The Hobo's Guide to Kadee Couplers

Kadee is a company that produces a long line of train products and their couplers have long been the gold standard of model railroading. By standardizing the couplers across all your trains, you're ensuring that you can run your cars together in any order without the need of a conversion car. While any brand of coupler can be used to standardize your fleet (everyone has their favorite), Kadee offers a number of advantages that aren't always seen with other brands. While Kadee makes couplers for both HO and G scale, this article is geared towards G scale conversions.

Advantages

First and foremost, Kadees are strong. It's very rare for a Kadee coupler to break, and they certainly seem to hold up better than most when running very long trains.

Another advantage of Kadees is the smooth coupling they offer that doesn't require a locking or clicking mechanism to couple or decouple. A number of brands require cars to be pressed together with a good amount of force for them to lock together and then require the pressing of a pin to unlock them. Kadee couplers just slide together and can be uncoupled with a magnet or just gently picking up the car. This makes operating your trains and switching cars much more enjoyable.

Disadvantages

Kadees can be expensive (roughly $7 per pair), and can come uncoupled on accident if you have very uneven trackwork. If you're just starting out and feel like Kadee's are right for you, it's highly recommended to convert as you collect so you don't have to bite the cost of converting 20 or more cars at a time.

Body Mount vs. Truck Mount

Before diving into the technical details of converting cars and engines to Kadees, we first need to establish if body-mount or truck-mounted couplers will be best for your railroad.

Truck mounted couplers are easiest to install and are best for smaller diameter curves (less than 8'). Installing truck-mounted couplers generally involves simply unscrewing the original coupler from the truck and attaching the Kadee in it's place with very little shimming required.

Body-mounted couplers are more realistic (prototypical), but generally require at least 8' diameter curves (10'+ is recommended). They're also more difficult to install, as a platform/base must be built on the bottom of the car to attach the gear box to. A huge advantage of having body-mounted couplers is that the stress of the train is focused through the body of the car and not the truck, so longer trains can be run without derailing on curves.

The cost differences between body and truck mounted couplers are negligible, so price shouldn't really be a factor when deciding between truck-mount or body-mount couplers.

Picking the Right Coupler

At a first glace, the number of different types of couplers that Kadee has to offer can be intimidating. Kadee makes two different styles of couplers: #1 Scale and G Scale. #1 Scale is strictly 1/32 scale and are therefore smaller than most G scale available on the market since most equipment seems to come in 1/24 and 1/29 scale. As such, the G scale couplers are more popular than the #1 Scale couplers. There are two versions of each style of coupler: Original and "New Generation Type E". Both versions are functionally the same and 100% compatible with each other, but the "New Generation" couplers are the latest design iteration and offer a number of improvements over the origianl version, namely the coupler spring is now internal to the assembly instead of external which goes a long way in reducing rust and extending the life of your coupler.

Once you've decided on the style and version you want, you just need to buy the corresponding coupler for the type of equipment you're wanting to convert. Fortunately, Kadee has done all the dirty work for you and has compiled a list of the different manufacturers, their products, and which coupler goes to which piece of equipment:

Large Scale Conversion Chart

From the link above, just click on the manufacturer and find the product, then look to the right and find the corresponding coupler # based on the style/version you picked earlier.

You'll notice that it's primarily the locomotives that have unique couplers. 98% of all G scale rolling stock will utilize the same coupler, and these couplers are sumarized in the table below, broken down by the style and version discussed above:

Installing Couplers

Before buying your first package of couplers, consider investing in a Kadee Height Gauge. This gauge sits on the track and can be used to make sure that all your couplers end up being the same height, allowing you to add or remove shims as necessary during installation. The Height Gauge isn't optional if you're wanting all your cars to end up with uniform coupler heights - it will pay itself off very quickly. In addition to the height gauge, you'll need to pick up one pair of body-mounted couplers of your style to attach to the height gauge. The height of your couplers should all be the same regardless of whether or not you're using truck or body-mounted couplers, so this height gauge can be used for both types of installations.

The actual installation processes are many and will vary depending on the type of equipment you have. Drilling into the Large Scale Conversion Chart will show installation instructions for many types of couplers (click on the equipment name), and there is a dedicated Facebook group called Kadee Couplers G Scale Setups that you are more than welcome to join to ask questions about your particular installation. Trying to get into each type of installation is beyond the scope of this article, but the overall process of attaching couplers to rolling stock is listed below:

For truck-mounted couplers, the process is as simple as removing the screw holding the existing coupler in place and then installing the Kadee in it's place. You will usually have to use a small drill bit to drill a new hole on the truck arm to line up with the screw hole on the Kadee gear box. Additionally, it may be necessary to sand down the inward-facing end of the gear box to prevent it from rubbing against the outer axle of the truck.

Body-mounted installations get a little more advanced, but they're pretty generic as well. First, remove the existing coupler and turn the truck around such that the coupler arm is facing inward. Then a base needs to be constructed on the bottom of the car for the coupler to attach to, ensuring that the height lines up with the Kadee Height Gauge.

A Note on Conversion Cars

This article previously mentioned conversion cars. These are cars with two different style of couplers. For instance, if half your cars are Aristocraft and half a Kadee, it would be a good idea to have one car that is half Aristocraft and half Kadee to be able to build longer trains using cars from both pools of couplers. This is especially advantageous for people with many cars to convert and don't have either the time or money required to convert them all at once.