G scale Sectional Track or how I learned to stop worrying and love the bomb.

 

It is indeed that crazy! (reference the Stanly Kubrick movie)

Initially LGB, the pioneer, came up with a system that used "R" numbers for sectional track. It was never great, parallel track spacing would not always work for longer cars, some "R" numbers were missing (the almost vaporware R4), etc.

Then other companies picked up the nomenclature, but used different numbers.

Below is a "lookup" table to help you decode what "R" number from what manufacturer is, it is a real mess.

Note, the numbers below are APPROXIMATE, not exact, there is variation between manufacturers. Check the exact numbers on the manufacturer's site.

Pick your R number

Given an "R" number AND a manufacturer, what is the radius/diameter

 

"R"
  number  

  LGB
  diameter  
feet

Piko
  diameter 
feet

Train-Li
  diameter 
feet
  Train Line 45 
diameter
feet
 

LGB
  radius  
feet

Piko
  radius 
feet
  Train-Li  
radius
feet
  Train Line 45 
radius
feet
 R1 4'4'   2' 2'  
 R2 5'  6'  2-1/2'  3'
 R3 8'6'6'8'  4'3'3'4'
 R4~11-1/2'  8'   5-3/4' 4' 
 R5 15'8'    7-1/2' 4'  
R6         
R7 10-1/4'    5'+  

 

 

Pick your diameter/radius

Given a target diameter/radius, who makes what and what is it called:

 

 Diameter 

Feet 

 Radius 

Feet

  LGB 

  Piko  Train-Li   Train Line 45 

Aristo Craft 

USA Trains
42R1R1  4'4'
52-1/2 R2   5' 5'
63 R3R3R2  
6-1/2~3-1/4    6.5' 
84R3R5 R4 R38' 8'
94-1/2    9' 
10  5     10' 10'
10-1/4 ~5 R7    
11-1/2~5-1/2 R4   11.5' 
12-1/26-1/4    12.5' 
147    14' 
157-1/2R5   15' 
168     16'
16.5~8-1/4    16.5' 
2010    20'20'

 

Link to Piko track planning guide:

https://cdn.shopify.com/s/files/1/1960/4221/files/99350_G-Track_Flyer.pdf?9757276037842777937

 

Link to LGB track planning guide:

https://www.lgb.com/fileadmin/media/lgb/produkte/produktinformationen/LGB_Gleissystem-Info.pdf

 

Notes:

  • There is no R4 curved track from LGB
  • There is no even numbered curved tracks from Piko

What a mess huh?

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