Coupling question

[Thunderforge]

Having always used N-gauge knuckle-dusters or OO scale tension-lock couplings I’ve never really thought about it, but now I have some O-scale three link couplings...

 

Do you join the chain from the front vehicle to the back vehicle, or the back vehicle to the front vehicle? Or do you use the least rusty? Or the instanter over the three link and the screw over the instanter? Or what?

 

I figure there will be a standard practice, (and I’ll bet the GWR had a different standard practice to anyone else!)

[brossard]

There may have been a standard practice and I know that using the loco coupler was preferred.  As for the other wagons I don't know.  I find it refreshing to be able to use prototypical couplings in O gauge.  You are probably right about GWR.

 

John

[Siberian Snooper]

The only hard and fast rule is that you use the coupling on loco to the first vehicle, as this one should be the best maintained, other than that you pays your money and takes your pick. I always prefer to use the coupling on the vehicle to my right.

 

 

[Thunderforge]

It’s funny, my first thought was not to use the locomotive coupling because a truck out of commission with a faulty coupling is less annoying than a locomotive out of commission with a faulty coupling. BUT the point of most stress on any train is that first coupling, so presumably a loco rear coupling is far more reinforced than a wagon/carriage coupling? (which could end up in any position in a train)

[The Johnster]

Normal prototype practice was to use the loco screw coupling to couple to the train, except in the case of class 9 unfitted trains with instanter couplings in the ‘long’ position, to run at a max 25mph, when the leading wagon’s instanter was used in the ‘long’ position. 

[Steamport Southport]

You would usually use the loco coupling. Or which ever is best for the job, screw, then instanter, then three link. If the loco only has a three link and the wagon has a screw then you would use the screw coupling.

 

But if you have two similar couplings between vehicles you would use the one that is most convenient to the shunter coupling them and whichever side he is on. Swinging them one way is much easier than the other for most people. Usually from right to left. Many shunters in busy yards used poles to couple rather than going between vehicles.

 

 

 

Jason

[BR60103]

I asked at our club and received a sheet of BR specs. IIRC you used the fanciest coupling.

An ex-driver said that they used the lightest one.

 

[brossard]

Worth noting that 3 link couplings would be used for unfitted wagons.  Many kits only supply 3 link despite the fact that there were often variations that were vacuum fitted.  Goods stock that was vacuum fitted would usually be fitted with instanter couplings but sometimes you would find screw link.  Passenger rated stock would always have screw link couplings.  Dapol do some very good value packs of screw link couplings.  You can get more elaborate screw link coupling kits that even work.  Took me 3 hours to assemble the screw link coupling on my latest van.

 

John

[34theletterbetweenB&D]

10 hours ago, Thunderforge said:

It’s funny, my first thought was not to use the locomotive coupling because a truck out of commission with a faulty coupling is less annoying than a locomotive out of commission with a faulty coupling...

I have heard it said by a railwayman of some standing in operational matters, that the reason for having the standard practise of using the loco coupling to couple onto the train was for precisely this reason. The 'why' being that very often the loco couplings are hung up on the drawhook and the temptation is to couple the train on by placing the vehicle link on top. That then puts all the trainload on the tip of the drawhook, and repeated use will lead to failure.

 

4 hours ago, brossard said:

...Goods stock that was vacuum fitted would usually be fitted with instanter couplings but sometimes you would find screw link...

Other way around I would suggest. Screw link was standard for vacuum fitted, instanter a relative rarity, and mostly on unfitted stock during the steam operations period. Does any scholarly study exist of the deployment of screw link vs instanter on both fitted and unfitted stock? I have never seen such.

[Fat Controller]

From observation, I'd say that Instanters were to be found on vehicles vac-fitted in the 1950s from unfitted stock, many new-build BR fitted wagons and also on most ex-GWR fitted stock (the coupling was patented by the GWR, who would demand a licence fee for using the design.) Three-link couplings were used mainly on smaller minerals, both XPO and 16-tonners. A note from 'An Illustrated History of BR Wagons' says 'It was policy to recover all screw and Instanter couplings from condemned wagons, to use them to replace 3-link couplings, until all stock was provided with them'. The photos in the afore-mentioned volume seem to show the only 3-link couplings to be on ex-works , unfitted, new-build stock in the 1950s, unfitted pre-Nationalisation stock and ex-BR wagons transferred to industrial service.

