If you're referring to Northeast Narrow Gauge in Wiscasset, Maine, I have built several of their 1:20.3 kits and have been very pleased with them.
The only one I didn't like is the 13 Ton Class B Dunkirk. The kit itself is not bad, but the drive system is horrible. I have shied away from any more of their locomotive kits in the belief that they may all use the same system as the Dunkirk.
Even worse, the Dunkirk uses brass rod drive shafts from the gearbox to the trucks, and 90-degree twisted O-rings between the drive shafts and truck axles. It makes a horrible, high pitched whining sound but barely moves, and the O-rings break or burn from the friction within days, depending on how much you run it.
I just gave up after the first week and put it onto a shelf as a display curiosity.
Have fun with your trains
The rolling stock kits I have built are mostly wood with metal castings, metal straps, or metal rods for the detail parts such as brake rigging, grabirons, etc. Some, such as their tank car, kit #248, included a piece of PCV pipe for the tank with a cardboard wrapper.
Note that most of their kits do not include the trucks. The trucks they sell are metal. One additional thing I always do is drill out the journals and insert ball bearing races that I order from Great Big Trains (http://www.gbtrain.com) or purchase from an Ace Hardware store in Tucson, Arizona. I put these races in all of my rolling stock, whether scratch built or store bought, and they double the length of trains I can run.
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