Kadee Couplers

[Jaggzuk]

You could also try 2 rows of 3mm cube magnets between the sleepers.  See my ramblings and trials on this http://www.rmweb.co.uk/community/index.php?/topic/106602-family-8x4-oo-layout-trains-running-again/?p=2878762

 

The two key things to note are:

1. The longer the magnet zone is, the less accurate you have to be when performing and uncouple action.
2. The higher the N## number is the stronger the Neodymium Magnets will be (and more expensive).  N35-N42 will be fine for Kadee from my trial.  If too strong the magnet will pull the wagon coupling. N50 will most likely be too strong an effect.

Always mark up the magnet poles when working with rows as this is key in their correct placement es

 

Use superglue to fix and one row at a time.

 

Try to ensure uncouple zones are on straight track.

 

Hope this helps.

[Budgie]

The kadee magnets are rather large and need more installation work. The smaller kadee magnet needs to be cut into the sleepers, and is not very powerful, and the larger under track one needs a fairly large cut into the baseboard making retro fitting a pain.  These are easier to install and less obtrusive once painted over. I will conduct more trials on the layout over the coming months.

I fixed a few Kadee 321s into code 100 track, and a few 322s in code 75, track using some UHU-type glue. The procedure was simple and needed no special installation work at all.

[Butler Henderson]

If you are using some form of trackbed between the track and the baseboard that may overcome the need to cut a hole in the baseboard to use the undertrack magnets - as I have commented before I identify the location of undertrack magnets by a bird on a nearby structure

[ejstubbs]

If the magnets are that powerful that they cause those issues, isn't a case of over engineered for the task? Why not stick with the Kadee versions?

Simpler to use smaller neodymium magnets. My first thought when I read NoelG's post was that his magnets sounded a tad on the large side. My experiments to date have been quite successful with 3mm diameter magnets, which fit nicely between Peco code 100 sleepers and are still quite strong enough to do the job.

 

IIRC, somewhere in the Camel Quay layout thread is a video of one-way uncoupling using a single neo magnet adjacent to one rail.

[DutyDruid]

Hi All

 

I have been doing some "upgrading" to the Fareham Club's layout Nictun Borrud http://fareham-mrc.org.uk/layouts/nictun-borrud/ and have been experimenting with Kadee couplings in remote uncoupling mode - I have to say with some initial success.

 

However, we've taken the layout to the show at Arundel today, for the first time with all the goods wagons fitted up - and we've noticed something really odd happening with a couple of the pick-up goods wagons.

 

Problem:

Initially we thought a couple of the trip pins appear to have "retained magnetism".  

 

What we saw was that when two wagons came close together, just short of being close enough to couple, the trip pins were being attracted towards each other and we eventually tied it down to one particular coupling trip pin which seemed to still be magnetic some minutes after being exposed to the electromagnets.

 

Anyone come across this problem before?  Anyone have any ideas about how to fix it (or at least stop it happening again)?

 

Thanks

 

Elliott

[tender]

Simpler to use smaller neodymium magnets. My first thought when I read NoelG's post was that his magnets sounded a tad on the large side. My experiments to date have been quite successful with 3mm diameter magnets, which fit nicely between Peco code 100 sleepers and are still quite strong enough to do the job.

 

IIRC, somewhere in the Camel Quay layout thread is a video of one-way uncoupling using a single neo magnet adjacent to one rail.

 

That'll be here:

http://www.rmweb.co.uk/community/index.php?/topic/67862-camel-quay-a-north-cornwall-inspired-layout-in-4mm/?p=1264232

and here:

http://www.rmweb.co.uk/community/index.php?/topic/67862-camel-quay-a-north-cornwall-inspired-layout-in-4mm/?p=1265432

[coachmann]

Video demonstrating uncoupling wagons using compact rare earth magnets.  The magnets are a fraction of the size of kadee's own magnets and are easy to install.  They are cylindrical 5mm diameter and 6mm long. A pair are required offset each side of the track centre line.  The magnets need to be almost need to be flush with the sleepers because they are so powerful they would pull the wagons upwards if they were flush with the top of the rail. Cost £2 for 20 magnets = 10 uncoupling points for 20p each.

