High rail vs Scale?

why did MTH do this?

To offer model railroaders a choice. For the past several years, MTH has made many of their engines in both high-rail and scale models.

Engines with product numbers ending in -1 are intended to be run on high-rail 3-rail track and have bigger flanges. Diesels with a -1 also have swinging pilots. The smallest curve on which these engines can negotiate is indicated as the diameter of the circle.

Engines with product numbers ending in -2 are intended to be run on scale 2-rail track and have smaller, scale-sized flanges. Diesels with a -2 also have fixed pilots. The smallest curve on which these engines can negotiate is indicated as the radius of the circle.

On diesels, wheel sets are available for changing the nature of the flange to make it larger or smaller.

Thanks BARRY, I figured you would know.  Thanks again.

laz57

Don't forget the -3 for non powered units. 

laz

The T1 steamer that you have would require a much larger radius than 36" This is because they have a much stiffer frame and small scale flanges that do not work well on fastracks rounded rail.  If it was a diesel it could easily be converted to 3RS (what I run) the -2 denotes scale wheels and fixed pilots.  I run fixed pilots on 3 rail track by exchanging the scale wheels for Hi rail wheels.

The catalog description for that T-1 says high rail wheels operate on O-42.  It says scale wheels operate on 54" radius (O-108)!! 

You need to take that pig back and swap for a high rail version, pronto! 

The scale version diesels require no conversion, as they come with fixed pilots and scale wheels.  Just install the Kadees and you're in the club.  

If you run pizza cutters, can you really call yourself 3RS?   Pizza cutters equals high rail.   We would need to call that one high rail scale(HRS).      All we need is another category. 

hmmm, but if the definition of slop is "to pass beyond or exceed a boundary or limit" (as in a locomotive altered to navigate unrealistically sharp curves), i'd think the high rail version would be more closely related to the porcine family.

Thanks GUYZ,I am getting a hi rail pilot put on everything else works great.

YES!  3RS does NOT require that you run RP25 wheels.  As many of us in 3RS have noted it can be done, but it is neither required nor even recommended to qualify as 3RS.  In many cases, using RP25 wheels on 3RS layouts reduces reliability.  It is standard practice in 3RS to purchase "-2" MTH diesels and swap out the wheel sets for hi-rail.  Otherwise it's just a 2-rail engine with 2-rail/3-rail switch thrown.

Exactly what Dave said.  While scale wheels do work on the 3 rail track that most of us use it is not te best for operation.  The frogs on 3 rail are cut so low and wide that scale wheels cause locos and cars to bounce around while going through.