Trucks and Wheel Sets in N scale


Micro-Trains diagrams on trucks with couplers.

From the Micro-Trains Instruction Sheet:

For your convenience, we have included two styles of bolster pins. The #16000 type comes with a bushing and washer. The #1034 Atlas compatible type has a larger diameter.

Install Micro-Trains Magne-Matic trucks using original or supplied bolster pins. Trucks should wobble slightly, so DO NOT push pins in too tightly. Make sure bulge part of kingpin hole is towards center of car, to give added clearance for coupler draft gear box.

For installations on CON-COR Sekisui cars with larger king pin holes in underframe casting, using bushing with small diameter hole (provided with Micro-Trains trucks): Carefully press small step of bushing into top side of large hole in underframe as tight as it will go. If bushing sticks out past underframe, either top or bottom, trim off flush. Use spacer washer (included) between truck bolster and car bolster.

For Bachmann cars using a bolster screw: Enlarge truck bolster kingpin hole with a 9/64in (3.6mm) dia. drill. After trucks are installed, using original screws, follow testing instructions below, to assure proper operation.

Body Mounting Micro-Trains Magne-Matic Couplers. Use Micro-Trains #1054 Adjustable Micrometer Height Gauge and Coupler Conversion Guide to determine which coupler most closely matches the car's coupler mounting platform to the mounting height of coupler chosen by shimming or removing material from either coupler/mounting platform or truck/body bolster.

Before installation, check coupler for proper centering action. Couplers should move freely from side to side, in and out, always returning to center position. If it doesn't, add a puff of Micro-Trains #231 Greas-em, and workcoupler back and forth to burnish parts. DO NOT USE OIL.


After couplers are installed, follow testing instructions below to assure proper operations.


  1. Place car on track, and check coupler height using Micro-Trains #1055 Coupler Height Gauge (Fig. 2). If coupler is too low or high, adjust by shimming or removing material from either coupler/mounting platform or truck/body bolster.
  2. Check trip pin height with Micro-Trains #1056 Trip Pin Height Gauge. Lay gauge across rails and roll trip pin up to it (Fig. 2). Pin should just clear gauge, but not be so low it fouls on turnouts and crossover rails. If trip pin is too short or long, adjust by pulling or pushing up or down in coupler shank.
  3. If couplers cross the wrong way over uncoupler, locking closed instead of open, adjust trip pin angle. Trip pin should line up with knuckle part of coupler (Fig. 1). Remove pin by carefully pulling straight down while holding coupler knuckle. Twist Pin top so it angles outward slightly more then reinstall. DO NOT twist trip pin while it is still installed in coupler.

Wheel sets

Link to a photograph of 33" car wheel sets in N scale: Micro-Trains, Micro-Trains low-profile, Atlas, NWSL, Fox Valley Models, Atlas metal, Intermountain metal.

From the Micro-Trains Instruction Sheet:

Replacement N Scale Wheel Sets (Ready to install). Fits: Aurora and Minitrix. Use as a replacement for Micro-Trains standard profile wheel sets. For all others, it is recommended to replace existing trucks with Micro-Trains Magne-Matic Trucks.


Remove trucks from underbody to make it easier to hold on to them and to avoid damaging side frames. Hold truck with thumb and forefinger of one hand, place thumb of other hand on opposite side frame. Using index fingenail, gently spread truck side frame just enough to clear axle cone of wheel set, allowing it to drop free. Do one end at a time. As you remove one original wheel set, replace it with a new Micro-Trains wheel set, to lessen the chance of causing damage to side frame. Reinstall trucks to car underbody.

Fig. 1

TESTING: Place on track near magnetic uncoupler. If car is drawn into magnet, add one or more restraining springs to axles (one per axle), to create additional drag. (Springs are available separately from Micro-Trains in package #1953). To install, remove wheel set as it is explained above. Place spring on axle cone (Fig. 1). A dab of saliva from your tongue will help hold spring in position while pushing axle and spring back into truck side frame.

Fig. 2

To keep wheel sets properly gauged and to test couplers, use Micro-Trains #1055 Height Gauge. This terrific tool does six jobs 1) wheel width gauge, 2) uncoupler gluing jig (hold uncoupler in place), 3) track width gauge, 4) car underframe (coupler mounting platform) height gauge, 5) coupler height gauge, and 6) trip pin height gauge (#1056 is included in the #1055 package).

Updated 2009-01-04