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Converting To Knuckle Couplers – Worth The Effort?

Pete G who is into OO gauge asks:

“Swapping over to knuckle couplers is a big task so I’ve been told. Are they as good as they are made out to be and should I bother?”

Use the COMMENTS link below to add your answer of make a comment to assist Pete.

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24 Responses to Converting To Knuckle Couplers – Worth The Effort?

  • RogerBsays:

    HI Pete

    I have mainly Hornby, however I have converted some with Kadee No.5 couplers to use at my club.
    There is no twisting to unhook coaches etc. and they look much more realistic.

  • Lawrence Virts, Jrsays:

    I have both of them on my HO layout, the knuckle ones are much closer to the real thing but I have had them in couple also.

  • Stephen Duncansays:

    I think you will find them much better looking and relatively easy to use. I recommend the ones with metal springs. The ones with plastic springs don’t last and will have to be replaced.

  • Don Jenningssays:

    Hey Pete
    There is no other way to go than with knuckle couplers.. They operate properly EVERY single time.
    I would not have anything else but knuckle couplers I am into HO Scale and use Kayde # 5s mainly.
    It may be expensive at first but much more reliable in the long run.
    You do not have to purchase all the couplers right away . You can spread it out over a period of time.== money depending .
    Don J

    • Petersays:

      +1 for adding as you go. I suggest changing one on each of a few wagons/ carriages at first to learn how to do the swap.
      When you are happy with the process then do a loco.
      You will need a coupler height gauge, drills and taps (Kadee does a set of these), files, glues, styrene strip of various thicknesses (to get the right height) etc. Most manufacturers produce centre, underset and overset shanked couplers to assist with getting the height correct. Different shank lengths are also available.
      Kadee sell couplers in sets with draught gear boxes, centering springs and couplers in paper envelopes with 2 sets included (4 of each) or bulk packs of couplers and centering springs which are suitable for US models with the draught gear boxes moulded into the frame.
      Hope this helps somewhat.

    • W Rusty Lanesays:

      I agree completely. Not only do they look more realistic but work much better than horn hook couplers. I have replaced about half of the horn hook couplers with Kaydee #5´s as well and have several cars (rolling stock) with horn hook couplers on one end and Kaydee #5´s on the other end. Until I can come up with the $$ to switch all the cars (rolling stock) to Kaydee´s I´ll continue to use both.

  • Tarasdadsays:

    Nothing beats Kadee couplers for realism and smooth operation. You do have to make sure they are installed and adjusted correctly but Kadee includes excellent instructions on how to do that. They also sell a jig that helps you set them up if needed.

  • Craig Inghamsays:

    Having modeled in both HO & O scale, I have become an absolute believer in automatic operational couplers. I have worked with Kaydee, Weaver and Atlas. Here is my results.
    1. Don’t mix them. While they are touted to be interoperational, I have seen problems.
    2. Weaver couplers do not hold up to heavy use.
    3. In both HO & O scale, Kaydee has severed me best. They have been extremely reliable and durable. The metal ones are better than the plastic couplers.

    I have been a member of several clubs in both scales and they required Kaydee to operate on their railroads. They have learned from experience.

    The change over is not as difficult as some would have you believe. However, the success is in the detail. Positioning, height, mounting and lubrication are essential. That is brief, but should serve as a caution to do the homework before srarting.

    • Billsays:

      How do you adjust for different heights?

      • Sheldon Clarksays:

