The Bodgeller's Uncoupler and Point Changer

 

To explain, a bodgeller is one like myself who is halfway between a bodger and a modeller. If you are one of those who mills spigot flanges from brass bar with your bare teeth, look away immediately. The same advice applies to those who are ready to spend the odd hundred quid or so on equipment from LGB or other manufacturers. I guarantee, however, that the methods I lay out here work, and work exceedingly cheaply.

 

Uncoupling

This is a method of automatic uncoupling I have developed using fixed magnets, 6BA steel nuts (metric will do), and florist's wire (a very useful bodging material, which may well make the paperclip obsolete). Unfortunately, I found no use for my sticky-backed plastic, and my Fairy Liquid container is still three-quarters full, but I live in hope. The cost is about four quid per magnet (one for each siding), and about nothing per vehicle.

I use LGB and Playmobil couplings interspersed with Brandbright's loop buffers, which are perfectly compatible when mounted at the right height. The fixed magnets are Eclipse Magnetics' small 3/4" diameter button magnets (part no. EM822-R). These have a groove separating the North and South poles, which makes them perfect for aligning to the top surface of the sleepers to ensure a constant distance below the rail tops.

Whoever said a picture is worth a thousand words obviously hadn't seen my draughtsmanship, but here goes!

I use LGB track, whose sleepers are deeper than the groove width (about 6mm), so I chop a small slot in the BOTTOM of one face of the sleeper to give a tight fit for the magnet, thusly:

(I told you I couldn't draw).

The sleeper and magnet fit together snugly like a mortise and tenon joint, and the magnet is held tightly with its top a known distance below the rails.

Now to deal with the stock. I use a shunter's wagon based on an LGB Feldbahn (Light Railway) chassis as a link between my locos and their trains (it also holds Radio Control and power circuitry, but that's another story. I simply drill the smallest possible hole in the aft coupling hook and sling a 6BA bolt a couple of millimetres below the hook.

 

In my early trials, this worked reasonably well, but the alignment of vehicle over magnet had to be well-nigh perfect for the magnet to pull the hook down against the tough little plastic return spring. In seeking to weaken the spring, I broke it, and then enlightenment struck. Playmobil couplings are very similar to LGB, but they use a counterweight to level the hook. I glued two 2BA nuts on to the "horns" of the non-business end of the hook and Bob was my uncle.

 

The resulting arrangement is every bit as reliable as the original spring when pulling a train, but now the uncoupling is much easier. To uncouple one simply backs the train until the nut is over the magnet and pulls the loco and shunter's truck forward away from its train. It is much more forgiving in terms of positioning, and it is now easy to do so from my throne some five yards from the sidings. A blob of white paint (16mm seagull droppings, if anyone asks) on the appropriate sleeper helps when lining up the loco. With practice, fly shunting is quite possible, and uncoupling is as easy with my R/C "Katie" as with my Playmobil-powered Fowler diesel.

It has not escaped the attention of the author that only minimal expense and effort is involved in converting the couplers on other stock to use this system. Although my original intention was just to fit the shunter's wagon, this will duly be done for all stock not forming the middle of a fixed consist. It simply involves removing the hook from the Beaufort end of the coupling and doing the above operations to that at the Pigsty Hill end. (I have no reversing loop, and I suspect that might cause complications - the solution is left as an exercise for the reader).

If one was starting from scratch, the Brandbright loop coupling with a fabricated hook would be an obvious starting point, although I believe the LGB assembly is available as a spare part.

 

Pictures of the Finished Article

 

 

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Point Changing

 

I have set up the line for remote point changing and station lighting, using the track to carry the DC switching and lighting current, for a total cost of about £15, as shown below:

 

The point changing gear consists of a doorbell switch wired to a DPDT slide switch, to which it is attached with black electrical tape. (A picture of this monstrosity will be found below). Two lengths of surplus mains cable are used to connect this to two flat-pin connectors. One of these plugs into a spur off the cable linking the two point motors (24V garden lighting cable). The other plugs into a lead from the track, which carries the lighting voltage. Much WD40 is applied to these connectors, which will live outside.

To change the points, the desired route is chosen with the slide switch, and the doorbell pushed. (N.B. Never use a plain changeover switch for this, sure as eggs is eggs something will distract you in mid-throw and you'll burn out your point motors).

Incidentally, you'll notice that I change both my points at once, for sidings at opposite ends of the line. Very simple, and I'd like to hear one good reason why I shouldn't.

 

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