Kadee Couplers

[Dunsignalling]

Suzie's advice to lubricate the interface between the CCU and the underside of the coach is extremely pertinent (in hindsight I should have mentioned it in my earlier post) but don't use oil. 

 

The best thing is to give the underside of the floor a good scribble with a soft graphite pencil - 4B or softer. I use a 6B but these seem quite hard to get these days.

 

I use it on the inside of Kadee draft boxes, too.

 

EDIT: 6B pencils still seem to be readily available from more specialist stationers/art suppliers and via the web. 

 

John  

Edited December 5, 2016 by Dunsignalling

[Dunsignalling]

The issue with the 'close coupling' mechanisms is that when going from curved track to straight track the spring in the mechanism is required to pull the coupling in. This is working against the train trying to pull it out so the coupling does not easily return to the straight position, and there is therefore a side force on the bogie twisting it. This side force is enough to force two of the flanges against the rails and therefore it is likely that at least one rides up on the straight. Adjusting spring tension may help, as may lubrication of the close coupling mechanism (these usually have a lot of sliding face area). The spring tension required will vary depending on where the vehicle is in the train of course with a heavier spring required at the front of the train.

 

If the problem is marginal adjusting the back to backs to the max might help by eliminating the ability of the bogie to turn within the gauge.

 

Kadees should be body mounted rather than bogie mounted (Talgo mounted in Kadee language I think) and this will eliminate the problem (in terms of if the mechanism does not return to straight there will be no turning force on the bogie), but if you want to retain close coupling you will probably have to completely re-engineer the mechanism.

 

This effect can be clearly observed at slow speed when you will see that on returning to straight track the gap does not close up completely and the coupler arm remains to one side rather than straight.

Any "not-straightening-up" issues are banished if the CCUs are joined by a rigid link or non-flexible coupler heads like Roco or Fleischmann.

 

The CCU shouldn't have any direct effect on the action of the bogie anyway as the two won't be in contact if set up properly. In that sense a CCU mounted coupler should behave the same as a solidly body-mounted one. The real problem lies in coach-to-coach interaction when using NEM Kadees mounted in CCUs; the double pivot just allows too much movement.   

 

The end coupled to the loco should be firmly pulled back into line by the rigidly mounted Kadee on the tender whilst (in my experience) Talgo mounted couplers on locos are much more likely to derail the bogie or truck to which they are fixed than a coach, which will have a considerably greater mass.

 

John

Edited December 5, 2016 by Dunsignalling

[Dominion]

I have had many of the issues described here and used many of the suggestions suggested by others and found they work. 

The issue happening near the front of the rake suggests to me that the issue Suzy describes is what is happening.

I used fixed link couplings where I can in the rake and they work extremely well.

I too alternate Roco and Hornby/Roco style on my Hornby Gresley coaches. I am sure you will have some of the Hornby versions around as they come with several different coaches. I suggest you try them to see if it fixes it.

 

The issue was worse for me on Hornby's Pullman's than on the Gresleys.  I suspect this is because of the extra force transmitted through the couplings at the front of the rake from the fiction of wheel pick ups further back int he rake, and worse after a curve on an up gradient.  This all fits with the "coupler tension preventing centring" failure mode described earlier.

 

I have also used powered graphite as suggested above in some sticky close  coupling mechanisms to good effect.

 

With Kadees themselves on Hornby Gresleys, I have found some sit at the right height and some sag. Normally just packing a thin piece of card under the Kadee in the NEM coupling box is enough.  

I use Kadee 19s at the end of rakes and on coaches that will be attached or detached, (32 inch minimum curves).

 

Tom

[ejstubbs]

The CCU shouldn't have any direct effect on the action of the bogie anyway as the two won't be in contact if set up properly. In that sense a CCU mounted coupler should behave the same as a solidly body-mounted one. The real problem lies in coach-to-coach interaction when using NEM Kadees mounted in CCUs; the double pivot just allows too much movement.

 

I agree with this.  I think that my approach of immobilising the pivoting coupler head (see post #312 above) goes some way to alleviating this problem, but there is still rather too much flexibility between the CCUs due to the lack of a rigid connection between the coupler knuckles.  So it can help in some circumstances, but it's far from a foolproof solution.

