Garden Railway Forum

Greetings to one and all - especially users of chopper couplings!

I have a simple question - which are the best chopper couplings available and why? OK, I know that's not a simple question and I also know that everyone will have their own opinion. Whatever your views I'd be delighted to hear them.

I'm still (well, only just if I'm honest) beginning the 'terra-forming' required to allow construction of my railway. As such considering rolling stock may seem a little previous, but with the imminent and very sad demise of Brandbright I thought I ought to consider buying a supply of any products they manufacture which may be needed in the future!

All the best,

Andrew

I have just ordered a pair of Roundhouse style scale couplings from Swift Sixteen to put on one of my engines. They looks nice, but I have yet to try their practicality. I guess their mostly for show.

Accucraft standard chopper couplings work well, but are a bit out of scale.

The Accucraft offerings I use work well, can be modified to taste (size) and are cheap compared to brass alternatives.

My own personal view of chopper couplings albeit the Accucraft type fitted to their otherwise excellent range of rolling stock, is that they uncouple of their own accord. Whether this is due to my track, vibration or whatever, they sometimes work fine and then suddenly unaccountably uncouple even on straight stretches of track.
As a consequence I now rely on 3 link couplings and they are cheaper!

I use Accucraft on all my UK outline NG stock and locos. Cheap and plentiful. Work fine but if you have uneven track, that may cause jolts, or poorly matched coupling heights you may experience the random un-coupling events described above. A safety chain is a good "fail safe" but you will still probably need the couplings to provide adequate control if propelling stock. And they look nice.

Take a a look at Festiniog/WHR 1:1 stock sometime, they have counter weights on their choppers to avoid random uncoupling events caused by sudden jolts. Max.

Accucraft for me. Recently they have come in an annoying gloss finish so they need a blast of matt black sporay before use. Not really a problem as I find the choppers too stiff so I normally take them apart and file a bit off to make them freer.

Thanks for the comments so far guys, they are very interesting. The importance of well laid track and carefully constructed stock to common standards are clear. Any aspect of engineering requires this to one degree or another and this goes as much for 12" to the foot scale as for any other scale. The difference is, I guess, that tolerances become finer as the scale reduces.

I'm interested to see little reference to Swift Sixteen products, which include the provision of bob weights and a 'hook' on the bottom of the chopper. These features ought to go at least some way to mitigating any short comings in either of the problem areas.

Keep the info coming, it's all good stuff!

Andrew

maxi-model:108885 wrote:Take a a look at Festiniog/WHR 1:1 stock sometime, they have counter weights on their choppers to avoid random uncoupling events caused by sudden jolts.

Ah, Festiniog chopper couplings are a thing of genius. They are nothing like the commonly available model chopper couplings, and I have never seen them modelled to replicate how the full-size ones work.

The chopper hooks are loose around the pivot but are fitted on an eccentric such that the bob weight hanging down tightens their hold on the adjacent coupler. To uncouple them at least one and usually both bob weights need to be lifted. This rotates the pivot so the hook moves around the eccentric to a position where it has moved outwards towards the end of the vehicle, so eliminating the tension on the hooks and allowing them to be lifted.

Swift Sixteen couplers look very nice and seem to overcome some of the Accucraft's noted limitations. But........er....not cheap at £10 each when you can get Accucrafts at £4.50....a pair. That's less than a 1/4 of the price. And you have to assemble an paint them too. A lot of cost difference with a loco a a small consist to kit up. But then again, quality is never cheap and probably does not amount to much when compared to the all up cost of a live steamer and a rake of some nice kit built Brandbright coaches. And now I come to mention them............Max

A tip I was given for Accucraft chopper couplings is to remove one blade per wagon/van/etc. and couple that end up to a blade on the opposite coupling which makes them work better over uneven or tight curved track.

Of course that only works best on a continuous layout - with an end to end layout & the loco running round required you can end up with 2 chopper blades again.