 

 

https://www.ebay.co.uk/itm/Neodymium-Super-Strong-Magnet-Small-Round-Disc-Rare-Earth-N50-Grade-5mm-x-6mm/272064785631?hash=item3f58532cdf:m:mHD0AMFopaXcU6hNXdPOqZQ

 

They are so powerful one 5mm x 6mm magnet each side was enough and I had to recess them more than I'd expected to avoid the kadee trip pin being pulled downwards towards the magnet causing the other end of the wagon to lift off its axle. One of the things to bear in mind is if the magnets are not carefully placed could cause wagons to jerk (i.e. if the metal wagon axles and trip pins are too close to the magnet surface).

 

NMRA standards advise that typical 2 axle wagons should have a minimum weight of 50-70g which reduces unwanted movements and snatching. Most BR 4mm RTR rolling stock falls way below this weight.

 

https://www.nmra.org/beginner/weight

Where can one buy these compact rare earth magnets?

[Butler Henderson]

Where can one buy these compact rare earth magnets?

Ebay for starters

https://www.ebay.co.uk/sch/i.html?_from=R40&_trksid=p2380057.m570.l1311.R1.TR12.TRC2.A0.H0.Xrare+earth+.TRS0&_nkw=rare+earth+magnets&_sacat=0

[tender]

Where can one buy these compact rare earth magnets?

 

When i was messing about with these magnets i found with the small round ones you need to be spot on stopping over the magnet to get them to work. I used the rectangular bar magnets mounted just under the rail, gives a lot more leeway on where you stop.

 

EP330 - 20mmx6mmx1.5mm

 

https://e-magnetsuk.com/neodymium_magnets/products/rectangular_magnets.aspx

Edited June 17, 2018 by tender

[Butler Henderson]

Sure I read somewhere of using two rare earth magnets either side of the track gives an uncoupling field akin to a kadee magnet

[ejstubbs]

Might you have been thinking of this post of mine earlier in this thread?  No matter if not: there's plenty of info online, easily found by the power of Google, about using neodymium magnets for uncoupling Kadees.  The key point is to make sure that you have a north pole adjacent to one rail, and a south pole adjacent to the other.  That way the magnetic field goes perpendicular to the track, same as it does with the Kadee uncoupling magnets - that's all there is to it.

[coachmann]

Now that I have added quite a bit of extra weight to the plastic RTR wagons AND ordered some rare earth magnets following yesterdays read of this thread, the pesky Kadee magnets worked well this afternoon while filming. However, I intend experimenting with the RE rectangular magnets when they arrive because they will not be as visible... 

https://www.youtube.com/watch?v=lUaGIrJOkA4&feature=youtu.be

[DutyDruid]

Now that I have added quite a bit of extra weight to the plastic RTR wagons AND ordered some rare earth magnets following yesterdays read of this thread, the pesky Kadee magnets worked well this afternoon while filming. However, I intend experimenting with the RE rectangular magnets when they arrive because they will not be as visible... 

 

So, I posted in this forum a couple of days ago about having a problem with what appeared to be residual magnetism in a coupler on stock on Nictun Borrud, asking if anyone had encountered a similar problem.  Having now made time to watch a number of videos in this thread - including Coachmann's - and having spent some time yesterday experimenting I can report the following:

• A pair of coaches and a locomotive always works well when uncoupling at the station.
• Short wheel base wagons always seem to be a nightmare - couplings just won't actuate.
• There is indeed a problem with residual magnetism in short wheel base wagons fitted with Kadee couplers.
• The source of this residual magnetism is actually the weight block in the floor of the wagon.
  • After a lot of faffing around last evening we removed the manufacturer's weights from the floor of a couple of wagons and everything started working as per the book

I probably ought to add that we we aren't using rare earth magnets, we're using "wind your own" electromagnets that are based electrically on the Kadee design but have much smaller surface protrusions between the rails (will post a photo when I get a chance).

 

Also, historically we have tried using rare earth magnets on a test bed with Kadee couplers but gave up because every time the loco uncoupled from the wagon and moved away the wagon would shoot forward and try to recouple.  If you weren't quick off the mark uncoupling just wasn't possible.

 

Now, Coachmann says he is intending to switch from the big Kadee magnets I can see in his video to rare earth magnets but I think he might run up against the same problem that we found on our test bed. 

 

So, the question for the panel is this: Is there anybody following this topic thread that is successfully using rare earth magnets to uncouple short wheel base wagons like the ones seen in Coachmann's video? And if so, what - if any - modifications did you make to the wagons to get it to work?

