Track gauges – On2

In this post we show some of the commercially produced gauges available at various times.

Simpson roller track gauge.

Russ Simpson produced these gauges to suit variety of rail sizes (eg codes 55, 70, 83 & 100). They were first announced in July 1977 and were available direct and from suppliers such as Coronado Scale Models, Caboose Hobbies and BK Enterprises.



The section below was copied from the Simpson catalog;-


Portland Products NMRA style gauge.

Bob Werner produced this style gauge back in the mid 1990’s, and examples may turn up on eBay. One was offered as recently as mid-June 2016.




We know that SRE produced a cast brass three point gauge way back in 1970’s but we don’t have a picture or two – can you help?

On2 Yahoo group member John Rogers also produced a three point gauge in the late 2000’s to early 2010’s, but again we don’t have a picture or two – can you help?

Revised 02-07-2016 and 30-07-2017.

Precision Scale Flex track

tstr10Precision Scale introduced its On2 flex track in one yard lengths in mid-1983.

The track consists of an injection moulded tie (sleeper) base strip of 21 ties of random irregular lengths with moulded spike heads holding nickel silver code 70 rails. The track gauge typically ranges between .508″ to .512″ on measured samples.


Typical rail dimensions.

The tie base material is believed to be a Delrin type polymer. The dimensions of a typical tie are: 1.279″ long x .153″ wide x .103″ thick on .406″ centres (scale : 5′ 4″ long x 7.3″ wide x 4.9″ thick on 19½” centres).


This deliberately foreshortened view of the track clearly shows the irregular tie ends. The yellow arrows show the length of one of the tie strips. The dimension from the inside edge of the bottom of the rail to the outside of the tie varies from .377″ to .419″ on one side and from .374″ to .422″ on the other.



This underneath view shows the single bars connecting adjacent ties. Experience has shown that care needs to be taken when laying this track to ensure that the ties are as perpendicular to the rail as possible, and not angled, to avoid reducing the gauge of the rails. This is especially important on curves, and when running the larger Forney type locomotives.



Fast Tracks jig built turnouts etc.

This is a temporary posting to illustrate a discussion point (excuse the pun!).

The issue is the “correct” width of tie to use. The picture below shows (from left to right)

-turnout using Clover House S scale ties (built on home made jig)

-Precision Scale flex track

-Part built turnout using a stock Fast Tracks jig (On2 #8, code 70) and Clover House S scale PCB ties, over the Fast Tracks plan of same turnout with a Fast Tracks recommended tie (PB-S-N) placed underneath.

-Fast Tracks jig with two part built turnouts using Clover House S scale PCB ties, and a Fast Tracks recommended tie.


Close-up of the part built turnout using Fast Tracks jig and Clover House S scale PCB ties, on Fast Tracks plan of turnout with a Fast Tracks recommended tie (PB-S-N) placed underneath.



Use the link on the right titled Fast Tracks to get directly to their On2 page.