Self centering Keen systems close coupling units

[Bricky89]

I'm currently near completion of a project involving 5 Mk4 coaches and a old Hornby Mk2 BSO which involves fitting the rake with Kadee couplers as per what I am fitting to the rest of my working fleet.

 

The Mk4's are fitting with the very good Keen systems self centering units with resin side skirts to hide.

 

However I can't find a method which will self center the unit as the arms get stuck to one side after going around a corner, I did ask the guy from Keen systems at Doncaster show this year and the only reply I got was to bin the kadee's and go for the roco alternative. Which is not something I am prepared to do after now equiping about 50 coaches with Kadees and a similar amount of loco's/wagons.

 

Has anyone been able to self center these units?

[Bulleidboy]

Hello Bricky

 

I assume that you are using the "Close Coupling System" ie the one which can be adapted for many coaches rather than the one specifically for Bachmann Mk1 coaches.

 

I've used this on Bachmann Bulleid coaches and it is very effective. On a previous thread I posted that these units self-centred without the addition of any springing mechanism; you might find Adrian's reply interesting - this suggests that the self-centring only works with solid couplings (I use the dummy buckeyes provided by Roger Keen).

 

Regards

 

Mike

 

 

The mechanics of the mechanism and the bar coupler mean that close coupling mechanisms don't need self-centering when coupled. The self-centering is only there to return the coupling to centre when it isn't coupled, and so only needs the very light springs as seen in the RTR mechanisms (or the aftermarket ones by Fleischmann or Roco). This lack of self-centering under load is why using these mechanisms with couplers that don't create a solid bar (like Kadees or tension locks) can cause running problems with longer trains. It is also the reason why they work - if they agressively self-centered they would defeat the intent of the mechanism.

 

Adrian

[34theletterbetweenB&D]

...Has anyone been able to self center these (Keen) units?

Yes, by using any coupler system that makes a rigid link. That's the way they are designed to work, the re-centering force comes from the action of the rigid link. Adrian's analysis is correct, a light spring to recentre the system when it is not coupled up but which imposes little resistance to movement is desireable. Go to far with recentering spring tension, and the resistance to movement will force the vehicles off the rails as they transition from straight to curve.

 

That said when first trialling with the RTR vehicles from Hornby and Bachmann equipped with these close coupling systems, I found they will typically cope being pushed and pulled through any formation with miniature tension lock couplers, with up to four vehicles, despite the very poor recentering action provided by tension locks. I had made sure that the mechanisms were moving very freely and used some powdered graphite as a dry lubricant. That clearly was no good for my dozen coaches ambition, and I moved on to the Roco coupler within sets which perform perfectly. I didn't do any such trial with Kadee, but would expect it to do at least as well as tension locks, especially if a version with a rigid head on the shank is used (the hinged head on the NEM mounting Kadees is not required on camming mechanisms, a smidge of Araldite sorts that out). On the end of coach sets I have rigid head Kadee, and the camming mechanism works efficiently enough forward and reverse coupled onto locos which typically have a body mounted Kadee.

 

So if you are set on Kadee only, here's what I would suggest. Try using rigid head Kadee (I have no 5s straight into NEM pockets they should be adaptable to the Keen mounting with no trouble) and experiment with light recentering springs on the Keen units. If I could get four coaches to work with tension locks, it doesn't seem too much of a stretch to make a set of six work with Kadee, which in rigid head form does supply some recentering force.

[RFS]

Hello Bricky

 

I assume that you are using the "Close Coupling System" ie the one which can be adapted for many coaches rather than the one specifically for Bachmann Mk1 coaches.

 

I've used this on Bachmann Bulleid coaches and it is very effective. On a previous thread I posted that these units self-centred without the addition of any springing mechanism; you might find Adrian's reply interesting - this suggests that the self-centring only works with solid couplings (I use the dummy buckeyes provided by Roger Keen).

