HO Coupler Size Question

I haven't followed this thread completely and so have missed some comments about couplers other than North American style knuckles.

Greg Procter,

you model European, so what type of coupling do you use? Chain & hook with buffers? If not, then what? Please explain in detail and do not assume that I know about the workings of model couplers other than Kadee, Mantuas, Sergeant, MDC, Monarch, and Baker, because I do not. Those are the only ones I have ever worked with other than toy train couplings, i.e. American Flyer, LGB, and Lionel. I seem to recall you saying that you used magnets however, which would imply the use of Kadees. If that is the case, how do you square that with European prototype modeling? Not an indictment, merely an interested question. If it is a device of necessity, that is perfectly understandable. I say all this because I have become quite infatuated with contemporary British equipment, much of which appears to still use buffer and chain. Has there ever been, and is there now, a sucessful application of this method of coupling to 3.5mm or

4mm scale model railroading? I mean in such a way that shunting can be done with some degree of authenticity.

I have two different areas of modelling, South German 1922-32 (Wurttemberg) which is most of my modelling including my layouts, and British HO rolling stock, for which I set a different lower standard and which gets occassional running rights in S.Germany.

The German prototype uses buffers, hooks and screw links - this locks trains as a single unit. For the models, most have the extending coupler mechanisim which limits one to a coupler which forms a rigid bar.(otherwise with heavy trains the coupler mechanisims extend which eventually derails the rolling stock) I use my own redesign of the Maerklin coupler with an etched loop and magnetic uncoupling dropper mounted on the Ma plastic base.

The British rolling stock had three different couplers:

- Buckeye on passenger stock from the early BR days 1950s on.

- Buffers, hooks and screw links on older passenger stock.

- Buffers, hooks and loose "3 link" chain couplers on goods stock. Typical British goods trains until the 1960s were short wheelbase 4 wheelers hauled by 0-6-0s which ran at about 15 mph. Braking was by a combination of the loco and a light 15-20 ton brake van at the rear. A typical British goods wagon measures about 3" long in HO. The coupling I have finally settled on consists of an N gauge head on a length of steel wire fixed at the center of the wagon. An imitation 3 link chain with an iron end link hangs from the wire, in line with the bufferbeam hook. Running this over a magnet pulls one coupler head down and uncouples the wagon. A wire stirrup behind the buffer beam limits the downward travel and the buffer beam sets the upper position. This coupler mates simply with NEM couplers by ridding up over the hook, but only uncouples by hand.

The original NEM coupler was a pivoted center buffer with a hook top center. A separate loop is hinged on the buffer close to the buffer beam and has a rigid dropper ahead of the pivot which connects with a mechanically raised ramp between the rails. Because of the side buffers (non-functional) the couplers have to keep the wagons well apart so that curves can be negotiated without contact between vehicles. The current vehicles mostly have a mechanisim so than angular displacement between vehicles results in the coupler being extended from the vehicle. This requires the couplers to lock into a rigid bar. The newer NEM couplers now have a flat buffing surface, the hook and a loop which allows almost no slack.

Kadees don't work successfully with the extending mechanisims because they don't provide a rigid bar connection. With short trains this isn't a problem, but with heavy trains and flexible coupling the extending mechanisims become extended and apply side forces to the rolling stock. That's still not a great problem with those huge NEM flanges, but of course I use NMRA wheel standards.

We have to make compromises - I've chosen operation over appearance.

I think the loose chains disappeared in the 1960s, being replaced with screw link couplers (and more modern wagons)

Many UK modellers ( they divide themselves into proprietry modellers OO scale on HO track, or Scale 4 on 18.83mm etc track) use the hook and chain coupling on small modular layouts. Hook and chain coupling means they use the wagon buffers for pushing, which limits track radii to a minimum of 36-24".

Regards, Greg.P.

Hi.

Much has been posted about more realistic appearance of track, wheels and "scale" coupler knuckles including their operation, but nothing has been said about their effects on the more noticeable close coupling. This is seen everywhere and not just closeup. With the exception of Accumate Pro, Kadee 711 and Sargent, none approach prototype head length to the pulling face. Due to excessive slack in knuckles and draft gear, close coupling is difficult to achieve.

Measuring methods and results may be found on my site, along with history, evaluation, mounting solutions and examples with images. Close coupling is covered in depth. The interaction among rolling stock lengths, curves and couplers is also presented.

For more details with methods and extensive discussion of problems and solutions, see first site below in couplers and curves.

Hope this helps.

Thank you,

Budb

Author of:

MODELRAILROAD TECHNICAL INFORMATION

PROTOTYPE TECHNICAL INFO FOR MODELRAILROADERS (Revised. New address) Moderator of: MR TECHNICAL HELP GROUP HELP GROUP

I see, I think I might be interested in doing a very small bit of Scale 4 then. I like the idea of actually having working buffers on the wagons. I will have to investigate all this further.

Then visit , there should be enough to get you started.

Keith

Make friends in the hobby. Visit Garratt photos for the big steam lovers.

Be warned that the hook and link couplings are extremely fiddly in the smaller scales. People who do a lot of shunting/switching use one of the automatic couplers that still let you use working buffers.

I used prototype hook and link in OO. They're horrible under corridor connections (diaphragms).

The sheer fiddlyness is what made me start looking at O-scale, where I've been since the early 1980s.

The Alex Jackson couplers work in 4mm scale OO/S4/P4/EM/etc. I'm not sure if Dinghams are produced in 4mm.