Chris Cairns

Thanks for the further info chaps.

Chris makes an interesting suggestion. Was this ever done on the real thing? I have a sneaking suspicion the Leek & Manifold might have.

Hi all.
Anybody using tenmille ag046 choppers. I am considering converting my 4/5 whr bogie stock and loco from centre buffers to choppers and these look ideal. Had a good look at the brilliant Swift Sixteen products at the Lincoln show but 12 couplings at £10:00 each comes expensive.
David.

Soar Valley Light:108953 wrote: Was this ever done on the real thing?

The VR used chopper couplings with only one hook on the 2'6" lines when first built. The hooks and coupling pins were easily removed and swapped to the other end if needed. No idea if they were any more reliable with one hook, but the VR used a latch that dropped over the hook and didn't fit safety chains. The choppers were too weak for the longer trains the garratts could haul and they were replaced with small MCB knuckle couplers in the '20s, still used today on Puffing Billy.

I know one modeller that tried using Accucraft couplers with one hook removed and found they were even more prone to uncoupling, so he went back to two hooks.

I use Accucraft W&L type choppers and have had no problems in service. The track where I mostly run has very good trackwork though and I'm careful about maintaining a standard coupler height.

Playing around with Accucraft choppers on the bench, I've found that if the slack runs out violently, the hooks can jump high enough to uncouple, but the design tends to prevent that if tension is kept on the couplers.

Trackwork, coupler height and driving style could all affect operation, as on the prototype.

Some railways had a weight on a chain that was thrown over the hooks to keep them in place. No idea if that could be made to work in small scale. The latch arrangement used by the VR and other railways may work, but I've had no reason to try it.

Regards,
Graeme

Soar Valley Light:108953 wrote:Thanks for the further info chaps.

Chris makes an interesting suggestion. Was this ever done on the real thing? I have a sneaking suspicion the Leek & Manifold might have.

Hi,
The L&M like several others have a screw mechanism to tighten the buffer faces together. This means they never rely on gravity to stay coupled. It also means less jarring between vehicles and a smoother journey in the coaches. They are all single ended too so the chopper is only on one end - not a problem on lines with no turntable.

Thanks Engineer, that's very interesting, I had no idea it was such a sophisticated arrangement. It makes perfect sense when you explain it. Thanks for your post.

Andrew

Can't say I've had any real problems with choppers coming uncoupled. I've got a good mix of accucraft and Tenmile. I've also fitted the swiftsixteen choppers to a couple of my locos. Expensive but they don't look as oversized as the Accucraft ones do. They do need abit of work on the chopper themselves as I find they don't sit into the accucraft choppers as designed.

For looks, I'd say Brandbright or swiftsixteen, cheapness I'd say accucraft. I have got some chuffed 2 bits, I think but I can't find them on there website, white metal ones that with a little work will couple to other makes. The only down side is they are white metal so Ive only used them on lightweight stock.

I have never had a problem with Accucraft couplers uncoupling while on the move and that is despite me modifying the ones I use so I would say if you have these issues it is down to uneven track or incorrect coupling heights between rolling stock/locos.

Hi all.
Bought some brass chopper couplings from Slaters yesterday. Had a good session today putting them together but had to put some of my own ideas into fitting them to my coaches as the small instruction sheet does not make things very clear. One great addition is one coupling has an up and over hook that locates over a horn on the opposite chopper, holding it in place. Hopefully the photo makes this clear.
Also, when not being used the couplings retract into the coach somewhat using hidden springs. When connected and pulling, the couplings pull out by about 7/8 mm allowing for a greater sideways movement on curves.
Anybody have any ideas on how to simply blacken the brass as I want it to look like old metal not painted.
David

carrs brass blackening solution, or gun blue?

Si & Rob`s Blue Jollop works well on brass:

http://www.modelearth.net/

Can we have more pictures of the chopper coupling please? I would like to see it connected if possible. How much a set?