 

Thanks

 

Elliott

[coachmann]

Rare Earth magnets arrived tis afternoon. First impressions : - They are not just powerful, they are bloomin' powerful and will leap 2½ inches into the air to join another magnet. I look forward to carrying out tests but not right now.

[Pacific231G]

Video demonstrating uncoupling wagons using compact rare earth magnets.  The magnets are a fraction of the size of kadee's own magnets and are easy to install.  They are cylindrical 5mm diameter and 6mm long. A pair are required offset each side of the track centre line.  The magnets need to be almost need to be flush with the sleepers because they are so powerful they would pull the wagons upwards if they were flush with the top of the rail. Cost £2 for 20 magnets = 10 uncoupling points for 20p each.

 

https://www.youtube.com/watch?v=H9aNsxmxYbQ

 

https://www.ebay.co.uk/itm/Neodymium-Super-Strong-Magnet-Small-Round-Disc-Rare-Earth-N50-Grade-5mm-x-6mm/272064785631?hash=item3f58532cdf:m:mHD0AMFopaXcU6hNXdPOqZQ

 

They are so powerful one 5mm x 6mm magnet each side was enough and I had to recess them more than I'd expected to avoid the kadee trip pin being pulled downwards towards the magnet causing the other end of the wagon to lift off its axle. One of the things to bear in mind is if the magnets are not carefully placed could cause wagons to jerk (i.e. if the metal wagon axles and trip pins are too close to the magnet surface).

 

NMRA standards advise that typical 2 axle wagons should have a minimum weight of 50-70g which reduces unwanted movements and snatching. Most BR 4mm RTR rolling stock falls way below this weight.

 

https://www.nmra.org/beginner/weight

I've tried using rare earth magnets with Kadees and mostly four wheel European stock but didn't have much joy with them; the field pattern seemed to be wrong with insufficient force at the centre and too much at the sides but having seen your experiments may experiment again.

 

BTW congratulations on the well shot and edited video.

[tender]

 

 

 

 

So, the question for the panel is this: Is there anybody following this topic thread that is successfully using rare earth magnets to uncouple short wheel base wagons like the ones seen in Coachmann's video? And if so, what - if any - modifications did you make to the wagons to get it to work?

 

Thanks

 

Elliott

 

Simple answer is yes, been using rare earth magnets on our exhibition layout 'Camel Quay' (recently sold on) over a period of four years. (See post 614 and 617) All I can say is they've been 99.9% reliable on both wagons and coaches. The only mod to the wagons (mostly Bachmann) was removing the tension lock and fitting a Kadee 18 (drilled with a 2mm hole in the shank) and fitted to the existing post in the wagon making sure the height was set correctly using the Kadee height gauge. On a couple of wagons a light sponge 'brake' was fitted between the axel and body if the axels were attracted by the magnets. The coaches had NEM pockets fitted with Kadee 18.

 

(the odd 0.1% was mainly due to operator error chatting to onlookers rather than keeping an eye on the job)

Edited June 19, 2018 by tender

[DutyDruid]

Simple answer is yes, been using rare earth magnets on our exhibition layout 'Camel Quay' (recently sold on) over a period of four years. (See post 614 and 617) All I can say is they've been 99.9% reliable on both wagons and coaches. The only mod to the wagons (mostly Bachmann) was removing the tension lock and fitting a Kadee 18 (drilled with a 2mm hole in the shank) and fitted to the existing post in the wagon making sure the height was set correctly using the Kadee height gauge. On a couple of wagons a light sponge 'brake' was fitted between the axel and body if the axels were attracted by the magnets. The coaches had NEM pockets fitted with Kadee 18.

 

(the odd 0.1% was mainly due to operator error chatting to onlookers rather than keeping an eye on the job)

Thanks for that.

 

Bizarrely: On my desk at this very moment a layout data sheet for Camel Quay!  I think I saw you in Sheffield about 15 months ago, you are/were in the queue for an invite to Fareham RailEx so I had better find out who the new owner is!  Could you contact him/her and pass my details on please?

 

Back to the couplings.  I do remember watching CQ operating and being impressed that it did work so smoothly.  If you haven't modified the wagons (i.e. changed the weights) I have no idea why we are having so much trouble with them, unless it is that the shape of the field the electromagnetic coil throws out is such that the weight effectively distorts it too far away from being truly transverse to the rails and so stopping the trip wires from throwing properly.

 

Our "Shed Club" group are meeting this morning and I am going to go down to the Club to mod as many of our SWB wagons as I can to have lead weights rather than iron/steel ones.

