Peter's Model Railroading | The Equipment | Box Cars | SP A-50-6
Construction: Couplers & Wheels

The underframe of the kit does not come with pre-defined holes for the coupler box, so you are free to install whichever coupler you want to use. I have standardized on the Walthers HO-scale Proto MAX coupler. The problem with pre-drilled holes is that the two outside tabs on that coupler don't match the typical S-scale Kadee coupler's outside tabs, and so I usually wind up only putting the center screw in the model. This, of course, can lead to the coupler rotating, so I counteract that with some superglue on the back. By not having pre-drilled holes, I can use the two outer tabs to install the screws I want to use for this coupler. To drill the holes exactly where I want them, I put a center mark on both the coupler box lid and the underframe. I stuck some double-sided tape to the coupler box lid, and carefully positioned it where it needs to be. I could then pre-drill the holes, as is shown in the photo.

I then removed the tape and built the coupler, and installed the two screws. I did tap the holes first, as that makes installing the screws go a bit easier. Note that the magnetic-uncoupling hook on the couplers will be cut off at some point as I don't use that method of uncoupling.

The trucks are easier to install. There is a dimple in the underframe for where the hole should be drilled. I drilled that (make sure to keep the drill as perpendicular to the underframe as possible), and used a tap to put the spiral grooves in the hole. There is a lot of material to drill through here, which is a good thing, but it will take a bit of time to do so. I am using a pair of MTH trucks I have left over, which are not the correct style of trucks to use, but they will have to do until I can get a pair that is correct. Wiseman Model Services has a kit of the correct type of truck, but the car's kit instructions state that Pre-Size may produce their own.

(external link: Wiseman Truck)

Update: Almost exactly two years later, I am finally getting around to building the trucks that are appropriate for this car. At the time that the Pre-Size car kit came out, the trucks weren't ready yet. Pre-Size commissioned Miniatures from the North to produce these 3D-printed trucks for them. They are the T-section Bettendorf trucks.

(external link: Pre-Size Model Specialties)

These are all of the parts that come in the package (which makes for two trucks). The wheels are Miniatures from the North's own design. The bolsters and sideframes are pre-colored 3D-printed parts. The transparent sprue holds the nylon bearings. The final part is the collection of 8 springs.

This photo shows how to insert the bolster into the sideframe. First, make sure that you get both of their orientations correct. The flatter part of the bolster sits at the top of the truck (where it touches the body). The sideframes' orientation can be determined by the oiling reservoir covers, which should be aimed down. Insert the bolster at about a 45-degree angle until its side "lips" fall in line with the interior of the sideframe hole. You can then carefully twist it into its normal horizontal position.

Then repeat this with the other sideframe.

You can twist the nylon bearings from the sprue and then place them into the cup of the sideframes. While I show them installed here on both ends, it is my recommendation that you only insert the two needed for the first axle that you are going to install. This is because these nylon bearings fall out of the cups quite easily and they can then roll away. When you have the first axle installed, then install the other nylon bearings for the second axle.

The trick to installing the axles into the nylon bearings in the sideframes, is to slightly twist one sideframe up and one down, with respect to the bolster (as if one side of the truck is going over a tall speed bump). You can then relatively easily insert the axles. Make sure to keep the sideframes perpendicular to the bolster, otherwise the parts may break (as stated in the instructions).

The final step of inserting the 8 springs proved to be the most difficult part of this assembly project. If you look closely, at the bottom of the bolster part there is a small nub. I start off by putting the spring on that nub. I then used my fingernail, a small pair of tweezers, and/or a toothpick (whatever it took) to carefully guide the bottom end of the spring into its position on the bottom plank of the sideframe. That plank has a very slight indentation that perfectly fits the spring. When you get the spring to slide into it, you will notice it "clicking" into place. That's when you know it is properly installed. For nearly all of these springs it took me several tries, so patience and a steady hand are required. Also, be prepared for the spring taking off on you; there are no spares in the package!

This is what it should look like when both springs are installed on both sides. I did the two springs on one sideframe first, before doing the other sideframe. That is because if there is only one spring installed, the bolster can rotate on you and the whole thing falls apart again.

And, here are the two trucks, ready for installation on the car.

Installation was trivial, as I removed the previous stand-in trucks I had installed and put these in their stead. The wheels roll freely and it all looks very nice.