 

Regards

 

Mike

Hi there - only yesterday I made a start on using the Keen close-coupling on my Bulleid coaches but I've been having a bit of a problem with the first pair of coaches I attempted. It seems that once the bogies are refitted the tops of the wheels are touching the coupling mechanism which impedes both the the swing of the couplers and the bogies, and it lead to derailments on curves.

 

Did you have to take any special action to get these fitted properly on your Bulleid coaches?

 

Thanks

[Adrian Wintle]

Hi there - only yesterday I made a start on using the Keen close-coupling on my Bulleid coaches but I've been having a bit of a problem with the first pair of coaches I attempted. It seems that once the bogies are refitted the tops of the wheels are touching the coupling mechanism which impedes both the the swing of the couplers and the bogies, and it lead to derailments on curves.

 

The example on the Keen site shows that you have to cut away a bit of the floor and trim the triangular plate on the coupling arm into a T shape with the Bachmann Bullieds.

http://www.keen-systems.com/page5.html

 

Adrian

[Bricky89]

Ok, change of plan has taken hold now regarding the Mk4 set with Mk2 BSO.

 

The inner vehicles are now fitted with the Hornby version of Roco couplings and they work well on the Keen close coupling unit. With Kadee's fitted to the buffered end of the TSOE and brake end of the Mk2 BSO.

 

Also now brings into use a old Replica Mk1 RBR which was sidelined after completion of my Blue Pullman rake with newer Hornby coaches to be converted as a barrier coach with Kadee coupling at one end and roco coupler at the other.

 

Pictures of the completed coaches can be uploaded on request.

[RFS]

The example on the Keen site shows that you have to cut away a bit of the floor and trim the triangular plate on the coupling arm into a T shape with the Bachmann Bullieds. http://www.keen-systems.com/page5.html Adrian

 

Ah - thanks for that. Looks like a bit more bodging than I had anticipated ....

[RFS]

Hi all - I'm looking again at using these to close-couple my Bachmann Bulleids. I can see from the Keen website that you have to cut out a section of floor to fit these. What's the easiest way of doing this? Using a Dremel, perhaps, but if so what attachment would you use for that?

 

Thanks

[Adrian Wintle]

I usually drill holes allong the inside of the area I want to remove (manually or with the Dremel), cut the remaining webs with a craft knife or small saw (or a Dremel with a rotary cutter - the thing like a drill bit with long cutting edges), and then file to fit.

 

Adrian

[Pete Harvey]

I'm using the Keen system on my DBSO and carriages and I have had the same problem the way I got around it is to thin out the hook unit and run a file oner the mounting so there is more play between the parts of each unit and they work fine now.

 

 

I hope this helps you?

 

Pete

[RFS]

The problem with the Bulleid coaches is that the top if the unit fouls the wheels and causes derailments if you try to fit flush with the underside of the coach. Hence the way you are expected to install it is to cut out a section of the coach floor so that the unit is thus higher and clears the wheels. On other types of coach - and presumably yours - this isn't a problem so fitting the units is relatively straightforward.

[Jaggzuk]

How I fitted Keen Coupling System to four Bachmann/Mainline Collett coaches.  

 

These were some coaches where I had removed the original tension hook couplings (THC) a long time ago and so to get them running on out 8x4 layout, I decided to try out the Keen Close Coupling system.  I had a good chat with the supplier and got some handy hints from him.  I also had a good read of all the fitting instructions on the website.  The aim of this trial was to see how well they work on the layout which has R2 minimum radi and R4 maximum, 3% gradients and Peco medium streamline points on the main line.

 

The initial results are pleasing, but like all retrofit coupling systems, some fettling was required.

 

As I had removed the original couplings, I could not show a photo of what they were like with THC, but there is a really nice photo on this blog entry, which also shows an alternative way of reducing the gap and how to make gap filling gangway corridors  http://www.rmweb.co.uk/community/index.php?/blog/880/entry-10562-Bachmann-collett-coaches-%E2%80%93-bringing-them-closer/

 

I used these Keen fitting instructions http://www.keen-systems.com/Bachmann%20GWR%20Collett%20Coaches.html

 

Here are my steps photos.