 

The end coupled to the loco should be firmly pulled back into line by the rigidly mounted Kadee on the tender whilst (in my experience) Talgo mounted couplers on locos are much more likely to derail the bogie or truck to which they are fixed than a coach, which will have a considerably greater mass.

 

This is definitely true for the front pony truck on my 2-6-4T, if the Kadee coupling is mounted rigidly.  If the Kadee coupling can swing freely in a gear box then the pony truck doesn't derail when hauling stock round 2nd radius curves while travelling bunker first.  If propelling stock travelling smokebox first, though, the coupling tends to 'collapse' sideways towards the outside of the curve, reducing the distance between the loco and the coach (so increasing the likelihood of buffer lock) and generally messing up the close coupling.  I hadn't actually thought of mounting the coupling on the buffer beam (duh!) - that'll go on the list of things to experiment with.

 

The loco's rear bogie behaves OK with a gear box mounted, free-swinging long shank coupling installed, both hauling and propelling.   I suspect that this is because the bogie is on a sliding attachment to the loco chassis rather than a simple pivot, and because with two axles it's less prone to being twisted off the rails anyway.  (I might still experiment with mounting the rear Kadee to the loco chassis rather than the bogie, though, just to see.)

 

UPDATE: It doesn't look possible to fit the front coupling under the buffer beam of the 2-6-4T, due to the risk of it fouling the pony truck wheels on my 2nd radius curves.  However, I did find that the wheels on both the pony truck and the rear bogie were quite a long way under gauge.  Correcting that seems to cure their tendency to derail when propelling coaches, with the Kadee rigidly mounted.  Touch wood everything is now working OK.

Edited December 6, 2016 by ejstubbs

[ejstubbs]

Update on my experience with Kadees on my Hornby 2-6-4T: It doesn't look possible to fit the front coupling under the buffer beam of the 2-6-4T, due to the risk of it fouling the pony truck wheels on my 2nd radius curves.  However, I did find that the wheels on both the pony truck and the rear bogie were quite a long way under gauge.  Correcting that seems to cure their tendency to derail when propelling coaches, with the Kadee rigidly mounted.  Touch wood everything will now continue to work OK!

[gwrrob]

http://pandhmodels.com/

 

I see my usual port of call for reasonable priced Kadees has closed down.Anyone know what happened here and can recommend an alternative supplier please.

[ejstubbs]

Don't know what's happened to P&H - they were up and running a week or so back IIRC.  Hopefully it is just site maintenance as they say.

 

Try DC Kits for Kadees in the mean time.

[charliepetty]

Don't know what's happened to P&H - they were up and running a week or so back IIRC.  Hopefully it is just site maintenance as they say.

 

Try DC Kits for Kadees in the mean time.

 

P&H have closed down, so the website should remain closed.   DC kits do have a vast stock of kadee couplings, well worth trying.  

[melmerby]

The issue with the 'close coupling' mechanisms is that when going from curved track to straight track the spring in the mechanism is required to pull the coupling in. This is working against the train trying to pull it out so the coupling does not easily return to the straight position, and there is therefore a side force on the bogie twisting it. This side force is enough to force two of the flanges against the rails and therefore it is likely that at least one rides up on the straight. Adjusting spring tension may help, as may lubrication of the close coupling mechanism (these usually have a lot of sliding face area). The spring tension required will vary depending on where the vehicle is in the train of course with a heavier spring required at the front of the train.

 

Further investigation suggest this may be the problem.

I have noticed that the errant wheel is trying to lift against a sideways force and is finally knocked off course by a slight "snap" action in the CCU as it belately returns to the straight position.

It always happens on the second or third coach of a 6 coach rake, whichever order they are in. Presumably it is the amount of tension in the CCU, which is less the further back you get.

 

The coaches seem to work fine if pushed through the same curve when the buffers take the driven force.

There is definitely no buffer locking in the forward direction and the corridor connexions are clear of one another.

 

Cheers

 

Keith

[Dungrange]

Don't know what's happened to P&H - they were up and running a week or so back IIRC.  Hopefully it is just site maintenance as they say.

