Consistent coupler height is a must when running trains outdoors over less than perfect track work. While many people use Hook N Loop couplers, which eliminate many uncoupling problems, there is a large group of us that use Bachmann, LGB, USA, Aristo, Accucraft or Kadee knuckle couplers on our trains. With any of these knuckle couplers, height consistency is critical to smooth train operation without uncoupling.

My first suggestion is to choose a coupler type and standardize your entire fleet along with your locomotives. USA and Aristo knuckles seem to work well with each other, and Kadee will also couple with them. I usually replace LGB and Bachmann couplers with Kadee to simplify operation since those two do not like to mate with any other coupler than their same brands. My goal is to someday have all Kadees to make switching more realistic.

Once you have decided on a coupler brand, it is necessary to find and use a coupler height gauge. Kadee makes an excellent coupler height gauge which I use extensively when working on my rolling stock. The gauge costs around $17.95 and actually has five different uses. 1-Provides instant visual reference of proper coupler height. 2-Gauges car underbody height from rail. 3-Gauges track width. 4-Gauges wheel width. 5-Use as an uncoupler gluing jig. It is available for both "G" and #1 Kadee couplers. It can also be modified (See Vance Bass article in GR February 2008) so that it can be used with 1:20.3 Accucraft or 1:20.3 Bachmann couplers. For 1/29 gauge he recommends raising the gauge 5/64" and for 1:20.3 he recommends 5/32". Shims for these additional heights can easily be made out of styrene or wood.

Once all your coupler heights have been standardized, you should experience trouble free railroading.