Controlling Interests #12 Uncoupling revisited – Canute Road Quay

One of the most asked questions when exhibiting Canute Road Quay is about how my remote hands free uncoupling works.  Quite some while ago now I started using modified tension lock coupling in combination with electromagnets on Fisherton Sarum, see my Controlling Interests #6 post here, but I thought I would revisit it now with more of a detailed guide.

Essentially the system is a simple addition of a short piece of soft iron wire fixed to the dropper of the tension lock coupling hook, and the installation centrally between the rails of  ‘Dingham’ electromagnets, now sold by the O Gauge Guild here.  When positioned over an electromagnet, operated by a simple push to make switch on the control panel that provides the required 12v DC for the magnet to energise, that pulls down the iron wire dropper that lifts the hook for uncoupling.
It should also be noted that if required the method will also work with small fixed magnets.

To enable operation the wagons are ‘handed’ with the hooks removed from one end, as the area of the magnet can not pull down two interlocked hooks at once,  although I find all stock on any layout performs better with only one hook between vehicles.

I create by eye an ‘L’ shaped length of the soft iron wire,  the short ‘vertical’ leg, approx 4mm,  of the ‘L’ has a slight flat filed on to it to give a greater surface area to bond to the tension lock coupling hook dropper with superglue.
I shape the horizontal part of the ‘L’ , approx 10mm, with a slight curve upwards at the end to prevent it from catching on anything.

I started originally using 1mm wire but have found that 0.7mm and even 0.5mm works just as well and the thinner the wire the more discrete it is.
I find that even when exhibiting Canute Road Quay where it is positioned at almost eye level to the public, it still is not obvious to many viewers how the remote uncoupling works!

As I have sections of inset track (see here for my method of inset track)  on Canute Road Quay I also shorten the tension lock hook droppers by approximately 2mm  to allow clearance over the insert track, but if you only have standard track this is not necessary.

The Dingham’ electromagnets are complete with a small PCB with convenient solder tags, complete with multiple common return tags,  included to make wiring up easy.  The bolt of the Dingham’ electromagnet has been simply self threaded into an interference hole drilled into the baseboard below so that the end of the bolt does not quite come though the ballast or inset track (keeping it totally invisible from view), whilst firmly holding the coil in place under the board.
See picture left for an example of installation, yes I have lighting (a strip of LEDs) and also the track plan marked (simply with insulation tape) underneath the baseboard (makes for any fault finding if required at an exhibition much easier).
A simple push to make switch on the control panel provides the required 12v DC for the magnet to energise that pulls down the soft iron wire dropper that lifts the hook for uncoupling.

On Canute Road Quay I have six uncoupling locations, one to enable a coal or ash wagon to be left adjacent to the coaling stage, one at either end of the rear loop, one at the left end of the front loop and two in the very front siding. The locations are subtly marked by a mix of figures, lighter green tufts of grass and also the lifebuoy ring stand.

A quick video of the remote uncoupling  in action can be seen below.