Atlas code 55 N scale track.

As the placing of track continues apace on my N scale MRL layout, it occurred to me how modellers in the US appear to make life easier for themselves in many aspects of the hobby, from baseboard (bench work) to wiring techniques. This includes their expectation of the products they buy. Take the turnouts from the Atlas code 55 trackage range, for example. The crossing vee (frog) is cast metal and insulated from the rest of the rails. It is very nicely done too, with a metal connector from the vee to a solder point by one of the sleepers which means it can be easily wired to a polarity change switch, say like one of those incorporated in a Tortoise point motor.

The stretcher bar extends to both sides of the switch offering the modeller the choice of left or right hand throw position to suit the track formation – the unwanted one is carefully trimmed off.  Also, the stock rail and switch rails are bonded so there is no need for electrical power routing via metal tags on the switch rails. Much more reliable that way.

The electrical characterisitcs of the turnouts became apparent when I first applied power to the first track formations I laid on the layout. With an insulated crossing vee AND reliable electrical connections beyond the vee between the diverging rails, any amount of complex track geometry could be powered from one point. As a bonus, and completely against the grain of everything I have done before – my big US diesels nicely bridged that crossing vee without a hiccup – do I need to power the frogs? I should really, just for good practice.

As I state in my DCC book, good wiring practice is good wiring practice, no matter what power source you use, be it analogue or DCC. Nonetheless, using turnouts straight from the packaging without having to do a Peco ‘Electrofrog’ reliability upgrade for reliable power supply is a huge relief. I don’t like the term DCC-friendly turnouts because there’s no such thing, but the Atlas code 55 ones are pretty perfect in this regard.

It should be remembered that nickel silver rail has a relatively high current resistance compared to copper wire and rail joiners can fail or cause unwanted voltage drop together with degradation of the digital signal. The ability of the DCC booster to detect short circuits depends on good contacts and current supply, so don’t rely on the rail to carry the current for long distances. I am now in the process of adding power dropper wires to each rail for as reliable power supply as can be achieved. This is good practice for both analogue and DCC control systems.

British outline and Atlas code 55 track:
It’s worth noting that wheel back-to-back measurements on British N gauge models is slightly different to that of US outline stock. It is slightly less which means that it will find the flange ways through Atlas code 55 track a little tight. Bearing in mind that this track is designed for US prototypes together with the correct sleeper spacing and scaled for 1:160 proportion, UK outline N gauge models still look quite good on it. Only modern Graham Farish will cope with the fine rail section without running on the rail clips (spikes).

I ease the back to back measurements on my UK outline models out slightly and they run through the track perfectly as a result. This does not affect their ability to negotiate Peco N gauge track at all. To help things along, I took a British N gauge back-to-back gauge and added a piece of 10thou styrene to it to obtain a slightly wider measurement. It has been successful and the electrical power features of this track makes it all worth while.

Now do I power the crossing vees or take the chance that they will be okay?


Leave a Reply

Please log in using one of these methods to post your comment: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s

%d bloggers like this: