Auto couplings: A ‘Dingham Derivative’

I decided to use Dingham couplings years ago primarily to speed up the coupling and remote uncoupling process, thereby attempting to avoid use of the ’hand of God’ that to me, is totally unprototypical. As I get older it is paying dividends since I can couple up 20+ goods wagons in seconds rather than taking half an hour with 3-links. Eyesight and hand-eye co-ordination will no doubt deteriorate with age.

What follows, are some modifications I have made to the standard Dingham autocouplings to enhance their flexibility and increase their robustness. Having experienced cases where the standard Dingham couplings are bent from heavy shunting, movement in transit boxes etc., I now double the thicknesses of all hooks, latches and loops by using two of each fret (as prepared in Photo 1). Photo 1. The components of a single coupling before laminating.

1. Two hook frets are soldered together to form the coupling hook.
2. An additional 1.0 mm hole is drilled below the hole for the latch in the hook to accommodate a 3-link coupling (Photo 2). Photo 2. An extra hole is drilled in the hook to accommodate the three link chain.

3. The tails from the two latches
4. The slot at the back of the latch where it is soldered to the hook, is opened out with a 0.9mm needle file to enable the latch to fit over the two thicknesses of hook fret. If the slot is found to be tight, then the area where the latch is to be attached to the hook should be gently filed down to enable complete free movement. The rear of the latch corners should also be rounded-off to avoid contact with the 3-link coupling (Photo 3). Photo 3. The laminated parts before assembly

5. The 3-link coupling etc enables the wagon, loco etc. to be coupled to non-Dingham fitted stock, and to hang down prototypically when the wagon rake is viewed from the side (Photo 4 below).

6. If a cast loco coupling with tommy-bar is required, then a slot, opened out from two 1.0 mm holes, is made to accommodate the larger coupling and slew it to the side of the buffer beam (as per GWR practice).

1. Again, two hook frets are soldered together as per the latch system.
2. One of the loop frets has the dropper arm removed along with the two fold-up side location brackets. – this loop is soldered below the unmodified loop to enable the side location holes to be folded upwards for attachment to the hook.
3. Once the two loops are soldered one on top of the other, again the rear slot is opened out to 0.9mm. The remaining dropper arm is folded up and the steel dropper made up conventionally, as in Photo No.3.

Both couplings should be washed and stained with Birchwood Casey gun blue, I have found Carr’s products will quickly flake off. Some additional painting may be required over any solder. As an aside, I recently noticed that Lee Marsh has introduced some very similar couplings for his carriages. The usual disclaimer applies – I am simply a very satisfied Dingham customer. Photo 4. The improved appearance gained by fitting three links is apparent in this view.