Kadee Couplers

[cambo74]

Hi there - im sure there are lots of threads for this but simple question - which Kadee Couplers do most of you use for UK 4mm Scale Locos ?

 

Cheers

Ben

[BR60103]

If there are standard NEM pockets I use one of the 17-20 series, picking a length that lets it stick out past the buffers.

I also use one of them if there is a tension lock screwed on from below as that is the right height.

Often I can't if the coupling is moulded into, say, a bogie.

 

[34theletterbetweenB&D]

This will be dependent on the loco design, the positioning of the coupler pockets if available, the minimum radius on the layout, and the other vehicles on the layout. As above, 17-20 for coupler pockets conforming to NEM standard for height; combined with retraction of sprung buffers/modification of fixed buffers as required, to enable the shortest possible Kadee to be used; for the purpose of having vehicles coupled up at scale separation (30" minimum radius running lines).

 

With the majority of my stock comprised of the older Bachmann designs with the coupler pocket overheight, I also make extensive use of the no5 directly melted into the coupler pocket, comes out 'bob on' gauge height. Alternatively an NEM fitting type can be screwed on to the pocket underside, and there are possibilities in inverting the coupler pocket and not pushing it fully home in the locator to set at correct height. (And doubtless yet more such dodges.)

 

If the question is  'what should I have a stock of?' my suggestion would be keep at least one pack of each of 17 to 20 at all times, so that you can always test which is ideal for the stock, and systematically order more of whatever is required.

[cambo74]

Cheers guys

[ejstubbs]

Per 34C's answer: it depends.  On what locos you have, what stock they will be hauling/propelling, what radii you have on your layout etc etc.  Basically, there are too many variables for there to be a simple answer.  The rule of thumb is to have the inner face of the knuckle as close as possible to being inline with the faces of the buffers.  But even then the only way to be 100% sure is to test every item of stock in all likely combinations on the most challenging sections of your layout, such as small radius reverse curves (e.g. crossovers) and the tightest curves on plain running line.

 

Bottom line is: you will end up having a small stock of most sizes of your preferred Kadee coupler types.  If all your stock has NEM pockets (and they're all at the right height) then you can probably get away with just number #17 to #20.  If you are going to need to convert non-NEM-fitted stock then I'd go for a range of sizes and heights in the #14x series (the "whisker" couplers).

 

I'm not a fan of hard-mounting (e.g. screwing or gluing) NEM Kadees to non-NEM chassis: IMO it robs them of one of the pivot points that makes them work so well i.e. the flex in the NEM pocket fishtail.  That means that the correct operation of the coupler then depends solely on the pivot just behind the knuckle, which sometimes doesn't give great results on tight curves - you can often see one the knuckles being pulled open because there's not enough sideways play in the couplers.  #14x couplers mounted in a gear box have the pivot further back under the chassis, like a NEM coupling in a fishtailed pocket, which IMO allows the couplers to work the way they're designed to.  Of course some NEM pockets are rigidly mounted to the chassis anyway; I'd actually be tempted to lose the rigid pocket altogether and fit a #14x coupler instead.

[boxbrownie]

I decided (most likely) to standardise on Kadees for my new layout and stock, it’ll be all NEM socketed I would imagine so I ordered two packs of 18, 19 & 20 type, I tested the 18 on a couple of Dapol trucks today and they were bonk on the correct height and obviously a doddle to fit, now as to the uncoupling arrangement, I ordered a pack of neodymium bar magnets for a trial and fitted under the Trix-C track I am using work very well, BUT I found just running over them they uncoupled the trucks, so I decided to add some drag by putting a bit of soft foam between the one axle and the chassis to give enough drag to stop them uncoupling which worked, and still free enough to run without too much effort, I mention this as I don’t particularly want to do this with every piece of rolling stock and was wondering what other people do to avoid this issue?

Edited April 2, 2020 by boxbrownie

[nswgr1855]

 I have a small collection of UK 00 models, and have noticed most UK 00 have steel axles which are magnetic. This makes uncoupling using magnets unreliable and visually unrealistic with the wagons being pulled towards the uncoupling magnet. Using the NEM pockets also detracts from the appearance of the couplers. I use Kadee couplers on my H0 NSW trains, and use magnetic coupling with varying levels of success. To get the most reliable magnetic operation, I have found I needed to replace all wheel sets that have mild steel axles and any mild steel wagon weights. Use only one size of Kadee coupler head, either the old standard size or the smaller H0 scale head size. Use whisker couplers , remove excessive end play from locomotive and wagon axles, and of course adjust the heights to match the Kadee H0 height gauge. Do not use clones, only genuine Kadee's. Finally use the Kadee 810 electromagnet designed for O gauge, and mount them under my sleepers. Wire the coils in series and use 24Vdc. The other magnets can be cheaper, easier to install but you can get frequent unwanted uncoupling. I weight my wagons to the AMRA standard, and also use the AMRA minimum radius standard https://amra.asn.au/standards/ . I use 0.3mm wire on some brake vans  axles as a brake to stop them rolling away on some sidings which have a grade on then, as per the prototype location I have modeled. Do the above and you can achieve 99% plus reliability. Using DCC with keep alive capicators in locomotives also improves reliable operation.

