Converting Rapido to NEM Couplings

I've been getting a few N guage questions recently, and top of the list is "how do I convert Rapido couplings to NEM?" Now, many readers might not even know what Rapido or NEM couplings are, let alone why you'd want to change from one to the other.

So, this article should help to answer a few of the more pertinent N scale coupling questions, as well as address the theme of changing from one type to the other, along with some helpful resources.

The key difference between NEM and non-NEM couplings is that NEM provides for a pocket that can be used to change the couplings - in other words, if you have rolling stock that is compliant with the NEM standards, you are free to change the couplings for those that are also NEM compliant.

That includes Kadee (now Micro-Trains), Dapol, Graham Farish, and Bachmann, amongst others.

Non-NEM couplings are usually moulded to the rolling stock, and as such cannot be changed - Rapido couplings fall into this category.

A Quick Note on Standards

Here in Europe, we have a body that was set up to standardise many aspects of railway modelling, from track widths to coupling heights, wheel sizes and bogie placement. The only downside is that most of the documents are only available in French or German.

Officially called MOROP, the list of standards is impressive, across the gauges. The set of standards that deals with N scale coupling pockets  is called NEM 355. While this document is in German, a Danish web site has provided a great overview of the pertinent points of the N scale NEM standards.

For those who want a bit of a potted history of couplings, from Rapido, to NEM and including standard knuckle as well as automatic and magnetic variations, it can be found on the N Scale Division web site.

Rapido Couplings & Moulded Couplings

Rapido couplings had been the standard for many years, despite not looking especially good, and not really allowing for the close-coupling that modellers demanded. They worked, and were also avaiabile across a wide variety of rolling stock, having been licensed to manufacturers, which boosted their penetration.

Otehr manufacturers (especially in Europe) used proprietaty moulded couplings, and to this day, if you buy Peco or Dapol rolling stock kits, it is common to find that they have moulded proprietary couplings; and older ready to run models also have this restriction.

Subsequently, many people have found it desirable to convert their Rapido and propriertary moulded couplings to NEM pockets to allow them to use more modern couplings such as magnetic couplings from companies like Micro-Trains.

Converting Rapido to NEM Couplings

To do this, you are going to have to use a knife to remove the old couplings, and then obtain a NEM kit to replace the old moulded coupling in its entirety. Some advice : practice on a wagon that has little value to you, as the first time that you do this, it may well go very wrong!

On the Model Rail Forum, there is a guide to replacing couplings with NEM pockets, complete with pictures, done far better than I could, and is well worth a look.

The key points to remember are that:

• you need to remove the old coupling carefully
• the new pocket needs to be at the right height
• the couplings also need to be NEM compliant

To help get these right, there are a couploe fo useful products on the market.

Buyer's Guide to NEM Pockets & Couplings

Dapol make both a pack of 20 pockets, as well as a smaller kit. The smaller kit contains 5 pockets, but also a tool to help you get the height just right. Called the NSPARE9 kit, I would recommend it for anyone converting to NEM.

As for couplings, despite being a fan of Kadee magnetic auto-couplings for HO/OO gauge, I actually prefer these Graham Farish couplings for N scale. For those who want to see a general overview of available products, the Gaugemaster web site has a great variety.

Hopefully with this information in hand, converting your old couplings to the NEM standard should be a less daunting prospect!