This week’s post will be a continuation of my step-by-step build of an N Scale A-B-A ready-to-run set of Alco C-855 locomotives, and will be concentrating on reassembling the trucks and pilots now they’ve been painted.  You can find part one of the build here.

In last week’s post I stripped down the trucks and pilots ready for painting and below you can see all 12 trucks now in shiny silver. They’ve been sprayed with Humbrol enamel paint.

To reassemble I start with one of the inner trucks.  These are not powered and simply  track along behind, or in front, of the lead truck forming the span bolster.  A ‘span bolster’ is the name given to this configuration of trucks.  On the prototype they’re linked together by a beam which is connected to the locomotive at one rotation point, allowing the truck to articulate. Together, the trucks form one big truck under each end of the locomotive.  Having the trucks individually fixed to the locomotive would make it harder to negotiate corners.

The wheels have points on the end of the axels and simply press into the truck which has holes for the points.  You’ll need to pry the sides apart slightly to allow the points to drop down into the molded holes.  If the wheels don’t spin freely they’re not in the right place.

The powered truck fits over the peg on the trailing truck.

The metal weight is then fitted over the wheels.  Once fixed in place this will also stop the trucks from separating.  The metal weight is important as it stops the unpowered truck from jumping the track and derailing the locomotive.

The weight is held in place by one screw on the underside.

This can then be repeated for each set of trucks, six in total for the A-B-A set.

The pilots are painted in UP Harbor Mist Gray.  I used Tru-Color paints for this.

The front of the chassis is slightly easier than the rear as there’s less to reassemble.  The truck center is as we left it with the black coupling pocket positioned between the metal halves, holding them in the right place.

This particular chassis is for the C-855B and I’ll be using Uni-Mate couplers between the A-B-A set.  These give a great coupling which can’t be uncoupled without lifting the locomotive.  The Uni-Mate fits into the pocket with a spring as shown below.  This is the same fitting as the original Rapido coupling, and a Micro-Trains knuckle can also be fitted in the same way, which I’ll be using on the two A units.

The front pilot can then be fitted over the truck which also holds the coupling in place.  It will click in as the pegs find their positions.

The rear of the chassis is similar but the pilot fixes on from above the truck (behind in this example as the chassis is upside-down).

By squeezing the metal halves slightly together the pilot will fit over and the two locating pegs should clip into place.

The coupler pocket can then be pushed in-between the halves acting as a wedge, clamping the pilot in place.

Again I have fitted a Uni-Mate coupler as this is the C-855B.

To stop the coupler falling out the U-shaped plastic clip fits over the pocket holding it all in place.  The geared wheels can then be replaced.  If, as below, your model had the brass wheels wipers, don’t forget to put them back in, ensuring the wipers are behind the wheels.

The trucks can now be fixed back onto the chassis and held on using two screws in each end.

With all three chassis reassembled with their new silver trucks my attentions can now be turned to painting the shells, which is a time-consuming project and I’ll be covering that in another post soon, but just as teaser here’s one under way.

One thing I will say, having painted this shell we’ve really seen a difference in the quality of the 3D printing, not only in the improved detailing in the model but also the paint adheres really well. The flat surfaces are very smooth, and all together this makes for a great model. It’s rewarding to see the developments that have taken place in 3D printing, especially when we can pass those benefits onto you.