 

Terry Flynn.

[boxbrownie]

I find the drag induced by the foam is enough to stop magnetic attraction issues with the axles and makes coupling/uncoupling reliable rather than adding weight as advised by Kadee.

[Butler Henderson]

I fit loose wagons with the original Bachmann wheels that had stub axles on a plastic centre.Often crop up in bulk on eBay, most run true just the odd ropy one but the prices they go for is usually pretty low

[lincolnshiremodeller]

One thing I'd add to this topic is that it is a worthwhile investment to buy a Kadee height gauge. I found this particularly useful because even when adding Kadee couplers to NEM sockets you are still making an assumption that the NEM socket is at the right height in the first place.

 

Different manufacturers look to have different tolerances. I found Bachmann coaches to be the worst with varying degrees of droop resulting in the Kadee uncoupling bar being too low and fouling paintwork. 

 

Simon 

[melmerby]

48 minutes ago, lincolnshiremodeller said:

One thing I'd add to this topic is that it is a worthwhile investment to buy a Kadee height gauge. I found this particularly useful because even when adding Kadee couplers to NEM sockets you are still making an assumption that the NEM socket is at the right height in the first place.

 

Different manufacturers look to have different tolerances. I found Bachmann coaches to be the worst with varying degrees of droop resulting in the Kadee uncoupling bar being too low and fouling paintwork. 

 

Simon 

There are at least 4 different height "NEM"* pockets on UK stock, with appropriate cranked tension locks to compensate. There are also at least two longitudinal positions affecting the relationship with the buffers, so there are also different length tension locks to compensate.

E.g the new Hornby GWR Prairie tank has different heights and different lengths front and back!

Fitting Kadee couplers means taking these variations into consideration.

Some Bachmann stock has a hugely cranked tension lock (typically 4 wheeled wagons introduced a few years ago.

As an example, I carve off the complete coupling mount and use a # 146 fitted to the underside of the floor.

 

*There is an NEM H0 spec, adopted by the DOGA for the NEM pocket position but the UK manufacturers (and others) have generally ignored it and do their own thing.

Edited August 9, 2020 by melmerby

[Butler Henderson]

Most Bachmann 4 wheel wagons can have the NEM mount eased down to the correct height and a appropriate piece of plastic card glued in place to stop it moving back upwards

[melmerby]

4 hours ago, Butler Henderson said:

Most Bachmann 4 wheel wagons can have the NEM mount eased down to the correct height and a appropriate piece of plastic card glued in place to stop it moving back upwards

You must have different wagons to me as on many of mine the mount is part of the floor moulding!

[Butler Henderson]

The actual socket is a push fit into the floor mounting

[melmerby]

This type need to drop approximately 2.5 - 3mm else the coupling is too high.

If you try dropping them enough for the Kadee to be the correct height, they wont stay in the dovetail mount.

I tried it last time you recommended it.

 

 

So they end up like this (#146 in gear box):

 

It's the perfect height glued to the undereside of the floor

I normally screw them in place but this one was stuck to see how it fares.

 

A little more work but the #146 is also cheaper than the NEM ones, the #146 I buy in bulk.

 

Edited August 10, 2020 by melmerby

[boxbrownie]

Not put any Kadees on Bachman wagons yet, but all the Dapol wagons I have the NEM sockets are spot on the correct height, makes it so much easier.

[melmerby]

3 hours ago, boxbrownie said:

Not put any Kadees on Bachman wagons yet, but all the Dapol wagons I have the NEM sockets are spot on the correct height, makes it so much easier.

I think Dapol have used a common mount for all their wagons which are fitted with coupling pockets, unfortunately Bachmann haven't.

The early conversions from fixed tension locks to NEM style pockets were as the one I posted above with about a 2-3mm step in the tension lock to compensate.

I have tried a few ways to do those, an NEM Kadee stuck directly to the underside of the incorrect height pocket is not far off but gluing the nylon type plastic reliably is difficult.

Butler Henderson's method didn't work for me as there wasn't enough of the pocket dovetail left in the receptacle to reliably keep it in place, I suppose some sort of adhesive might help.

