HO scale track

[rmcculla]

Hi Everybody;

I was wondering what track "code" pertains to.

Thanks, Bob

[rbryce1]

Track code is rail height in thousandths of an inch.
Code 100 (.100")
Code 83 (.083")
Code 70 (.070")
Bachmann HO track is code 100

Imagine from Model Railroader Magazine

From the illustration, it seems the code variations are not only in height, but also in width at the base.  Does a conversion rail joiner also have a width change in addition to the height adjustment to go from Code 83 to Code 100, or do they just use the Code 100 joiner width for both sections?

[jward]

there is no change in width in transition joiners. most rail joiners are designed to hold the rail web (the narrow part between the head and base) in alignment. usually, lateral alignment is more critical than verticle alignment.

[rmcculla]

Thanks for the reply's!

One more question, if you please.
I see that Bachmann HO scale track is code 100 and I'm sure that this choice is NOT by whim. What are the advantages of this code to the user?

Best regards, Bob

[jward]

code 100 was the traditional size of HO rail. ez track is a holdover from those days. code 100 is stronger than smaller sizes, but it is oversize. as a result, many of us prefer to work with codes 83 and 70 which more accurately represent real railroad track. the smaller sizes are more fragile.

[Doneldon]

I see that Bachmann HO scale track is code 100 and I'm sure that this choice is NOT by whim. What are the advantages of this code to the user?

Bob-

Code 100 rail is a little more durable due to its beefiness compared to smaller rail. It also helps to keep oversized flanges from contacting the ties and derailing. That's not much of an issue any more because virtually everything has either RP25 wheels or some level of scale wheels with shorter flanges. However, Code 100 would be best if you run a lot of older models with huge flanges. Frankly, I'd prefer to change wheel sets to running oversize rail but that's just my personal opinion.

Oh, yes. One more advantage: Code 100 comes with most train sets so it can be used without added expense.

                                                                                                                                                                       -- D

[ebtnut]

Just by way of history, Code 100 rail was the "standard" for HO trains from at least the 1940's through the 1950's.  Any commercial track you bought, flex, Snap, Tru-Scale, etc. was Code 100.  Scaled down from the prototype, code 100 represents approximately 156 pound rail, the heaviest rail ever used.  Most railroads used main line rails in the 125 - 140 pound range into the late steam-early diesel period.  Secondary lines, branches and yards used lighter rail.  It was desire to represent these various rail weights that generated the market for a larger selection of rail codes.  Code 83 represents about 136 pound rail for main lines; Code 70 for 100 pound rail; and Code 55 for about 65 pound rail.  All of these rail sizes can be used with RP-25 wheels, though with code 55 you have to be careful if handlaying to use very thin head spikes.  Note also that the rail codes go up, too.  Traditionally, S scale used Code 125 and O scale Code 172.  For the Magna-Visor bunch, there is also Code 40, which scales out to 40 pound rail in HO, but is a good scale size for N scale models.  However, if you hand-lay it, you have to glue it down.