NEM sockets are the European standard pocket for swappable couplers on HO/OO
rolling stock. Not sure if there is an N gauge or even an O gauge
Most rolling stock from Bachmann now has NEM sockets, and Hornby are
beginning to implement the same. This means that eventually, you will be
able to buy whatever item of stock (loco, coach, wagon) and change the
couplings to suit. However, note that Bachmann's implementation of the NEM
socket frequently does NOT meet the NEM specification for height, so you
have to be careful when selecting couplings for them (for instance, using
NEM Kadees from the US, if you fit them to a Standard 4 tank, the coupling
at the front will be at a different height to the one at the back! In this
situation, some ingenious modification is required!)
Phil: An international, multi-manufacturer 'common standard' coupling
CONNECTION - especially important on 'the Continent' where the strong
brands of Fleischmann, Marklin, Roco etc have ALL designed their own
proprietory couplings as improvements over the 2 basic styles in use 'by
default' over there. ANd obviously users would wish to standardise on
their own preference.
Instead of each coupling design having unique and incompatible connection
points**, they have a comon design 'pocket' connector, which SHOULD be
mounted at a 'common' height, so any coupling design using the NEM pocket
connector will automatically be in the correct place (height and length). **Eg The traditioanl Triang-Hornby coupler has a choice of 3 screw/rivet
positions. Airfix made a 'plug-in' type of connector, and 3 different
generations of couplers plug into these (and easy to convert to Kadee)
The NEM pocket is a small rectangular 'tube' about 2-3mm high x 4mm wide x
8mm long (from memory -not actually measured by me as I write). It should
be approximately at the same height as a TRIANGtype coupling.
Therefore a NEM KADEE coupler has a bar (which plugs in to the pocket) and
a HEAD which is ABOVE the height of THAT bar - to get the centre of the
head about 10mm from the rail (10.5mm according to a more accurate
An important operational point to note is that the connector is/should be
mounted so as to be able to MOVE sideways assisting cornering by letting
the coupling stay nearer the centre of the track.
So a 'European' modeller might choose to fit the Fleischmann 'Profi' close
coupler to all their stock - and simply unlug the old, and plug in the
new: plug and play!
Equally, I might expect to remove a NEM pocket coupler, and find that a
Kadee No17,18,19, or 20 (different lengths of NEM connection KADEE coupler
(- the longer No20 being needed in most cases to clear buffers on UK
All the HORNBY and HELJAN NEM pockets I have measured appear to be correct
in height, but the BACHMANN vary considerably - too much to interconnect!!
(And yes, Kim, that should have read Class 37 not 27 - a tryping eroorr8-)
Bachmann obviously realise they have a problem in that they make 2
versions of their NEM- Triang/hornby style coupler - with and without a
vertical offset! - by definition it should only need 1 type (height) if
the NEM pocket is in the correct position.
I have passed by earlier posting onto my Bachmann dealer, for him to
forward to Bachmann for comment.
hiope this description has helped; Summary:
NEM pocket - a standard way of plugging in your design of coupling
NEM-pocket couplings are therefore available in many actual coupling
designs, but should be interchangable across manufacturers.
As standard as 12V dc or dcc.
No clear ideas from me as yet. I haven't even attempted conversions to such
However, I normally address the Kadee conversion on carriages by mounting
them directly to the body of the vehicle, as against using the NEM pocket on
the bogie. This allows me to set the height using a Kadee height gauge
(meaning the stock has the same coupling position as American HO stock,
which is not to everyone's tastes). On wagons with the NEM pocket on the
underfloor of the wagon, if it is correct for the Kadee height gauge, then I
just put the NEM Kadees in straight. If too high, I cut off the NEM pocket
and using thin plasticard in layers to lower it and use NEM Kadees, or I
remove the NEM pocket in its entirety and replace it with a Kadee No5.
As for the NEM Kadee conversion, I believe some kind of adjustment to the
coupler itself, in the form of raising or lowering the knuckle in relation
to the NEM 'tails' might be possible, but I've not tried it yet, so can't
vouch for it as an effective method.