I've got quite a lot of Bachmann product with the large plastic screw-on Tension Lock, carving is unavoidable on most of these, the same as the Mainline wagons they were derived from.

 

As in the picture above I ended up removing most of the old mount away and using a #146 whisker coupling which IMHO are better than the NEM mount ones anyway.

Hornby still have some wagons with a derivation of the old Airfix mount but some of these can be cobbled to take a NEM type Kadee.

Edited August 10, 2020 by melmerby

[steve1]

The other essential, to my mind, when using Kadees are their coupler trip pin pliers. OK they're not cheap but they will do the job properly and last forever.

 

https://www.kadee.com/ho-scale-tools-and-accessories-c-274_282_316/237-coupler-trip-pin-pliers-for-hon3-ho-s-on3-o-scale-couplers-p-328.htm

 

steve

 

[boxbrownie]

47 minutes ago, steve1 said:

The other essential, to my mind, when using Kadees are their coupler trip pin pliers. OK they're not cheap but they will do the job properly and last forever.

 

https://www.kadee.com/ho-scale-tools-and-accessories-c-274_282_316/237-coupler-trip-pin-pliers-for-hon3-ho-s-on3-o-scale-couplers-p-328.htm

 

steve

 

Must admit I persevered for a long time without and then a month ago a pair arrived in the post (had to order them and they took about six weeks to come)........the perfect tool for the job, so much easier to adjust very minutely and accurately.

 

Not cheap but will never wear out.

[ejstubbs]

3 hours ago, boxbrownie said:

Not put any Kadees on Bachman wagons yet, but all the Dapol wagons I have the NEM sockets are spot on the correct height,

 

Interesting.  I found that my Dapol wagons had much worse 'droop' than any of my Bachmann ones.  I was lucky enough never to encounter any of the Bachmann ones which simply had the NEM pocket at the wrong height, per melmerby's photos above - not just an variance in tolerances, but plain wrong.

 

Any 'droop' on my Bachmann wagons has been easily addressed with a shim of 10 thou plasticard in the NEM pocket either above or below the coupler's swallowtail.

 

The Dapol ones almost all seemed to droop a lot more, not helped by the fact that the Dapol NEM pocket actually seemed to be too long whilst also being too shallow - so, for example, the swallowtail on a Bachmann NEM coupler was a force fit in a Dapol NEM pocket because it was a tad too thick, but even forced fully home the catches on the end of the swallowtails of the Bachmann NEM coupler wouldn't engage with the back of the Dapol NEM pocket.  Partly for this reason I ended up getting rid of a number of my Dapol wagons; the ones I wanted to keep I converted to whisker couplers rather than NEM.  All this said, a couple of Dapol wagons I purchased more recently seem to take the Kadee NEM couplers without a problem, so maybe either Dapol have sorted out their NEM pockets or Dapol's NEM pockets and Bachmann's NEM couplers were at the very opposite extremes of what could be got away with under the guise of "tolerances".

[melmerby]

31 minutes ago, ejstubbs said:

 

Interesting.  I found that my Dapol wagons had much worse 'droop' than any of my Bachmann ones. 

That's true, they do droop but are nominally in the right place!

[boxbrownie]

19 hours ago, ejstubbs said:

 

Interesting.  I found that my Dapol wagons had much worse 'droop' than any of my Bachmann ones.  I was lucky enough never to encounter any of the Bachmann ones which simply had the NEM pocket at the wrong height, per melmerby's photos above - not just an variance in tolerances, but plain wrong.

 

Any 'droop' on my Bachmann wagons has been easily addressed with a shim of 10 thou plasticard in the NEM pocket either above or below the coupler's swallowtail.

 

The Dapol ones almost all seemed to droop a lot more, not helped by the fact that the Dapol NEM pocket actually seemed to be too long whilst also being too shallow - so, for example, the swallowtail on a Bachmann NEM coupler was a force fit in a Dapol NEM pocket because it was a tad too thick, but even forced fully home the catches on the end of the swallowtails of the Bachmann NEM coupler wouldn't engage with the back of the Dapol NEM pocket.  Partly for this reason I ended up getting rid of a number of my Dapol wagons; the ones I wanted to keep I converted to whisker couplers rather than NEM.  All this said, a couple of Dapol wagons I purchased more recently seem to take the Kadee NEM couplers without a problem, so maybe either Dapol have sorted out their NEM pockets or Dapol's NEM pockets and Bachmann's NEM couplers were at the very opposite extremes of what could be got away with under the guise of "tolerances".

That is very odd, all mine have been quite literally a two minutes job to change them over and check heights on the gauge, not had any issues with forcing them in or droop.......ooh....pardon me vicar