setbacks: There shall be one mainline track. Within three (3) inches of the end of a module group, track shall be straight. Tracks shall end between 1-17/32 and 1-9/16 inches from the end of each module group. The centerline of the mainline shall be set back from the front of the module 4.5 inches.
5.3 Track Curvature: The minimum required radius of curvature is twenty-four (24") inches.
5.4 Turnouts: It is recommended that Number 5 or larger turnouts be used on the mainlines.
5.5 Turnout Size: When the diverging route in a turnout is used as mainline, turnouts shall be #6 or larger.
5.6 Insulated Rail Joiners, Use: The use of insulated rail joiners is required where electrical isolation is needed; air gaps are not permitted. Insulated rail joiners shall be used where necessary to prevent electrical short circuits.
5.7 Electrical Blocks: It is recommended that provisions to turn on/off all non mainline trackage be included on the module.
BranchTRAK Electrical Diagram. | Drawing by Jim Spavins.
6.1 Track Voltage Service: Each module shall have electrical service to transmit track voltage to the next module as well as mainline trackage. Breaks in these conductors shall be minimized. Where broken, the conductors shall be joined with a plug, e.g. section 6.3, or a solder joint.
6.2 Track Voltage Service, Plugs: Plugs (male and female) shall be 2-Pin Nylon XT60 Connectors. The color shall be black. The point side of the plug shall connect to the black wire (outer rail) and the square side shall connect to the white wire (inner rail).
6.3 Track Voltage Service, Wiring Size: Wiring for the transmission of power between modules shall be of at least 14 gauge. Wiring for local use within a module shall be of at least 20 gauge.
6.4 Track Voltage Service, Wiring Color, and Connector Configuration: Female plugs shall be installed on the left side of the module within 6 to 12 inches of the end of the benchwork. Male plugs will extend 12 inches beyond the right end of the module. Wire colors and configurations shall be as follows:
Main line track, outer rail: Wire Color - Black
Main line track, inner rail: Wire Color - White
Local tracks, outer rail: Wire Color - Black
Local tracks, inner rail: Wire Color - White
6.5 Accessory DC Power Service: Each module shall have electrical service to transmit +/12V DC accessory voltage for use to power accessories such as switch machines and lights. Breaks in these conductors shall be minimized. Where broken, the conductors shall be joined with a plug, e.g. section 6.6, or a solder joint.
6.6 Accessory DC Power Service, Plugs: Plugs (male and female) shall be 2-Pin Nylon XT60 Connectors. The color shall be yellow. The point side of the plug shall connect to the purple wire (DC +) and the square side shall connect to the orange wire (DC Ground).
6.7 Accessory DC Power Service, Wiring Size: Wiring for the transmission of power between modules shall be of at least 18 gauge. Wiring for local use within a module shall be of at least 20 gauge.
6.8 Accessory DC Power Service, Wire Color, and Connector Configuration: Female plugs shall be installed on the right side of the module within 6 to 12 inches of the end of the benchwork. Male plugs will extend 12 inches beyond the left end of the module. Wire colors and configurations shall be as follows:
Accessory DC (+): Wire Color - Purple
Accessory DC (Ground): Wire Color - Orange
7.1 Scenery at Ends: All scenery at the ends of a module group shall slope down so as to create a flat profile at a level 0.25" below the main line tracks.
7.2 Track Weathering: All trackage on the modules shall be weathered using flat color paint.
7.3 Backdrop: A backdrop shall be affixed to the back of the module which extends 10" above the module frame.
8.0 ROLLING STOCK AND EQUIPMENT
8.1 Maximum Length: Any piece of rolling stock or locomotive to be operated on the layout shall be no longer than ninety (90) scale feet, excluding couplers.
8.2 Maximum Train Length: Any trains operated on the layout shall be no longer than twenty (20) cars + two (2) locomotives + one (1) caboose.
8.3 Locomotive Numbering: All locomotives shall be equipped with a DCC decoder and programmed with a club assigned number. It is recommended that the speed steps be set to 128.
8.4 Weight: All rolling stock shall be weighted based on the following formula: 1 oz plus 1 oz for every inch of the piece of rolling stock.
8.5 Couplers: Metal knuckle couplers (such as Kadee No. 5's) shall be installed on all equipment.
These are not required - just a few ideas which have proven beneficial to past module builders.
Mainline Trackage: It is recommended that a short section of tangent track be provided after the 1.5" setback before any curves or turnouts. In addition, S curves should be designed to allow a minimum 10" tangent stretch of track between the changes in direction of the two adjacent curves. Turnouts should be placed so that the mainline is not routed through the divergent route of the turnout.
Scenery: It is recommended scenic elements on the module be designed so as to minimize the transition between modules. This means that roads and waterways should be aligned to leave the module at the front and back rather than at the ends of the modules. Topographic features should also be designed so that hills or mountains roll back down to the mainline track level by the ends of the module.