society kit and greenwich coupling

[5113GBAK]

Hi all
I've just purchased four of the Soc RNAD vans which come without buffers, couplings and safety side chains.  I have tried to seek out pictures of the real thing without success.  I would like to use Grenage couplings but don't know if straight or cranked is the way to go.  Also  the chain needed for the side couplings, could you name a supplier and what about buffers?
Graham

[Graeme Dunbar]

Hi all
I've just purchased four of the Soc RNAD vans which come without buffers, couplings and safety side chains.  I have tried to seek out pictures of the real thing without success.  I would like to use Grenage couplings but don't know if straight or cranked is the way to go.  Also  the chain needed for the side couplings, could you name a supplier and what about buffers?
Graham

There are a selection of photos on the L&B web site.

https://www.lynton-rail.co.uk/news/view/ex-rnad-box-van-arrives-at-woody-bay



The Greenwich coupling serves as a central buffer.

Possibly the best source of fine chain is a model boat supplier such as Cornwall Model Boats.

https://www.cornwallmodelboats.co.uk/cgi-bin/ss000001.pl?page=search&SS=chain&PR=-1&TB=O&ACTION=&ACTION=Go%21

[JulienW]

Hi all
I've just purchased four of the Soc RNAD vans which come without buffers, couplings and safety side chains.  I have tried to seek out pictures of the real thing without success.  I would like to use Grenage couplings but don't know if straight or cranked is the way to go.  Also  the chain needed for the side couplings, could you name a supplier and what about buffers?
Graham

First off rather than 'straight' or 'cranked' as far as I am aware the Greenwich couplings come in 3 'flavours' - the standard one (CPL 1), the 'wide loop' one (CPL 1w) if you have very tight curves / long overhang on the stock, and the one to fit in an NEM pocket (CPL 3).

All of the couplings come as a flat brass etch and will need assembly (but no soldering is needed), and will act as both coupling and central buffer much like the 'chopper' couplings on the real thing. Therefore there is no need of a separate buffer (unlike with standard gauge stock).

You could add the safety chains, but in 1:76 scale these really are tiny - probably smaller than the chains used to represent standard gauge 3 link couplings - and with Greenwich couplings there's no need to add them other than as non-working cosmetic items.  In that case I'd suggest using some loosely twisted (very) fine wire - something soft like 5 amp fuse wire if you can get it - to get the look of the hanging chains.

So, as you should only need to buy couplings I'll move on to those.

Personally for these kits I wouldn't bother with the NEM type (CPL 3) as to use them would mean having to buy pockets to stick on to the vans which seems an unnecessary expense (I use them to convert ready to run stock that already have the pockets though).

The CPL 1/ CPL 1w once made have a 'straight' shank (the end opposite the buffer), and once you have fixed them in place the idea is to bend the brass shank up or down to get the coupling to the correct height. The recommendation for 009 is a mounting height 5.5 mm above the rail head.

That's going to need you be able to measure the height, but some form of jig to set this makes life a lot easier.

There's a Greenwich etched gauge (GAG 1) that sets the coupling height for 009 (and OOn3) as well as a depth gauge for setting the operating magnets. It's good, but being a flat etch needs to be set vertically to accurately set the coupling height and I find it a bit awkward to use. As an alternative (and one I recommend) there is the RT Models gauge (NGWC010) with is a cast resin block that sits on top of the rail with a strip on the base to locate it between the rails. One end face has a straight edge to mark the height on the wagon buffer beam and the other peg on it for checking the action of the coupling once fitted. Finally there is a DIY version made by fixing a short length of track to a piece of wood then fixing a screw into the wood between the rails at one end.  By using a screw with a flat top (like a 'countersunk head' screw) and only screwing it in until the top of the head is 5.5 mm above the top of the rail a very effective jig results.

For reliability in use ultimately the actual height is less important than having the couplings of ALL of your stock AT THE SAME HEIGHT.  The advantage of using either the Greenwich or RT Models gauge is that most other 009 modellers are using the same gauge, so if your stock goes visiting other layouts the couplings will work, and likewise stock visiting your layout will also couple up to yours.

As to suppliers of Greenwich couplings there's Dundas Models who seem to have everything in stock, and Light Railway Stores (who currently show then as out of stock)

It might also be worth looking at the links on the Greenwich Couplings website.

Hope that helps...

[5113GBAK]

Julian
Thank you for your input, lastly how are the couplings fastened to the bottom of the van?
Graham

[JulienW]

I realise that was something I missed Graham, (sorry) so I'll précis the way I do it.

The first step is to work out where on the wagon the coupling needs to be mounted as often the buffer beam needs to be cut away for the shank (where the straight edge on the RT block gauge comes in very useful) and some packing needed on the underside of the floor. For packing I use offcuts of plastic card sheets to bring the level to the same as that of the cut out stuck on with a solvent adhesive (the same stuff as I use for building the plastic kits).

It is also possible to bend the shank to raise or lower the coupling, even to the extent of bending it around the buffer beam, but the metal is not that thin so does not bend easily, and you'll only really get one chance to get it right as it's difficult to bend the metal back to try again without it breaking (due to stress fracture).

The shank on the CPL 1 has a number of small holes (I think it's 3 but I can't recall exactly) etched through. This means that once I've stuck them in place - cyanoacrylate (super glue) will be fine but make sure you have the coupling parallel to the rails - I can drill through 2 of the holes into the floor and insert a short bit of wire, bend it over and add another bit of super glue to hold it in place, or make a 'staple' that fits through both drilled holes.

Perhaps something about how far away from the end of the wagon the buffer needs to be added here. There's no hard and fast rule, but it needs to be far enough out for the loop to rise up as far as possible as a minimum, but not so far out that there isn't enough shank to stick to the floor (a disadvantage of bending the shank is that it effectively makes it shorter which can make fixing harder).

Superglue is not very strong in a 'shear' direction (along the line of the joint) which is what the coupling will be subjected to in use. The wire pins reinforce the joint to counter this, using 2 prevents the coupling 'pivoting' should the main joint give way, and by bending them over it stops the coupling dropping off.

A final tip to add about making the couplings in the first place is to make sure that the pivot for the loop is free running. The first step is to run a small cutting broach through the pivot holes to remove any sharp edges left from the etching process, but you could also do this with a fine drill bit held in a pin vice (not in a dremel!) with the drill a smidgen larger than the wire you'll be making the pivot pin from. You may also need to adjust the way the 'ears' that make the pivots have been bent down (often those on the coupling body need a little squash to fit nicely within those on the loop).

The aim is to have it so that when you rotate the coupling from horizontal to vertical (buffer pointing upwards) the loop flops over backwards, and also drops back onto the body of the coupling when you return it to the horizontal. Once you have that you can bend over the ends of the wire pin to fix it in place and move on to fitting the coupling to the wagon.

[Hugh Norwood]

Tramfabriek make some couplings with extra long shanks (that are compatible with Greenwich by the look of them)

Here https://tramfabriek.nl/couplings.html