I am just starting in railways (n gauge) and am confused about couplings.
I have seen people refer to different types, most commonly Tension Lock.
Is this the type that I have on my Graham Farish rolling stock?
I have also noticed reference to magnetic de-couplers, do these refer to
uncoupling a magnetic coupling or are they for standard ones? Sorry if
this sounds thick but I am finding it a bit of a mystery particularly as I
have installed a couple of the Peco uncouplers and found them to be
unreliable to say the least.
(If you can't laugh at life, it ain't worth living!)
On Mon, 15 Jan 2007 13:19:03 -0000, "Keith Willcocks" wrote:
Arnold Rapido I think. (but I am just thinking about starting in N as
well ! so treat what I type with some caution :) )
This is as far as I have researched so far :-
There are couplings that can be uncoupled magnetically (the couplings
themselves are not magnetic but include steel bits in them that are
pulled by a magnet or an electromagnet mounted on the baseboard.)
They are DIY replacements for the standard Rapido.
Things to Google for are Sprat & Winkle couplings, I have a link
somewhere, but not to hand at the moment, I'll be back later when I
find it, and there is another one as well which escapes me ,,,, ummm !
There is also an electromagnetically operated mechanical uncoupler,
the Peco PL25, it seems to be a rod which is pushed upwards by an
electromagnet to lift the Rapido to uncouple it. But I must be missing
something because that would need very precise positioning of the
rolling stock ??? :(
I wonder if this is the one you have or is it the SL330 simple
mechanical device ?
Thank you for posting that, I have been asking the same question in
various other places and you are the first person to report on actual
MicroTrains, that is one I was trying to think of ( thanks Wolf !)
It is the N equivalent of the Kaydee coupler which you may also have
seen mentioned, it is much favoured in the US and gets good reports,
The other magnetically operated one is is the Alex Jackson, DIY with
springy wire :-
and the Sprat&Winkle can be found here :-
The most common couplings are:
a) the "Rapido", invented by Arnold. It couples by the jaws sliding over
each other and dropping into place. A pin underneath is pushed up by an
uncoupling ramp, which disengages the couplers. Originally, Arnold
licensed the use of this coupler, now its patent has expired. This is
the "standard" coupler to which you refer, and as you have discovered
it's not worth a rat's back end. One reason: the couplers are not made
to a uniform standard.
b) the knuckle coupler, made by Micro-Trains, which looks like a Buckeye
coupler, and works on the same principle: the jaw opens sideways when
coupling or uncoupling. It has a curved steel pin projecting underneath,
which looks vaguely like air-brake hoses. A magnet between or under the
rails pulls the jaws sideways, which disengages the couplers.
Micro-Trains' patent on this coupler is still valid, so there are no
clones available (as there are for HO/OO, since Kadee's patent ran out.)
The Accumate coupler avoids the patent issue by using a different
mechanical principle, but otherwise is compatible with Micro-Trains
coupler. The knuckle coupler is quite reliable compared to the Rapido,
but reliable coupling and uncoupling in N is much more of a problem than
with larger scales.
Both of these types of couplers rely on tension to keep the couplers
engaged when passing over an uncoupling ramp or magnet. Or bumps and
undulations in the track, for that matter.
The "tension lock" coupler is the OO train-set type familiar from
Triang, Hornby, and others, and the variations designed by modellers in
EM/P-4 to look less obtrusive. AFAIK, no N scale manufacturers supply
rolling stock equipped with these. Some modellers have devised N
versions of these "invisible" couplers. I'm sure someone will direct you
to any relevant websites.
Over here, most new N scale product is now equipped with Micro-Trains
couplers. Micro-Trains makes mounting devices etc to convert all major
N. American brands, and also offers couplers that fit the NEM coupler box.
BTW, if you mix 4-wheel stock with body-mounted couplers and bogie-stock
with bogie-mounted couplers, you will have coupling problems. Body mount
all couplers, using long shanks on the bogie stock, or devices that
increase the couplers' swing.
Also make sure that all couplers are exactly the same height above the
rail. NMRA standard height is 0.216" or 0.548mm, measured at the
horizontal centre line of the coupler face. Easiest way to ensure this
is a coupler-height gauge. You can make one yourself: shape a small
block of hardwood, and fasten a coupler to its top. Shave away the
bottom of the block until the coupler is at the correct height. (5.5mm
above the rails, and allow at most 0.25mm variation, easily seen by
eye.) Glue a couple of pieces of strip wood to the bottom of the gauge,
centered and 9mm apart. This hold it in place on the track.
The standard Farish coupling is "Arnold" type. The common alternatives in N
Microtrains - US designed (sometimes called Kadee, which is the name of a
larger scale version). Work well if setup properly. Can be operated by
magnets buried in the track. Require two poles of the magnet to be presented
either side of the centre line of the track (so one arm goes left whilst the
other goes right). Can be done with buried fixed magnets, or fixed magnets
on mechanical linkage to raise/lower. Allows "delayed uncoupling" where a
wagon is uncoupled, then propelled down a siding in the uncoupled state.
And then the small cottage industry supplied types:
MBM - obselete "upside down tension lock". Still sold by the N gauge
society, I think mostly to those who adopted it years ago. Magnetic
operation. No delayed operation.
DG - available commercially (I think through MSE ??). Mixture of etched
parts and some fine wire loops. Magnetically operated (either simple
electromagnet coil, or movable fixed magnet), and allows "delayed
uncoupling". A bit fiddly to assemble.
BB - similar to DG. Arguably easier to assemble. Mechanically compatible
Sprat and Winkle. I don't know anyone using it in N/2mm, but someone must.
And finally the "roll your own":
Alex Jackson (or AJ). See Manchester MRS site for gory details. Can work in
N/2mm, but fiendishly difficult to make work reliably. Sprung variant
devised by Jim Watt might be better, but even harder to make. Works much
better in 4mm scales or bigger.
Electra. Rotary action DIY coupler. Somewhat similar in concept to the AJ,
but a lot easier to build in 2mm. DIY from bits of wire and thin tube.
Must be a few more somewhere...
Webmaster at http://www.2mm.org.uk/
Just to stir the mud a bit:
"Kadee" stands for KD, initials of the two brothers who founded the
company. Eventually, they split, and one of them took the N-scale
coupler. This descendant of the original Kadee now produces a large
range of N scale cars. They expanded in Z scale a few years ago, and
last year began production of HOn3 (HO scale, 3ft narrow gauge) cars.
Here in the US there's another. Sergent. Works magnetically, but with a
wand, not a magnet in the track. Take a look at:
But AFAIK they're only available for HO and may not look anything like UK
And I forgot one !
The MFK; absolutely brilliant idea, but the loops are too long for UK
stock, so the buffers end up too far apart.
and in video:
Webmaster at http://www.2mm.org.uk/
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