        Shims, and a standard Height Gauge. I model in British N Gauge and have decided to use Dapol knuckle couplers on some of my wagons – one built from a kit that would have required a method of setting the height of a PECO “ELSIE” coupling box in any case, and another assembled from Dapol unpainted components from which I lost one of the springs. I found removing the original coupling boxes quite straightforward, using a razor saw and a certain amount of care. Setting the height of the replacement NEM coupling boxes, using the Dapol height gauge and the shims provided was fairly easy. Securing the NEM coupling boxes requires the very careful use of the correct adhesive; whilst methyl ethyl ketone (MEK), as in MEK-Pac works with styrene but not with ABS, for instance, so I used EMA Plastic Weld. You need to keep the solvent away from all moving parts & visible surfaces. Having left the weld 24 hours to harden off, I used an NEM-type Rapido coupler to insert the inner coupling box in each case. Once done, the Rapido can be removed & replaced with the knuckle coupler, but the process can be reversed at any time, or other types substituted, such as Fleischmann Piccolo or suitable Kadee. One problem with Dapol couplers, though – it’s easy to lose the centring spring and almost impossible to replace it, even with the replacements supplied by the manufacturer – hence the use of the Rapido to insert the inner coupling box.

  • David Barthsays:

    Simply stated, they are absolutely the only way to go. I’m in HO, but would have no other couplers than Kadee knucklers.

  • Petersays:

    I have a mixture of Kadees and various NEM types including close couplers. So I have a few transitional cars so that I can mix and match rolling stock. The Kadees work very well and are reliable in operation. I do not want to change everything to Kadees as it is a lot of work, and many of my rolling stock items and locos are rare or valuable and I do not want to modify them.

    • Ralph Berrysays:

      I agree Peter
      This is a great way to phase in knuckle couplers, it also helps if you have a collection of classic rolling stock that you don’t want messed with. I have some four wheel vans with different combinations of couplers. The ends are marked on top with a code to show which coupler is where so that they can be shunted onto trains during normal operation sessions.

  • David Stokessays:

    Are knuckle couplers worth the effort? If they are genuine KDs absolutely. Some of the knock offs are plastic or the metal is too weak to take the strain of really heavy train loads (Just like in real life I guess) KDs invented the knuckle coupler and spent many years developing them to the point they are at today; they deserve our support.

    How to use them – firstly they must be set up correctly using the available gauge tool if you don’t have calibrated eyeballs. I seem to have gotten away without one so far. Secondly the magnets in the track for uncoupling need to be wider than those generally available sold for the purpose from hobby outlets. I recommend you read the hobby magazines for fixes and alternatives.

    I have a number of wagons and cars with KDs at each end, and where a rake is unlikely to be broken up, like fixed passenger or mineral trains, a KD on the end of the last, and front of the first vehicle is sufficient saving lots of money. If you aren’t doing a lot of shunting then KDs might not be an expense you need to incur. I love shunting so I use them on most of those troublesome trucks that get left lying around, and pushed around the layout. All my locos are fitted with KDs back and front.

  • Edsays:

    I converted to Kadee #5’s and swear by them. No more pull-a parts in running and easier to uncouple besides they look more realistic then the plastic ones. The company was really helpful for advice when I contacted them for advice. Try a couple and see the benefits. Good Luck.

  • Edsays:

    Oh yes. They have or had numerous types for passenger and higher or lower matching and a neat device to gauge height so they all match when finished.

  • iansays:

    Agree with all the above re Kadees.
    But get the newer #148’s – they are the replacement for the old No 5’s – the 148’s are whisker couplers but they have built in whiskers so you don’t need to use the seperate brass/metal springy thingy that the No5’s have – make them so much easier to put it. AND – get a tube of Kadee Greas’em for lubrication – its a puffer tube of basically powdered graphite – its a must have.
    I’m in New Zealand – I buy in the USA. A 25 pair pack (50 couplers) is US$35 – so around under a pound per wagon!
    Do it – you’ll never look back!!!! Cheers.

  • Davesays:

    I would recommend switching to Kadee brand knuckle couplers or a metal brand. Stay away from plastic knuckle couplers as they give out in time. I run HO scale and not only did I switch over to knuckle couplers “kadee” but I correctly weighed the cars to standard NHRA I believe. I also added metal wheels. The biggest problem I faced was getting each coupler to the correct height. I used thin cardboard shims(plastic works too), or the fiber washers to raise the car up above the trucks slightly. It is a process but the results are well worth it. I used to run 100 car ore trains at the club. Back them into yards through switches, mainline, whatever. Other members become impressed when “your equipment” runs smoothly. I was even approached once by the president of our club to help get a new members cars up to spec. Good luck and any questions I’d be glad to help.