 

The last post in the thread below indicates that the previous owners sold the business and attended their last show in November 2016.  Unfortunately I know nothing more.

http://www.rmweb.co.uk/community/index.php?/topic/62662-p-h-models/?p=2497313

[brian777999]

So now that I have the Triang coaches sorted I am going to move onto some GWR brake vans. I have some old Mainline GWR brake vans with the awful plastic wheels so I can practise on them... no harm done if I butcher these. Some people use the NEM #19 and #20 Kadees by just screwing them straight into the hole that is left after the tension lock coupler has been removed. That will work after removing some of the plastic but does the Kadee operate correctly if fitted this way ie. isn't the Kadee supposed to have a bit of sideways movement ?

 

I was thinking of cutting away all that plastic under the old couplers and fitting a 141 or 146 with a draft box to the floor of the vans. It means more work but would look a lot neater. The long 141/146 couplers are a bit too long but I think the medium 147/148 couplers would be too short. I think I can move the draft box of the 141/146 couplers back a little bit by cutting of the ''lip'' from the top of the draft box lid.

Edited December 7, 2016 by brian777999

[ejstubbs]

So now that I have the Triang coaches sorted I am going to move onto some GWR brake vans. I have some old Mainline GWR brake vans with the awful plastic wheels so I can practise on them... no harm done if I butcher these. Some people use the NEM #19 and #20 Kadees by just screwing them straight into the hole that is left after the tension lock coupler has been removed. That will work after removing some of the plastic but does the Kadee operate correctly if fitted this way ie. isn't the Kadee supposed to have a bit of sideways movement ?

 

I was thinking of cutting away all that plastic under the old couplers and fitting a 141 or 146 with a draft box to the floor of the vans. It means more work but would look a lot neater.

 

The NEM Kadees have an extra pivot at the end of the coupler shaft, so that the whole coupler head can rotate.  This goes some way to mitigating the loss of sideways movement in the coupler mount.  Bear in mind that a lot of US HO stock, which is what Kadees are designed for, have the NEM pocket moulded in to the buffer beam or otherwise rigidly fixed to the vehicle chassis.  IMO it's still not as effective as a flexibly mounted NEM pocket like the Bachmann and Hornby system, with the wedge-shaped connector to the chassis and the bendy link to the NEM pocket itself (I won't dwell on Dapol's rather inelegant implementation).  However, I believe that a screwed on NEM coupling is better than screwed on #5, which gives no sideways movement at all.

 

However, per something Dunsignalling said above, and in accordance with my findings with my 2-6-4T, a rigid mounting (albeit to a pony truck, bogie or tender) does sometimes seem to be beneficial on locomotives.  I do use a #5 screwed to the tender on some of my locos and it seems to work OK.  So for a longer wheelbase vehicle like a brake van I think it might be OK.  You might find that you need some packing between the coupling and the chassis to get the height right, though (somehow #5s seem to have a magical ability to be the right height when screwed directly to loco tenders!)

 

In the case of your brake vans, if it were me I would try to fit #14x series whisker couplers in gear boxes.  Yes, it does require more surgery to the underside of the vehicle but the result is better IMO.  Bear in mind that if the space constraints mean that the standard #242 gear box (which is supplied with the #14x series couplers) won't easily fit, then there two other types of gear box available: the #252 which is shorter (I use these on loco pony trucks and bogies) and the #262 which is narrower.  The #14x series of couplers are also available in three different lengths and three different coupler head heights on the shaft, so there is quite a bit of scope to play around to get something to fit.  I bit the bullet and invested in a stock of long & medium couplers of each height, plus the shorter & narrower gear boxes, so I can experiment freely without having to wait for supplies of the required component to come through the post.

 

My preference when fitting gear boxes is, where feasible, to use a machine screw in a tapped hole, rather than a self-tapper.  IIRC Mainline used a solvent-resistant plastic for the underframes so if you have to resort to glueing then I'd suggest canopy glue, which is less permanent than solvent cement anyway, while still being quite strong enough.

Edited December 7, 2016 by ejstubbs

[ejstubbs]

I have noticed that the errant wheel is trying to lift against a sideways force and is finally knocked off course by a slight "snap" action in the CCU as it belately returns to the straight position.