The advantages of the Instanter were that the shunter didn't need to go between the wagons to couple/uncouple, and its 'universality'. It was also considerably cheaper than a screw coupling, both in initial cost, and in subsequent maintenance.

I fear a scholarly study would prove difficult, as I doubt any central record of couplings actually fitted to wagons has ever existed. Far more significant differences escaped the records, such as which 16-tonners had been partially equipped in anticipation of vacuum- fitting, but never received cylinder and 'bags'.

[Il Grifone]

Instanter couplings were a GWR invention (like most of the good ideas ) (1908 IIRC) and used on vacuum fitted goods stock. I think the LMS adopted them around WWII (I am open to correction on that one) and they came into general use after nationalisation. The BR design was different from the GWR design however. Most BR built fitted goods stock was so equipped.

 

The advantages were cost and ease of use (a flick with the shunter's pole rather than going underneath and screwing the d**n thing up!).

Generally they used 1'6" buffers as well.

Edited September 30, 2019 by Il Grifone

[34theletterbetweenB&D]

I have looked at this in the past on the basis of inspecting photos of new build BR stock. My conclusion then was that instanters were as likely to be found on unfitted as fitted, and that screwlink outnumbered instanter  2:1 on BR's fitted wagon build. Now that's in no way a reliable sampling, relying on a selection of those photos that clearly show the coupling and brake pipe: but in lieu of better evidence I'll go with screwlink much more numerous than instanter on fitted wagons in the BR steam period, what with most of the pre-nationalisation fitted wagon build having screwlink.

[brossard]

I'm coming at this from the point of view of modellers getting the couplings right on their wagons.  For most 00/4mm modellers the coupling question is academic I think (although there are those who use prototypical couplings).  So, for me, the rule of thumb (but not an absolute rule) is instanter couplings for fitted goods stock.  Also, for the modeller as for BR, instanter are cheaper and less of a faff than screwlink.

 

John

Edited September 30, 2019 by brossard

[The Johnster]

Certainly by the 1970s, there were no 3 link couplings on revenue earning stock though some departmentals retained them.  Instanters were used on all types of freight stock including vacuum fitted and XP rated vehicles, but screws appeared on all sorts of fitted stock, including minerals, as well.  I believe (but cannot state authoritatively) that 3 links disappeared on revenue stock with the last wooden XPO minerals.

 

As well as the Class 9 rule, the screw coupling of the leading vehicle was used to couple the loco on the Port Talbot-Llanwern iron ore tipplers, the heaviest trains on the network in those days.  The wagons were fitted with special revolving heavy duty knuckle (buckeye) couplers at one end so that they could be tipped at Llanwern without uncoupling from the train, and the end vehicles of the sets were fitted with special heavy duty screw couplings that were stronger than loco couplings to take the very heavy loadings.  This is an exception and not normal practice on other trains, but the ARC and Yeoman tipplers had a similar system I believe.

 

The Ideal Wagons Committee, set up by BR shortly after nationalisation to sort out the mess of poorly maintained and obsolete wagonry which they'd inherited from the Big 4 after years of underinvestment and a war, oversaw a cull of older general merchandise wagons on 9' wheelbases that was effectively complete by the late 50s and of 7-plank XPOs by the mid 60s (though many of these survived in NCB internal use).  The later stages of this operation were much assisted by the general decrease in traffic.  10' wheelbase general merchandise Big 4 stock in good condition was refurbished with vacuum brakes and instanter or screw couplings, any unfitted being given instanters.  The instanter was a clever idea which could shorten the distance between wagons for fast running and lengthen it for ease of shunting in local trip working; it had 'horns' on the centre link to assist lengthening or shortening with a shunting pole without the shunter having to go in between vehicles.

 

From a modelling perspective, if you are using scale couplings then you should if you can model the type of coupling that was fitted to the prototype.  For the BR era this means screw couplings on locos except for some 3 link on steam locos not fitted with vacuum brake (04, Q6, J27 for instance), instanters on general mechandise but you can get away with 3 link on older wagon pre about 1958, 3 link on XPO wooden minerals but instanters on steel bodied minerals.  Some fitted freight stock has screws, as do all passenger and NPCCS including milk tanks.

 

For earlier periods, pretty much all freight stock has 3 link except XP rated which has screws, except for the GW which used their instanter design, which was not as heavy duty as the BR variant.  Passenger and NPCCS had screws from about the 1860s onwards, but older stock was in service for some time after this, on which 3 link with side chains were used.