Inglenook Kadee Magnet Placement Advice

Many of us, especially those of us with a shelf switching layout, have an Inglenook. Kadee magnet auto-coupling/decoupling makes operating an Inglenook much easier (when it works) but is a real pain when it doesn't, or if the magnets are put in the wrong place.


First off, what exactly is an Inglenook? Figure 1 shows the basic layout (adapted, with many thanks, from the Model Railways Shunting Puzzle Web Site) and can be adapted to any scale, with a couple of points (switches) and 7 or so bits of track.

Figure 1: Basic Inglenook

The operating fun to be had with the Inglenook relies on being able to pull wagons off trains (rakes) which are parked on the ends of the Inglenook, and swapping them with others, in a kind of Towers of Hanoi style puzzle.


While decoupling using the paintbrush-with-a-loop-of-wire-on-the-end solution is all well and good, for the ultimate in operating action, many enthusiasts like to implement some kind of automatic decoupling solution. Kadee manufacture such a solution, using magnets and knuckle couplers to provide a reliable shunting experience.


Due to the way that they work, on an Inglebook, Kadee magnet based auto-decouplers  are a great solution for one simple reason : delayed decoupling. For layouts using electromagnetic decoupling (in my opinion, the next best thing to Kadee's solution), magnets are needed at each place where a wagon (truck) can be uncoupled.


Wagons can be uncoupled  from other wagons, or from the loco (shunter), and Figure 2 shows where the placements should be (or could be) for an Inglenook using only electromagnetic automatic decoupling.

Figure 2: Inglenook Magnet Placement

There are other places that magnets might be appropriate or desirable, but Figure 2 serves to illustrate the point - 3 separate magnets, with three separate buttons, are required to be able to spot trucks (wagons) on each of the three sidings of the Inglenook. 


Kadee magnet based uncoupling changes this, as seen in Figure 3.

Figure 3: Inglenook Kadee Magnet Placement

The reason only a single magnet is required is that once decoupling has been activated the remaining rake (train, or wagon) can be shunted into place, and remains decoupled. When the loco pulls away, the decoupled wagon or rake is left in place - delayed decoupling.


There is a drawback, however. In order to decouple a relatively long rake, the track in front (to the left of) the magnet needs to be long enough to accommodate it. However, if this proves to be a problem, more magnets can be added on the sidings themselves, this allowing decoupling with some, or most, of the train over the points.