[ejstubbs]

Rare Earth magnets arrived tis afternoon. First impressions : - They are not just powerful, they are bloomin' powerful and will leap 2½ inches into the air to join another magnet. I look forward to carrying out tests but not right now.

 

A word of warning: neodymium magnets are also quite brittle, and can shatter or snap as a consequence of being allowed to perform such acrobatic feats.  Small shards of metal in the eye are not pleasant.  (There is normally a note included with mail-order neodymium magnets to this effect, but it doesn't hurt to repeat it.)

 

• There is indeed a problem with residual magnetism in short wheel base wagons fitted with Kadee couplers.
• The source of this residual magnetism is actually the weight block in the floor of the wagon.
  • After a lot of faffing around last evening we removed the manufacturer's weights from the floor of a couple of wagons and everything started working as per the book

I probably ought to add that we we aren't using rare earth magnets, we're using "wind your own" electromagnets that are based electrically on the Kadee design but have much smaller surface protrusions between the rails (will post a photo when I get a chance).

 

This sounds to me like this could be an instance of using magnets that are more powerful than necessary.  It doesn't take much force to uncouple Kadees and given that (as you have realised) ferrous materials which can behave in unwanted ways in the presence of magnetic fields can be found in unexpected places on model railways, it's probably worth ensuring that uncoupling magnets, whether permanent or electrically energised, are only as powerful as they need to be to do the job required.  In the case of your electromagnets, it might be worth experimenting with fewer turns on the coil?

 

My recollection (I don't have any loose to 'play' with just now) is that the on-top-of-the-sleepers Kadee uncoupling magnets aren't particularly powerful.

 

You can use a magnetic compass to get a rough idea of how strong the field created by a particular magnet or set of magnets is, by moving the compass towards the magnet(s)/uncoupling location and observing at what point, and by how much, the needle starts to deflect.  This can also give you an idea of whether or not the magnetic field is oriented in the appropriate direction.  (One of those tiny toy compasses of the kind that sometimes turn up in Christmas crackers might actually be better for this purpose than a full sized navigational compass.)  For Kadees the magnetic field should be perpendicular to the track in the location where uncoupling is required to occur; ideally there should be minimal "leakage" of the field beyond the ends of the of the uncoupling location.

 

I would strongly recommend against using iron filings to try to get a "picture" of the magnetic field.  For one thing, they have a nasty habit of sticking irremovably to permanent magnets (especially neodymiums).  Conversely, if spilt or otherwise let loose on the layout then you have tiny bits of conductive material getting up to who knows what mischief and very likely causing havoc with the electrics, sending the smoke to all sorts of places you don't want it to go...

Edited June 20, 2018 by ejstubbs

[coachmann]

The magnets were like jumping beans attaching themselves everywhere while i was trying to pin them down. Then they didn't work as well as I had hoped seeing as trains have to be stopped precisely with no over-run.

 

Yes I read the label re brittleness, but the pacemaker warning is what done it for me. I will stick with Kadee magnets.

Edited June 20, 2018 by coachmann

[DutyDruid]

This sounds to me like this could be an instance of using magnets that are more powerful than necessary.  It doesn't take much force to uncouple Kadees and given that (as you have realised) ferrous materials which can behave in unwanted ways in the presence of magnetic fields can be found in unexpected places on model railways, it's probably worth ensuring that uncoupling magnets, whether permanent or electrically energised, are only as powerful as they need to be to do the job required.  In the case of your electromagnets, it might be worth experimenting with fewer turns on the coil?

 

OK, I may have put something slightly misleading in my original post by saying that we were using coils of our own making. 

 

So far we've fitted up 4 uncoupling magnets, two of them use solenoids that come from Kadee's own electromagnetic uncoupling kit and the other two are our "roll your own" solenoids which are electrically identical to the Kadee ones.  The only magnetic difference will be that the official ones are wound on some sort of nylon former while ours are built around a styrene tube and sides, but I doubt the magnetic permeability of styrene is sufficiently different from the permeability of the nylon to make any discernible difference. 

