sizes

[84engineers]

being new to the trains ,have a very novice question.what are people talking about when the say,is your track a 83 or 100?

[Hunt]

Track Code is the height of the rail in thousands of an inch.
Code 100 – 0.100"
Code 83 – 0.083"

Bachmann HO track rail is Code 100.

[ebtnut]

To be a bit more expansive, Code 100 rail was the common standard for HO for decades.  Smaller rail sizes, such as Code 83, 70, and 55 came about as modelers looked to have rail sizes more in keeping with typical scale track.  In HO, code 100 represents prototype rail of about 156 pounds/yard, the heavist ever made.  Only the Pennsylvania RR used this rail and only on the most heavily-used portions of their main line.  Back in the steam era, main line rail usually ranged in the 100-125 pound range.  Code 70 rail is equivalent to 100 pound rail, and Code 83 is about 132 pound rail.  Code 55 rail equates to about 75 pound rail, very typical for yards, sidings and short lines.  Today, you can get flex track and turnouts for code 100, 83, and 70 fairly readily.  A beginner should start with code 100 just becuase it is most common and comes with most train sets.