 

Come to think, I did experience something a bit like this with my Airfix non-corridor coaches.  On these, the lower end of the brake pipe projects no more than 1mm (more like 0.5mm I think, though I've not actually put a ruler next to it) below the buffer beam.  My first attempt at Kadee-ifying the couplings on the bogies left the Kadee coupler shaft just clear enough of the buffer beam for the two not to interfere - but I'd forgotten about the projecting end of the brake pipe.  Coming off a curve, the coupler shaft would catch very slightly on the brake pipe: sometimes with no ill effect, sometimes just enough to derail the bogie.  It took me an age to work out what was going on; only when I noticed the very faint "click" as the coupler shaft flicked past the end of the brake pipe did the light begin to dawn.

 

The solution in that case was to lower the mounting point for the coupler gear box, and use an underset coupler to bring the coupler head back up to the correct height.  (A more brutal solution would have been to trim off the offending fraction of the brake pipe, of course.)

 

It always happens on the second or third coach of a 6 coach rake, whichever order they are in. Presumably it is the amount of tension in the CCU, which is less the further back you get.

 

That sounds like a bit of graphite lubricant on the CCUs might indeed help to free them up a bit.  I have a small puffer bottle of powdered graphite at home, originally sold for use as a lubricant for security locks.  Kadee do powdered graphite in a 5.5g tube, under the IMO somewhat distasteful (and certainly misleading) name of "Greas-em".

Edited December 7, 2016 by ejstubbs

[Dunsignalling]

So now that I have the Triang coaches sorted I am going to move onto some GWR brake vans. I have some old Mainline GWR brake vans with the awful plastic wheels so I can practise on them... no harm done if I butcher these. Some people use the NEM #19 and #20 Kadees by just screwing them straight into the hole that is left after the tension lock coupler has been removed. That will work after removing some of the plastic but does the Kadee operate correctly if fitted this way ie. isn't the Kadee supposed to have a bit of sideways movement ?

 

I was thinking of cutting away all that plastic under the old couplers and fitting a 141 or 146 with a draft box to the floor of the vans. It means more work but would look a lot neater. The long 141/146 couplers are a bit too long but I think the medium 147/148 couplers would be too short. I think I can move the draft box of the 141/146 couplers back a little bit by cutting of the ''lip'' from the top of the draft box lid.

The back half of the 242 box isn't occupied when using whisker couplers so it's OK to take a bit off that end to get the pivot point further under the vehicle and ensure the long couplers aren't too long.

 

John

[Pacific231G]

The NEM Kadees have an extra pivot at the end of the coupler shaft, so that the whole coupler head can rotate.  This goes some way to mitigating the loss of sideways movement in the coupler mount.  Bear in mind that a lot of US HO stock, which is what Kadees are designed for, have the NEM pocket moulded in to the buffer beam or otherwise rigidly fixed to the vehicle chassis.  IMO it's still not as effective as a flexibly mounted NEM pocket like the Bachmann and Hornby system, with the wedge-shaped connector to the chassis and the bendy link to the NEM pocket itself (I won't dwell on Dapol's rather inelegant implementation).  However, I believe that a screwed on NEM coupling is better than screwed on #5, which gives no sideways movement at all.

 

In principle a Kadee coupler shouldn't work at all, at least not its delayed coupling mode, without some relative sideways movement of the two coupler heads but if you don't have room for the standard gear box there are more compact ones like the #252 and  #233 gear boxes similar to the rather older one on the left hand wagon below.

The right hand wagon, which is a modern Piko model, is fitted with NEM boxes in a close coupling unt and you can see that they are smaller.

 

It's worth exploring the Kadee website  http://www.kadee.com and their catalogue and primer are both available as pdf downloads.

I've tried Bachman EZmate couplers that have a solid shank (without the articulation incorporated in Kadee NEM263 couplers)  in some wagons retrofitted with fixed NEM boxes and the results were very unsatisfatory. I assume that all of Bachman's NEM boxes are in close coupling units so do have sideways movement  

 

Note that the standard NMRA draft gear boxes, moulded into the chassis of most US stock and also supplied separately by Kadee and others, are NOT the same as NEM pockets. Apart from being at a different height - the scale height of a real North American draft gear box-   they also allow room for a centring spring arrangement of some sort and have a separate lid that is snapped or screwed to the body after the coupler shank has been inserted. Because US stock doesn't have side buffers, close coupling is less of an issue though the standard Kadee couplers come with short medium and long shanks.