 

The Keen kit parts and what I did to them.

 

A - Cut off the THC bar flush with the bogie side frames.

B - Added 0.75mm (30 thou) plasticard washer to raise the carriage body so the wheels to not hit the Keen unit.

C - Trimmed 1mm off each side of the base unit so that it fits inside the chassis side frames.  I also cut off the sole bar spaces lugs so that the unit face ended up 12mm from the buffer heads (as per Keen kit instructions)

D - Filled off all moulding flashing to create a smooth fish tail on the draw bar

E - Filled the gap under the location finger, this allows a much freer swing of the draw bar.

F - Reamed out the two holes so that the draw bar can easily be dropped on to the opposite two pronged draw bar.

 

The completed installed unit.  This was glued using two small drops of liquid melt (Metpak) glue

 

Coach end separation on an R2 curve

 

Close up on the R2 curve, Ok so this looks bad but the gap disappears on the straight track.

 

Top view showing reveres swing over a pair of turnouts

 

Close coupled on the straight, with buffers touching.  So the gap between the corridors cannot be reduced any further, so I may add home made paper corridor filler at a later date

 

One of the fettling issue to resolve is the couplings are quite noisy.  They creak quiet a lot as the the coaches navigate curves and turnouts at slow speed.  So I may try some dry grease on the draw bar fish tail to see what that does.  But in the main the result are very good and so I will definitely be doing some other rakes of coaches with old THC and big corridor gaps.

 

 

[Post edited to update the parts photo as wrong offcuts were shown}

[ejstubbs]

Useful post, thank you.  Can I check one thing?  In your first photo, relating to point C, am I right in thinking that the offcuts you've shown were actually cut off the opposite side of the base plate to the one they're lined up next to in the photo?

[Dunsignalling]

Ah - thanks for that. Looks like a bit more bodging than I had anticipated ....

It's a bit tedious but not difficult, I've done a couple of sets.

 

Just draw/scribe round the Keen base, on the top of the floor. Drill a chain of holes inside the line then join them up with a sharp knife. Finish off with files, ideally so the base is a snug fit in the aperture, that way you can just fix it in with solvent.

 

John

[Dunsignalling]

How I fitted Keen Coupling System to four Bachmann/Mainline Collett coaches.  

 

These were some coaches where I had removed the original tension hook couplings (THC) a long time ago and so to get them running on out 8x4 layout, I decided to try out the Keen Close Coupling system.  I had a good chat with the supplier and got some handy hints from him.  I also had a good read of all the fitting instructions on the website.  The aim of this trial was to see how well they work on the layout which has R2 minimum radi and R4 maximum, 3% gradients and Peco medium streamline points on the main line.

 

The initial results are pleasing, but like all retrofit coupling systems, some fettling was required.

 

As I had removed the original couplings, I could not show a photo of what they were like with THC, but there is a really nice photo on this blog entry, which also shows an alternative way of reducing the gap and how to make gap filling gangway corridors  http://www.rmweb.co.uk/community/index.php?/blog/880/entry-10562-Bachmann-collett-coaches-%E2%80%93-bringing-them-closer/

 

I used these Keen fitting instructions http://www.keen-systems.com/Bachmann%20GWR%20Collett%20Coaches.html

 

Here are my steps photos.

 

The Keen kit parts and what I did to them.

Parts A.JPG

 

A - Cut off the THC bar flush with the bogie side frames.

B - Added 0.75mm (30 thou) plasticard washer to raise the carriage body so the wheels to not hit the Keen unit.

C - Trimmed 1mm off each side of the base unit so that it fits inside the chassis side frames.  I also cut off the sole bar spaces lugs so that the unit face ended up 12mm from the buffer heads (as per Keen kit instructions)

D - Filled off all moulding flashing to create a smooth fish tail on the draw bar

E - Filled the gap under the location finger, this allows a much freer swing of the draw bar.

F - Reamed out the two holes so that the draw bar can easily be dropped on to the opposite two pronged draw bar.