I think that the NEM arrangements for couplers are called 'pockets', to
avoid confusion with the electrical connection 'Sockets'.But I haven't
looked at the German word for the coupler arrangement to see what the
English translation of it is. It may be pocket or socket or something else.
Also, Kadee couplers can be got with various vertical offsets which
should cover most of the pocket height variations.
I reckon that, with a few exceptions, Bachmann NEM pockets are generally
one of two heights, corresponding to the two different Bachmann coupler
types. On some vehicles - mainly wagons- where the pockets are detachable,
I lower them using small pieces of plasticard as packing. I normally use
Kadee #17-#20 couplers. Occasionally I use a #20 cut in half behind the
head and then glued and pinned together again with an offset to lower the
head. On other vehicles I have used spare NEM pockets mounted on a
platicard block glued to the underside of the chassis.
To pick up on (Keith's) comments about the Kadee coupler on the 'modern
Bachmann wagons' which he suggests is in the prototypical position for the
original's buckeye coupler....(it may be, but..)
1/ The Kadee coupler is a proprietory standard, (and the Bachmann EZ Mk2
coupler claims compatibility with it) with specifications for 16.5mm gauge
(regardless of scale - see below) about how far the magnetic wire needs to
be off the ground for uncoupling to work, and the the coupler head to
achieve coupling (the very purpose of a coupler)
2/ It is NOT an OO or HO scale buckeye - it may look a bit like one, but
is oversize and adapted to meet the practical needs of working on a MODEL
railway. Like other model couplings before it, it is located to ensure
flexibility in operation, without interfering with its projections etc.
3/ Your suggestion that it is there as a representation of the original
buckeye does not account for the drop wire which is not a feature of the
original - and its not getting close to the magnets!) - If they want a
scale buckeye - by all means mount one in the correct poition, above the
4/ It does not answer the observation of their being inconsistant with the
position (height of the NEM pocket - which again is specified for 16.5mm
gauge - especially on the same locomotive (front and back)
(Please note that those 'overseas' are not interested in the UK hobby's
petty internal rivet counting squabbles over distinctions like OO EM or
P4.: 16.5mm gauge is a common standard on which OO and HO stock should
run and be able to couple.
There will (overseas) only therefore be ONE set of standards - especially
since the use of the term OO in the USA has a different meaning!!.
5/Other manufacturers do not appear to be having difficulty placing it in
a consistant position.
If they wish to continue making incompatible products - can they please
stop attaching 'implied compatibility' labels - or do we need to get
Trading Standards to investigate misleading claims in the lucrative model
Not regardless of scale, the standards for coupler height that KADEE
follow are NMRA standards for H0. I can't see where you have given any
references below? The standards are at but
since they are standards designed to allow interchange of US prototype
models on the scales as specified its all irrelevant to those of us
modelling UK practice to 4mm scale, if we decide to make use of KDs we
can use them as we see fit.
If those of you mixing all kinds of trains that run on different
continents in the real world, modelled to different scales, and want
them all to couple together, you can also use them as you see fit.
But your usage does not somehow make NMRA and NEM standards for US or
European H0 trains become mandatory for UK models to 4mm scale of
whatever gauge. Hence it is illogical to claim that any particular
version is WRONG. Criticise them for their inconsistency, certainly.
This is uk.rmr, those overseas are not under discussion unless
interested in UK practice.
For H0 there are several standards, those of the NMRA and the NEM
being the most prominent, there are others such as AMRA. There is no
such generally accepted standard for UK 00, although the 00 gauge
association has tried.
I see no reason why they should be able to couple as 00 and H0 are
different scales and unless you distort one or the other neither the
buffers nor the couplers will match. They should never appear in the
I would agree that since NEM started to adopt finer standards the NMRA
and NEM are converging, there is some way to go before there is only
But its all irrelevant to UK 4mm, we have P4 standards and EM
standards and the 00 crowd do whatever they like, call it Pick and
Make friends in the hobby.
Garratt photos for the big steam lovers.