 

NEM  boxes on the other hand are usually a single moulding of an open box into which the swallow tail of a standard NEM coupler shank is a tight fit and locks into place so the coupler is a rigid mount in the box. This as you say is why the extra articulation is fitted.

Edited December 11, 2016 by Pacific231G

[melmerby]

 

 

That sounds like a bit of graphite lubricant on the CCUs might indeed help to free them up a bit.  I have a small puffer bottle of powdered graphite at home, originally sold for use as a lubricant for security locks.  Kadee do powdered graphite in a 5.5g tube, under the IMO somewhat distasteful (and certainly misleading) name of "Greas-em".

I have now replaced the #18s with Roco close couplers instead. They seem to space the coaches about the same but there are no derailments. However there is still a "jerk" after the coaches have come off a curve but not enough to throw the wheels off.

Looks like some work on the CC device on the coaches is required to make them smoother in action.

 

Currently fitting some NEM pockets to some Lima Siphon bogies so that I can try the #18s in them!

 

Keith

[brian777999]

Moving on to some wagons : I have two Mainline GWR brake vans with the awful plastic wheels ; even Hornby metal wheels do not run much better. I thought I would try cutting these up so that Kadees can be fitted and if I make a mess of it then no great loss. The large lump of plastic to which the tension lock coupler must  be removed first. The plastic on these wagons is very hard and it does not cut easily with a craft knife unlike the plastic on the Triang bogies. I drilled about 6 holes in the piece I wanted to remove then cut it away with a small cutting wheel on the Dremel tool. A small grinding wheel got closer to the base and finally a flat file so that the draft box can sit flush against the underside of the floor. I cut the lip off the top of the draft box so that it would sit against the underside of the floor. I am using a Kadee 146 and  this seems to have worked out quite well.  I think a 148 would also work if it was moved closer to the end of the wagon then the lip of the draft box would not have to be removed. I was able to drill into the base of the wagon and hold the draft box in place with a M2X6mm socket cap.

 

I have never been so glad of molded  hand rails ... imagine trying to hold the wagon if the hand rails were not molded  !

 

 Do these wagons come apart at all ? I was thinking of fitting windows but I could not pry anything apart.

Edited December 8, 2016 by brian777999

[Dunsignalling]

Moving on to some wagons : I have two Mainline GWR brake vans with the awful plastic wheels ; even Hornby metal wheels do not run much better. I thought I would try cutting these up so that Kadees can be fitted and if I make a mess of it then no great loss. The large lump of plastic to which the tension lock coupler must  be removed first. The plastic on these wagons is very hard and it does not cut easily with a craft knife unlike the plastic on the Triang bogies. I drilled about 6 holes in the piece I wanted to remove then cut it away with a small cutting wheel on the Dremel tool. A small grinding wheel got closer to the base and finally a flat file so that the draft box can sit flush against the underside of the floor. I cut the lip off the top of the draft box so that it would sit against the underside of the floor. I am using a Kadee 146 and  this seems to have worked out quite well.  I think a 148 would also work if it was moved closer to the end of the wagon then the lip of the draft box would not have to be removed. I was able to drill into the base of the wagon and hold the draft box in place with a M2X6mm socket cap.

 

I have never been so glad of molded  hand rails ... imagine trying to hold the wagon if the hand rails were not molded  !

 

 Do these wagons come apart at all ? I was thinking of fitting windows but I could not pry anything apart.

The Mainline Toads do come apart but it can be a bit tricky.

 

First, the whole body comes off, released by pushing the clips you can see in the photos to align with the holes. You may need to insert a thin blade between underframe and floor to part any glue but that used by Mainline has generally deteriorated enough to make this fairly easy.

 

Once the body is off, the floor needs to come out. Again, the glue on many has succumbed to the ravages of time but you may to run a scalpel round the joint to free it.