 

The completed installed unit.  This was glued using two small drops of liquid melt (Metpak) glue

Fitted.JPG

 

Coach end separation on an R2 curve

R2 curve 1.JPG

 

Close up on the R2 curve, Ok so this looks bad but the gap disappears on the straight track.

R2 curve 2.JPG

 

Top view showing reveres swing over a pair of turnouts

Rev Curve.JPG

 

Close coupled on the straight, with buffers touching.  So the gap between the corridors cannot be reduced any further, so I may add home made paper corridor filler at a later date

Straight.JPG

 

One of the fettling issue to resolve is the couplings are quite noisy.  They creak quiet a lot as the the coaches navigate curves and turnouts at slow speed.  So I may try some dry grease on the draw bar fish tail to see what that does.  But in the main the result are very good and so I will definitely be doing some other rakes of coaches with old THC and big corridor gaps.

1. Bogie modification. It's not essential to cut the whole end out, which sometimes causes the wheels to come loose after a while.. You can just cut a slot in the flat part a bit wider that the Keen drop arm/channel and it'll all coexist happily*.  If they do interfere with one another, widen the slot a bit more.

 

*EDIT: this will also self-centre the Kadee sufficiently to function as intended.

 

2. Creaking. The best lubricant is a 6B pencil, rubbed over any surface that slides against another.

 

Hope this helps.

 

John

[Jaggzuk]

Useful post, thank you.  Can I check one thing?  In your first photo, relating to point C, am I right in thinking that the offcuts you've shown were actually cut off the opposite side of the base plate to the one they're lined up next to in the photo?

 

Good obs ejsubbs.  I must have picked up the wrong bits up on my workbench for the photo, thats late night working for you ;-)

 

I have edited the post and updated the photo.

[Dunsignalling]

Hi all - I'm looking again at using these to close-couple my Bachmann Bulleids. I can see from the Keen website that you have to cut out a section of floor to fit these. What's the easiest way of doing this? Using a Dremel, perhaps, but if so what attachment would you use for that?

 

Thanks

I personally wouldn't use a powered cutting tool for this. The plastic is quite soft and melts readily if the drill speed is too high. It will be very easy to take out a lot more than intended.

 

John

[Jaggzuk]

OK things have not quite work out perfect for my first conversion. 

 

It would turn out that when the coaches go round corners on the layout, the wheels are in fact rubbing on the draw bar delta plate (part D in my previous photo).  I had not noticed this originally when testing a pair of coaches, as the loco I initially used to test the the couplings had very good tractive effort (Class 20) and pulled them round without an issue.  But now I have the full 4 coach rake formed and using a Standard 4MT steam loco, it is very obvious as it struggles to pull them round the curves on the gradients.

 

I modified the draw bar delta plates as per Keen instructions http://www.keen-systems.com/Bachmann%20GWR%20Collett%20Coaches.html for one of the coaches, but on R2 and R3 curves the wheel still rub.  So for now the only simple solution has been to swap the 14.1mm wheels with 12.6 wagons wheels and this has solved the issue.  So I can either keep these wheels, or will have to add a thicker spacer washer on the bogie, but this then means that pivot pin does not lock in to the chassis and the gap between the coach and bogie looks a bit too big. The only other way I can see would have been to cut the floor out and to sit the Keen base unit into the chassis, but that is big messy work.

 

So a bit of a negative issue really on the couplings.  To me, the single universal type kit does look like it needs a lot of bodging to fit different coaches.  But I do have to say once working (on smaller wheels) the close coupling is very good and looks great, so I shall persevere to work it out.

[TRAILRAGE]

Cutting out a section of the chassis and fitting it level was how I did it on my Lima Super GUV's. These in turn were fitted with Commonwealth bogies with 14mm Romford wheels but does take a bit of trial and error until you get a perfect fit. The only problem I had with them is they seem to go Brittle after a few years (must be 15 or so years give or take a few since I did mine) and the coupling pockets have all snapped off the cams 

 

Have tried several but they don't seem to take to being glued so have taken them off leaving just the baseplates behind and are now Temporary using bogie mounted couplings until I get round to either shouting and swearing at them or just junk the lot and use Kaydee No 5 mounted to the chassis.

