Tomix TN Couplers

Rapido coupler. Looks awful, but it is one of the most reliable couplers ever designed.

The Rapido coupler is the standard for N-scale trains, and has been for some 30 years. Rapidos are easy to couple together (even if they take some fiddling to uncouple), and they hold together reliably over a wide range of conditions, pushing and pulling, up inclines and at funny angles. But they are ugly, and they are huge. Most modelers in North America opt for the Micro-Trains Magne-Matic coupler, which not only looks better, but offers semi-automatic uncoupling which uses track-mounted magnets instead of hand-held toothpicks to work. (The N-Scale Division has a great history of n-gauge couplers.)

TN truck-mount knuckle coupler

The Magne-Matics are great for switching cars, but aren’t as reliable as the Rapido for semi-permanent consists, which is how most Japanese trains run. The most popular alternative to the Rapido in Japan is Tomix’s TN coupler system. The TN comes in two varieties, knuckle couplers—most commonly used on freight and passenger cars—, and Scharfenberg couplers, most commonly used on EMUs and DMUs.

TN truck-mount Scharfenberg coupler

TN couplers are available in black, and in gray; they are also available as truck-mount and body-mount. There are a very wide variety of body-mount versions, some designed for specific models, and some designed to be more universal. Check your model’s instruction sheet to see which coupler it takes.

In general, TN couplers are very reliable. Since they are designed for semi-permanent coupling, they hold amazingly well, but come apart with just a gentle tug when you want them to decouple. Because they decouple by pulling apart, I doubt that they would hold up for very long trains, but they are stellar for the 2–15 car consists common in passenger service in Japan. Naturally, TN couplers are an inappropriate choice for shunting work.

TN body-mount Scharfenberg coupler

Models must be designed to accept TN couplers. Most models will offer mounting tabs in the body. Some models only offer the option of swapping out the standard truck-mounted Rapidos for truck-mounted TNs, but even these can look very good (certainly better than what they will be replacing!). Kato models do not offer any provision for fitting TN couplers, and thus conversion to TN can be incredibly difficult as a result.

Micro Ace has designed a line of couplers that use a similar-looking but incompatible coupling system. However, as they use the same mounting system as TN body-mount couplers, Micro Ace models designed to take Micro Ace couplers can be fitted alternately with TN couplers instead. In general, TN couplers provide a closer coupling than do the Micro Ace couplers, and so should be preferred. (Comparative reviews: one, and another.) Since Mirco Ace isn’t going to tell you which Tomix couplers are compatible with their models, the table below will show you which couplers to purchase given a Micro Ace part no. Both the Micro Ace and the Tomix part numbers below are for 6-coupler sets; Tomix TN couplers are also available in single pairs.

In upcoming articles, I will discuss specific TN installations; all simply snap in, but sometimes it can be difficult to make it work just right.