Both these are unobrustive and provide advance uncoupling like Kadees.

The Dinghams use a carefully shaped hook, a single link and a latch. Alex Jacksons use a cunningly shaped wire hook at 45 degrees to the vertical.

Do you model Scale Four? Are the 66 class available in scale four or are they 4mm scale on 16.5mm gauge? Which is it? I already model North American 3.5mm scale on 16.5mm gauge. If I had to scratchbuild 18.83 mm gauge track and bogies, I might not be able to find time for it. I really do like the modern British outline stuff, but not enough to make it my principal hobby interest. I will go look at the web site later tonight. It is Five PM Friday here right now and I have to take the Mrs. out to dinner and then go to an operating session at a friend's.

small modular

limits track

The idea of working buffers and corridors is intriguing. In years past I was put-off by the toyishness of all the European outline models we got here in NA. especially Marklin, as well as some of the British outline stuff as well. The internet has been a good source of information on this area of the hobby that shows that there is fine scale interest and that there are good models available. I am continually awed by the Dyserth Road and would like to do something similar in a larger arena where the equipment could have more room to operate.

Yes, properly called Protofour.

Neither at this moment, the Lima one is off the Market and not recommended anyway. Bachmann have one promised, see

but not yet arrrived, when it does it will be 16.5 gauge but a wheelset exchange should be a 5 minute job. Bachmanns modern stock is generally good, from Hornby only the Class 50 so far but more will follow.

Track is available assembled, or more economically as moulded sleeper bases that just need the rails sliding in, turnouts you have to build but there are good kits. See

Keith

Make friends in the hobby. Visit Garratt photos for the big steam lovers.

Working buffers would be rather difficult to do as the tension coupling needs to be screwed together putting compression on the buffers in order to work well. IN addition, the compression of the buffers needs to be very gentle or the cars will tend to straighten themselves out in the curves which isn't a very good thing to have happen. Remember that our curves are a lot sharper than the prototype ones are! Also, the train length can't be too long or the buffers will just collapse on a push of the cars. Probably the same sort of problem that the prototype has with long trains.

-- Why isn't there an Ozone Hole at the NORTH Pole?

Not necessarily. Magnetic buffers that are in reality free-floating with only a stop to keep them from being pulled completely out would work nicely. They could have a very weak spring to retract them when uncoupled like the Kadees do to keep the knuckles closed. That way they would always look proper. The "chain" could actually be a stiff piece that only looks like a chain, but hooks onto a pin, or something similar, in the receiving wagon. When uncoupled it would look like a free-hanging chain. You might have to use a little coupling tool to couple and uncouple them. but I could live with that. I already operate my Kadees that way anyway.

I am well aware of that. A one degree curve in 3.5mm scale is 20 meters radius. Rather large for a home layout.

Well, I am quite sure that some ingenious modelers of European outline equipment have come up with a way to make prototypical, or very near prototypical, couplings work ~and~ look good. I have gobs of photos of 66 class loks pulling 35 car coal trains with chain & buffer couplings. If that is as long as they run them, then there is no reason for me to want to run them longer. I need to be careful not to try modeling British railways while thinking in North American scope. That won't work at all. Besides, I haven't gotten the first model yet. I've only just expressed an interest in it.

It looks like a good way to get a great deal of operation, with many trains running, in a conservative space. Built in North American walk-around style with radio control DCC, you could easily keep six to ten train drivers busy all evening. Not saying that I would ever actually do it, but it is fun to contemplate. And I ~do~ really like the look of the equipment. I would have to study the signal system and figure out how it works, as I do not know British signaling practice. I do have a friend and fellow modeler from Europe who is quite knowledgeable on German and Swiss signaling practice. Maybe he could help. He models the Gotthard Line from Zurich through Schwiz, Goschenen, and Bellinzona to Chiasso.

See my web page for some pictures showing why I think the KD78 is the best coupler to date.

My layout was built before the introduction of the scale couplers. I have had no observable decrease in coupler operation reliability. My track is far from level, however I use curves of 910mm radius or larger. I only use the KD's for operating couplers, and only install scale KD's No's 58 and 78 on new equipment. Clones are used only as dummies, glued shut.

In article snipped-for-privacy@4ax.com, Keith Norgrove at snipped-for-privacy@fiction.piplex.com wrote on 1/21/05 19:44:

I would be interested in one myself, with which I could have fun...a Class

66 in BNSF or CSX, anyone? :-)

I'd leave mine as a 4mm model on 16.5mm gauge track, which is a reasonable compromise. Equip it with Kadees, and use it to pull stack trains...

Dieter

The NMRA has failed in H0. Not one turnout manufacturer uses the NMRA standard. The NMRA standard is difficult to manufacture and produces coarser than necessary track and wheels. Also the KD is not a NMRA stand. Nothing to do with the NMRA standard coupling which is not supplied on RTR H0 models.

I won't be holding my breath.

The NMRA has failed in H0. Not one turnout manufacturer uses the NMRA standard. The NMRA standard is difficult to manufacture and produces coarser than necessary track.

There is no need for experimentation, there are numerous modellers who have already proved using finescale track and current RTR finescale wheels works better. Se my web page for the dimensions.

Are you saying they aren't 9.93mm high?

NMRA STANDARDS, S-2 Coupler Standards.

9.93 mm is the mounting height measured at the horizontal centre line of the coupler face.