How to Build a Simple Model Train Kit

  • 01 of 06

    Model Train Kits - Getting Started

    kit parts
    This simple Accurail covered hopper kit is a good place to get started, or a relaxing and quick project for the more experienced builders. ©2011 Ryan C Kunkle, licensed to, Inc.

    It wasn't long ago that nearly every model on a layout was either built entirely from scratch or from a kit. Ready-to-run models were associated with inexpensive train sets and toys. Many good models were available as kits that could be purchased inexpensively and assembled quickly. More advanced "craftsman" type kits were and are also available.

    While kits of all difficulty levels can still be found, the era of the "shake-the-box" kit has largely come to an end. This is in many ways unfortunate as those simple kits were a great way to gain early modeling experience and to build larger rosters of rolling stock without breaking the bank. There are a few manufacturers who still market their equipment as inexpensive kits.

    The HO scale kit for this tutorial is made by Accurail; model No. 2051. Accurail calls this the “ACFX Blue” car – it is an ACF Centerflow covered hopper leased to the Tenneco Corporation. It is one of over 100 paint schemes offered for this model for a list price of $14.95. Many of their other kits are even less expensive.

    Unpack the model and familiarize yourself with the kit components. Once you know what to do, basic assembly of this model takes only a few minutes.

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  • 02 of 06

    Model Train Kits - Assembly Basics

    Glue kit parts sparingly and from the inside. ©2011 Ryan C Kunkle, licensed to, Inc.

    Following the diagram that comes with the kit, begin removing parts from the sprues and adding them to the shell. Don't simply break the parts off of the sprue. Use a pair of sprue nippers and a hobby knife as shown in this basic kit assembly primer.

    All of the parts are a tight fit and gluing may not even be necessary. Do not force parts into place. If the parts do not slide together, scrape a little paint off of the pieces or from inside the hole with a knife or file. Too much pressure can snap the mounting pins. If you need to glue parts, apply the glue from the back or inside of the shell.

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  • 03 of 06

    Model Train Kit - Orientaion and Assembly

    end details
    End view shows the proper orientation of most of the kit's parts. ©2011 Ryan C Kunkle, licensed to, Inc.

    When assembling this or any kit, pay close attention to the proper arrangement and orientation of the parts. Accurail has made this much easier on this kit by keying many of the parts so that they can only be inserted in one place and one way. The exploded diagram with the instructions also shows the right way to put everything together.

    Insert the air brake cylinder and reservoir in the one end sheet. Insert the triple valve and three hopper doors in the floor. Note that the doors have different size pins to help get everything arranged properly. Insert the handbrake wheel and roof hatches in the car body. Note the proper arrangement of the hatches. When looking at the brake wheel end of the car, the hatch hinges should be on the right.

    Once all of the small parts are in place, insert the two ends into the car body. All of the brake components go on the same end of the car as seen here.

    With the car on its roof, insert the weight into the tabs on the car ends. Install the floor after completing the couplers and trucks as shown next.

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  • 04 of 06

    Model Train Kit - Trucks and Couplers

    A Kadee No. 58 coupler and spring are an easy substitute for the kit's couplers. ©2011 Ryan C Kunkle, licensed to, Inc.

    Installing the trucks and couplers is next. These are among the most critical components of the kit if it is going to operate properly.


    Accurail's kit includes their Accumate® knuckle couplers. These work well and are compatible with other knuckle couplers, but for a universal operation, I replaced the couplers on my kit with Kadee No. 58 scale couplers. These will fit in the Accurail box without any modification.

    Place the brass centering spring in the box first, followed by the coupler. Remember that you are working upside down, so the coupler actuating lever must be up. Clean any flash from the coupler box cover and screw it in place.

    When securing the cover, take care to get a tight fit without over-tightening and stripping the screw. The coupler should swing from side-to-side freely without binding and with no vertical play.


    Note: If you are going to paint and weather the trucks, it is easier to do this before assembly. For the sake of simplicity of instruction, we'll proceed with assembly now. Of course, you can always remove the trucks later if you decide to weather.

    The trucks are installed next. Accurail's kit includes plastic wheels. These look and roll fine, but I chose to substitute metal wheelsets. The proper wheels for this car are 36" diameter. Several manufacturers make these, I used some from Walthers Proto 2000. Metal wheels provide better stability and are more resistant to dirt build-up.

    Simply spread the truck side frames slightly and insert the wheels.

    Screw the completed trucks onto the car body. Proper pressure here is important. Both trucks need to swivel freely. For the best ride, a three-point suspension is needed. Screw one truck tight enough that it can swivel freely from side-to-side with no rocking play. Screw the second truck just a little bit less tightly, allowing it to rock side-to-side slightly. This combination will keep the car from rocking as it travels down a rough track.

    With the trucks and couplers installed, attach the floor to the car body with the triple valve on the brake wheel end of the car.

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  • 05 of 06

    Model Train Kits - Extra Parts

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    Hang onto the extra parts from the kits for scenic details or future projects. ©2011 Ryan C Kunkle, licensed to, Inc.

    You may notice you have some extra parts left over. The original kit wheels and couplers, along with other parts still on the sprue including some non-operating couplers and pins. The pins are left over parts from an earlier version of these kits that used the pins in place of screws to attach the trucks. The couplers can be used for more detailed display models.

    Even though you won't need the parts on this car, don't just toss them in the trash. Most modelers keep a spare parts box, or boxes, full of extras like these. A small parts box of clear plastic bins can be found in hardware or craft stores.

    The couplers and wheels can be used to detail a shop scene or painted a rust color and thrown in a scrap load for a gondola. Those pins might come in handy if you have an older version of the kit and need a replacement, or they could be modified and used as roof vents or other details. Some modelers even keep the sprues themselves and use the plastic to build rain spouts, piping or other details.

    Continue to 6 of 6 below.
  • 06 of 06

    Model Train Kit - Checking the Gauge

    A Kadee coupler gauge and NMRA standard gauge confirm that the couplers and wheels are all in gauge. ©2011 Ryan C Kunkle, licensed to, Inc.

    The kit is now assembled, but we have one more important step before putting the new car in service. Check the wheels, couplers, and weight to ensure everything will work perfectly.


    Use an NMRA Gauge to check the wheels. All of the wheels on this car were right on spec. If something is found out of gauge, gently push or pull on the two wheels while twisting them in opposite directions on the axle and recheck.


    Check both couplers with a Kadee coupler height gauge. Check the proper height and alignment of both the coupler and the actuating wand. Both couplers hit the gauge exactly on this car.


    This car comes adequately weighted as designed. You can check the weight using a small postage scale. If necessary, you could easily add more weight to a kit like this during assembly. Keep any additional weight as low as possible.

    Beyond the Basics

    That's it! Your kit is finished and ready to go to work on your railroad. If you do nothing else, you will have a good looking and smooth running freight car. Of course, if you'd like to go a little farther, there are lots of ways to customize this model.

    Weathering this car to make it look like it has a few years of service behind it would be the most obvious step. You could also add additional details, or build a few more and change the road numbers. If you opt for this step, Accurail actually makes decal sheets designed specifically for the car you've purchased that make this step even easier.

    However, you decide to customize your model, enjoy it and make it your own. Now that you've finished your first kit, you'll be amazed how quickly the next one goes together.