  • Briansays:

    Yes, in my experience in HO there great but if switching to use the features intended they have to be Kadee’s there the only ones I found to last and work properly and when the magnetic trip pin is adjusted to the correct height with the Kadee coupler gauge and pliers especially when using the Kadee inserted between the track or under the track magnets for uncoupling, Also adjust trip pin properly so it doesn’t hook on turnouts. When going very slow put the train in reverse then forward again to release the coupler tension on the couplers and the couplers open right up and the cars are unhooked over the magnet, pull forward and off you go without the cars, back up again till they reconnect off the magnet pull forward and your reconnected and as long as there’s tension on the couplers you can drive right over the magnet and they’ll stay connected. Other brands even with springs I never got to work properly even the plastic ones with metal springs and trip pins, I use them for cars I don’t need to unhook over the magnets. Stay away from the cheap ones with little plastic tabs instead of springs, they get bent out easy and stay that way and your cars unhook, there junk. Cosmetically to me they look much better than horn and hook also, the trip pins on the couplers are supposed to look like hoses hanging, buy in bulk for the better deal and if you can I suggest the one piece ones with whiskers attached for the draft box spring though usually more expensive verses the ones with the separate gold square type draft box spring, easier to install them to me. One last thing to be aware of when ordering the come in many verities, regular, medium, short and long shank also in these sizes is center or over and under shank couplers to make up for irregular car or engine heights. There’s more sizes and adapters to replace just about any couplers, I think I better stop chattering on, hope this helps your decision but if done right with knowing all the options the more you can do and it makes the hobby more enjoyable without problems and not blaming it on the cat lol.

  • Peter Glensays:

    Hi take a look at Rapido Trains and seek out rail crew uncouplers.You can also buy a decoupler that you can slide down between the cars and the magnets attached will uncouple the Kadee couplers.Rapido trains are in Canada (I think)

  • Jeffsays:

    Bottom line, if you intend to couple and uncouple cars, dropping them in sidings, then knuckle couplers are indispensable, and Kadee whisker couplers are trustworthy and easier to install than the old stalwart #5’s. If you just want to run trains around and around, like passenger trains, then it’s not necessary. Bachmann has recently begun selling couplers with coil springs, and I installed some, but time will tell how long they’ll last. Do not get the older non-spring Bachmann couplers under any circumstances; far too fragile and once that skinny metal leaf bends, that’s the end it.

  • Peter Dsays:

    I have to agree, Kadee’s are the best knuckles. One thing not mentioned here, if your track is uneven then knuckles could pose a problem. they can slip up and over one another if there is a height difference, for example at a board join. Our club modular system specifies Kadees and at shows they are by far the best for us, much less “Hand of God” than other systems. They do need regular tuning however, the journey to and from a show can be enough to knock a knuckle out of line. If you run fixed rakes then just put knuckles at the ends and on loco’s and use the shortest fixed coupling your curves will allow. One other down side of knuckles is, they often do not like coupling on curves, so all shunting operations need to be on straight track.

  • brian harpersays:

    I am in the process of changing to KADEE and useing #242 gear box for the coupling, if you the newer HORNBY coaches check the coupling as the newer ones have NEM slots which makes it easier to fit the KADEE nem coupling, a problem may be the height if useing HO loco’s like I have,
    Just to check which type of head on knuckle head you will need.

  • Frank Kopkesays:

    I have had a shunting layout for some years and therefore need many incidences of coupling/uncoupling.
    While the Kadee type knuckle couplers (and there are many brands now available at VASTLY different prices) are excellent and work reliably and well, they do require regular and on going maintenance. This can become a burden with larger inventory of wagons…
    The solution I have dome to with OO gauge equipment usually of British origin, is to modify (only slightly) the standard hornby/bachmann style couplings based on the videos below.
    Hope this helps to save money and work for you.
    Best of luck and continue having fun.

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