K11-*      SCREW-LINK / COMBO COUPLING 3D PRINTS £15.99/£12.50/£7.50/£4.99

We have designed and 3D printed working screw-link and combo knuckle-hook couplings for G-scale 1:29th or Gauge-1 10mm, 7mm O-gauge and 4mm OO scale. Each is printed in our black resin, with versions that are fixed, and versions that can articulate just like the real thing to be poseable however required.

On our Instagram account you can view a short video showing the operation of a combo coupling:

A screw-link coupling is the type fitted to most modern UK engine classes. For an example of a real screw-link coupling see:

Our models are sold individually and are available for the larger scales. The mounting has a partly drilled screw hole in the back for possible attachment to your model without glue. The hook and screw-link poseable jointed assembly slides in to the top of the mounting. Here are three of our K11-A couplings posed to show typical real arrangements:

Screw-Link Couplings G-Scale.

K11-AScrew-Link Coupling G-Scale-1:29th/Gauge-1-10mm£7.50
K11-BScrew-Link Coupling 7mm O-Gauge£4.99

The combo knuckle-hook coupling operated in either of two positions. Most often it is seen fixed in the hook position with the knuckle retracted and clamped against the front valance - a handle engages with a slotted plate. The knuckle jaw can be released with the metal arm extending to a handle at the corner of the body, connecting by a cable to an eyelet on the top of the knuckle.

For G-Scale 1:29th Aristocraft Class 66 models are made with a much simplified combo knuckle-hook coupling fitted at one end of the model only. All of Bachmann's 4mm OO Class 66 models also have a one end only fitting, with a plain hook at the other end. Hornby's ex-Lima class 66 and 67 models have only vague hooks. All just wrong! The combo type of coupling was fitted to all Class 67, and with the exception of 66001 to all class 66 EWS, Euro Cargo Rail and DB Schenker livery engines - the same at both ends. Other liveries of Class 66 engine and 66001 have a screw-link type at each end.

We have created 3D printed fixed versions for each of the two usual operating options, as well as well as a fully articulated version that can be posed around three pivoting points for the utmost realism in the larger scales. For 4mm OO scale use we supply the model couplings as a pair with both of the fixed positions - for the larger scales the coupling versions are sold individually. In pristine condition, they are easy to fit with just a bit of glue around the back of the mounting.

Aristocraft G-Scale Class 66 Coupling.

Aristocraft's supplied simplification above
just doesn't have the right shape.

Real combo knuckle-hook couplings right -
photos by driver Brian Daniels.

Shown below our G-scale K11-C jointed
coupling, here painted and weathered, it
moves and looks like the real thing.
Real Comobo Class 66 Couplings.
Our K11-C Comobo Couplings.

K11-CArticulated Combo Knuckle-Hook Coupling
K11-DFixed-Hook Combo Knuckle-Hook Coupling
K11-EFixed-Knuckle Combo Knuckle-Hook Coupling

K11-FArticulated Combo Knuckle-Hook Coupling
7mm O-Gauge
K11-GFixed-Hook Combo Knuckle-Hook Coupling
7mm O-Gauge
K11-HFixed-Knuckle Combo Knuckle-Hook Coupling
7mm O-Gauge

K11-IPair Of Fixed Combo Knuckle-Hook Couplings
One Fixed-Hook & One Fixed Knuckle
4mm OO-Gauge

In the picture below, on the left Bachmann's coupling, right our K11-I 4mm OO scale coupling.
As well as being the right shape, our coupling fits correctly so the buffer can still move!

Top left Bachmann supplied coupling.  Top right our 4mm OO scale coupling.

For 4mm OO scale, Hornby have some very nice metal screw-link couplings that are available as spare parts. Tenmille produce an all metal kit AG257 which is of a different older design and has a much larger hook, said to be for Gauge-1 it's more like 16mm scale and it requires a lot of assembly with bending and screw thread tapping - that is however a heavy load bearing design, although not correct for a modern engine model.

Our 3D printed couplings are quite strong, but it's probably not a good idea to try to use one of the articulating versions as a functional coupling between models, as the pivots will likely snap under load. The O-gauge 7mm screw-link version should definitely be treated only as a cosmetic feature. We are able to print these in other larger scales if required - just ask.