 

However, typing this is causing the principles of magnetic theory from A Level physics 44 years ago to swirl around in my mind and I am wondering if you might have a point with the magnets (even Kadee's own coils) being too strong.   Physically, the difference above the baseboard is that instead of using Kadee's massive plates which must be 50mm + long we simply have a pair of 20mm plates sticking up vertically just inboard of the rails (very similar concept to a pair of rare earth magnets between the rails).  What is running through my mind is that in the Kadee "official" unit there is an amount of magnetic flux being pushed through the air gap on 50mm long plates, we are pushing the same amount of flux through a 20mm air gap (a 40% smaller gap).  Higher flux density, stronger (too strong) fields, that might explain some of the things we've seen.

 

I have spent some time during the week dismantling those wagons I can get into easily and replacing their ferrous based weights with lead and it seems to have made some difference but not as much as we had hoped - and I didn't manage to get a photograph of top side of one of our uncouplers before the layout got crated up again (layout out again this weekend).

 

I'll let you all know how the layout and couplings behave early next week.

 

If anyone who is following this will be local to Romsey this weekend do stop by and see us and the layout, Crossfield Hall, Romsey, Sat 1030 - 1700, Sunday 1000 - 1630.

 

Elliott

[melmerby]

Has anybody got hold of the Rapido Kadee uncoupler?

https://rapidotrains.com/on-off-remote-coupler/

 

For those not in the know it is permanent magnets below the track which are rotated electrically through 90^o .

In one position it is inactive in the other it works as an uncoupler. Note it is only powered during rotation so there isn't a constant current drain in the uncouple position.

The housing is tubular and just needs a circular hole beneath the track bed.

 

They were on display at Warley but not for sale. I was told Gaugemaster would be stocking them but when I checked - nothing and Rapido's own site showed OOS.

 

Nowhere seems to stock them in the UK (some say ordered on request)

 

Keith

Edited June 23, 2018 by melmerby

[Butler Henderson]

The magnets were like jumping beans attaching themselves everywhere while i was trying to pin them down.

I fitted them to now long scrapped N gauge layout evo stuck in holes of the appropriate diameter.

[TimP]

Has anybody got hold of the Rapido Kadee uncoupler?

https://rapidotrains.com/on-off-remote-coupler/

 

For those not in the know it is permanent magnets below the track which are rotated electrically through 90^o .

In one position it is inactive in the other it works as an uncoupler. Note it is only powered during rotation so there isn't a constant current drain in the uncouple position.

The housing is tubular and just needs a circular hole beneath the track bed.

 

They were on display at Warley but not for sale. I was told Gaugemaster would be stocking them but when I checked - nothing and Rapido's own site showed OOS.

 

Nowhere seems to stock them in the UK (some say ordered on request)

 

Keith

 

Hi - I got a dozen of them last year but had to order them from the states - I think I got them from Ebay

 

currently building a control panel for them and the associated ground signalling - so haven't actually got around to fitting them yet! I did do a test with one and they are OK I guess not perfect by any means - but a damn site easier to fit and lower power than the Kadee electromagnets

[298]

Has anybody got hold of the Rapido Kadee uncoupler?

https://rapidotrains.com/on-off-remote-coupler/

 

For those not in the know it is permanent magnets below the track which are rotated electrically through 90^o .

In one position it is inactive in the other it works as an uncoupler. Note it is only powered during rotation so there isn't a constant current drain in the uncouple position.

The housing is tubular and just needs a circular hole beneath the track bed.

 

They were on display at Warley but not for sale. I was told Gaugemaster would be stocking them but when I checked - nothing and Rapido's own site showed OOS.

 

Nowhere seems to stock them in the UK (some say ordered on request)

 

Keith

I started a new Inglenook project purely on the strength of having a spare one from a six pack.I

 

I've since rationalized the uncouplers on the original layout after getting past my phobia of fixed magnets and Kadees at HO height on 4mm stock, and now have a spare for a new layout.

 

They can be fitted retrospectively, but are better done when laying the track. Despite using solenoids you don't necessarily need a CDU, but a separate power supply is better to avoid lighted accessories on the same aux circuit dimming when it is thrown.

 

http://www.rmweb.co.uk/community/index.php?/topic/113207-railcrew-uncouplers/

[Sir TophamHatt]

Had my first play around with a Kadee coupler the other day.

They are quite "cute" in the way they couple, and certainly easier to uncouple.

 

But I guess there isn't a list of what kadee types I need to fit what locos?

Or have I got it wrong? Are the types just NEM pockets, or not?

I thought I read there were different height types?

 

I'd be up for converting most/all of my trains but I wouldn't know where to start with the locos/coaching stock I'd want to change.