 

Then flex the body by trying to twist it and one corner should pop out far enough to get a small screwdriver blade in to complete the process. If not, drill a small hole in the middle of the floor and insert a self tapping screw to give something to pull.

 

This process, in my experience, doesn't work on Bachmann-made examples of this model - the floor is very securely fixed. I gave up on the BR bauxite version I purchased to "make the pair" with my old grey one, sold it on at a profit (Bachmann brakes of any kind were pretty much unobtainable new at the time) and was lucky enough to acquire a mint/boxed Mainline equivalent at a swap-meet for less than half what I got for it.   

 

Mine now have Alan Gibson wheels and they run faultlessly.

 

John

Edited December 8, 2016 by Dunsignalling

[Butler Henderson]

Moving on to some wagons : I have two Mainline GWR brake vans with the awful plastic wheels ; even Hornby metal wheels do not run much better. I thought I would try cutting these up so that Kadees can be fitted and if I make a mess of it then no great loss. The large lump of plastic to which the tension lock coupler must  be removed first.

Alternatively leave the "lump", drill a suitable hole in a 20 and screw fit in place with the screw that held the tension lock coupling in place.

Edited December 8, 2016 by Butler Henderson

[brian777999]

Butler : yes, I originally did that but I did not like the look of it. That is why I tried the 146 as it looks much neater.

[Butler Henderson]

All goes to show there are at least two ways to Kadee most stock!

[melmerby]

I have now replaced the #18s with Roco close couplers instead. They seem to space the coaches about the same but there are no derailments. However there is still a "jerk" after the coaches have come off a curve but not enough to throw the wheels off.

Looks like some work on the CC device on the coaches is required to make them smoother in action.

 

Currently fitting some NEM pockets to some Lima Siphon bogies so that I can try the #18s in them!

 

Keith

Following on from this I decided to try alternating Hornby/Roco couplings as recommended early in the thread.

The coaches now behave flawlessly but with the 'disadvantage' of a slightly bigger gap between corridor ends when on the straight.

Some #18s now fitted to the loco and leading coach without a problem.

 

I have noticed that the CCU on the Gresley corridor coaches lets the NEM pocket sag a bit which I assume causes the pin to foul the running rails.

The CCUs on the Stanier and Collett coaches are both slightly different (and from each other) and do not sag so much.

I am now trying #18s on the Staniers to see how they do there.

It's all a learning curve at the moment!

 

Being a tight wad I have made my own height gauge which has an NEM pocket one end and a Kadee #5 the other to help me on the way.

 

Keith

Edited December 10, 2016 by melmerby

[BR60103]

There are a couple more gauges that would be useful.

One is for the height of the top of a #5 box. The N scale gauge used to have a pointed lip at one end for marking this.

A gauge for the height of the NEM box.

One of the Platelayers made a device to measure the height of the floor or mounting pad from rail level.

 

 

 

 

Hole in board through the sleepers. Flat plate across rails. Vernier calipers rod through hole to measure.

[melmerby]

Moving on to some wagons : I have two Mainline GWR brake vans with the awful plastic wheels ; even Hornby metal wheels do not run much better

That's interesting.

I have some Mainline wagons and they run nicely on their original all plastic wheelsets, however I am changing all wheels on my rolling stock to metal as I need resistive wheelsets.

An early Bachmann Toad in virtually "as received from Mainline" condition has metal wheels on plastic axles in the same style as the split chassis locos (and it also has the large Mainline type tension lock)

Another slightly later one has the normal insulated metal wheels on metal axle type.

 

Keith

 

EDIT

BTW have you checked the axle lengths?

The lengths are not standardised, maybe the Hornby wheelsets are longer/shorter than the original?

Or try some Alan Gibson wheelsets?

Edited December 11, 2016 by melmerby

[brian777999]

For anybody who is interested I have just built a number of Ratio GWR wagons (563,564,565,569) and like the Hornby and Mainline Toad brake vans, I have found the Kadee 146 (long, centre set) to be a good fit. It is a pity they do not make the 146 in a bulk pack as I will be needing a lot of these.

 

Weathering : If weathering wagons with an airbrush do you remove the Kadees first ? I am a bit worried about that very small exposed spring.