 

Cheers Trailrage.

 

As an aside my fathers one seem to be OK at the mo after 5-10 years sporadic use.

[Dunsignalling]

I'm currently near completion of a project involving 5 Mk4 coaches and a old Hornby Mk2 BSO which involves fitting the rake with Kadee couplers as per what I am fitting to the rest of my working fleet.

 

The Mk4's are fitting with the very good Keen systems self centering units with resin side skirts to hide.

 

However I can't find a method which will self center the unit as the arms get stuck to one side after going around a corner, I did ask the guy from Keen systems at Doncaster show this year and the only reply I got was to bin the kadee's and go for the roco alternative. Which is not something I am prepared to do after now equiping about 50 coaches with Kadees and a similar amount of loco's/wagons.

 

Has anyone been able to self center these units?

I'm not familiar with the bogies in question, but suggest you fix two pieces of wire into the ends to steer the CCU.

 

Unless you are intending to regularly split and reform your coaches "on stage" the best performance will come from using Kadees just at the outer ends of the set and Rocos in between.

 

John

[Phil Bullock]

Have put close coupling mechanisms on two Replica Mark 1s

 

One with modified Keen systems - but this recreation of the Bachmann system works better

 

 

Not  apparent here - outer edge of bogie top is profiled and the coupling fish tails sit just below it giving a positive engagement. Bit of work required but nothing too serious! Might it work on later marks of carriage?

 

Phil

 

[Dunsignalling]

OK things have not quite work out perfect for my first conversion. 

 

It would turn out that when the coaches go round corners on the layout, the wheels are in fact rubbing on the draw bar delta plate (part D in my previous photo).  I had not noticed this originally when testing a pair of coaches, as the loco I initially used to test the the couplings had very good tractive effort (Class 20) and pulled them round without an issue.  But now I have the full 4 coach rake formed and using a Standard 4MT steam loco, it is very obvious as it struggles to pull them round the curves on the gradients.

 

I modified the draw bar delta plates as per Keen instructions http://www.keen-systems.com/Bachmann%20GWR%20Collett%20Coaches.html for one of the coaches, but on R2 and R3 curves the wheel still rub.  So for now the only simple solution has been to swap the 14.1mm wheels with 12.6 wagons wheels and this has solved the issue.  So I can either keep these wheels, or will have to add a thicker spacer washer on the bogie, but this then means that pivot pin does not lock in to the chassis and the gap between the coach and bogie looks a bit too big. The only other way I can see would have been to cut the floor out and to sit the Keen base unit into the chassis, but that is big messy work.

 

So a bit of a negative issue really on the couplings.  To me, the single universal type kit does look like it needs a lot of bodging to fit different coaches.  But I do have to say once working (on smaller wheels) the close coupling is very good and looks great, so I shall persevere to work it out.

It may be a bit messy, but it's not a big job. I did a Bachmann Bulleid underframe last week (just one, s/h, to replace a damaged one in an existing set) and it took barely ten minutes to do each end. Cutting the hole takes moments but be very careful if you use a power tool and keep the speed as low as possible, the plastic is surprisingly soft and melts easily.  Most of the time was spent cleaning up the edges and making the unit a snug fit - I like my stock to look presentable even from underneath.

 

You also need to narrow the CCU to fit between the solebars - I have a nice big coarse file but it will take a while if you only have gentle ones.

 

I re-used the Romford wheels from the coach being overhauled, which are a tad smaller than r-t-r wheels and have shallower flanges, too. I only needed to remove the portion of floor closest to the bogie mount that comes a bit lower than the rest, and the moulded pipe detail on the outer section. I found the flanges just marked the edges of the delta plate so I did take a bit out of that, though not as much as shown in the instructions.  

 

I did some Replica Colletts a while ago and you do need to recess the whole unit on those, even with the finer wheels.

 

Hope this helps

 

John