PIKO 2 Bay Hopper Car Experiences & Body Mount Couplers


Ted Doskaris

January 17, 2024

Rev GE-A Initial Release


Shown above is an example PIKO hopper model representative of an older era prototype car that could have been upgraded in more modern times with "roller bearing" trucks relegated to ballast or sand track maintenance service.


About the PIKO Car & CamPac Boxes

Mounting CamPac Box

PIKO & Aristo-Craft Car Comparison

Upgrading PIKO Car to "Modern" Era

Adding Pneumatic Brake Parts

PIKO Car Weight Configurations




About the PIKO Car & CamPac Boxes

PIKO, including antecedent brand names MDC/Roundhouse/Mainline America (henceforth, collectively referred to as PIKO) have / had various versions of this 1/32 scale car that include open top types of rib side, “offset” side, and the car with a removable top cover.

First impressions of the 2 bay hopper car is that it’s feather light (weighs 1 pound).


The Car also has a noticeably flexible fitting underside chassis frame lacking any fastening hardware.


The frame can be removed & reinstalled by bending its spine, as its ends butt fit into and are retained by the car body's draft gear openings (slots).


As to prototype, the PIKO external ribbed version model closely resembles the United States Railway Administration (USRA) 1917-1920 World War I era car having 7 external side ribs and brake lever rather than a brake wheel.

(Later years of this USRA car had a brake wheel mounted atop of a vertically mounted shaft.)

In a 1/29 scale environment, the car could represent a 30 foot long prototype coal car. The car does include reasonably good detail (including the molded-in brake lever). The Car is factory equipped with plastic trucks having plastic wheels and hook & loop couplers.

The end sills of the car having a slot for retaining the under frame resembles where a prototype body mount coupler “draft gear” could be located.


The slot, which provides some exterior recess with under frame installed, is used to advantage to body mount the "keyed" 3-D printed CamPac coupler box.

Accordingly, to both improve the car’s appearance and operation in a long heavy train, body mount CamPac BoxesTM fitted with Kadee centerset (no offset) “G” scale AAR E type couplers from the 907 kit can be employed.

To improve the Car's operational stability in a train on curves (8 foot minimum diameter), Replacing the trucks’ plastic wheels with heaver USA Trains metal wheels is done.


As to the car's enhanced stability, this is demonstrated in the below illustration where the car is able to "self center" upright just from the added weight of metal wheels! (The Car with metal wheels and body mounted CamPac coupler boxes fitted with Kadee centersets was tested without problems on my under house layout as the first car behind the locos pulling a heavy 27 car freight train around many loops.)

For proper coupler alignment with Kadee coupler height gage, spacer washers are to be placed over the chassis bolster pivot post before trucks are mounted.

For a typical 1/29 scale environment, the mounted CamPac box and properly installed trucks having metal wheels can be seen below.


If choosing to use the car in 1/32 scale environment, the Kadee 1907 kit’s #1 scale smaller coupler could be fitted in the CamPac Boxes in place of the Kadee kit’s 907. (Note: The coupler in 1907 kit is described as centerset, but actually has downward offset to conform with #1 scale coupler railhead height.)





Mounting CamPac Box

Only a brief installation overview will be illustrated here. NOTE: For full "how to" installation detail, you must see the "PIKO 2 Bay Hopper Car CamPac Box Install Guide" on Colin Camarillo's website where the CamPac boxes for the Car can be obtained.

The chassis frame must first be re-installed, and the center of the spine must be screwed to the car body. This requires drilling and tapping before threading in a long screw. This is shown in the Install Guide.

The CamPac box "key" will be seated into the car's end sill slot.

With the box key seated within the slot, and whilst the box is firmly held in position, frame holes to be drilled and tapped can be established. The box can be removed to do the full drill thru and subsequent tapping.

With frame holes drilled thru, they then can be tapped for #2-56 thread.

Finally, with the held in place box and seated, it's fastened with #2-56 screws.




PIKO & Aristo-Craft Car Comparison

Shown below in BN livery is an Aristo covered hopper on the left and a PIKO hopper on the right with factory lid cover

Shown below are the top views of the same cars with Aristo covered hopper on the left and PIKO hopper on the right.

Shown below are end views of the same cars with PIKO hopper on the left and Aristo covered hopper on the right.




Upgrading PIKO Car to "Modern" Era

The example presented is the "Reindeer Pass Exclusive" car in BN green livery because it has the: "Clean, Oil, Test Stencil" (COTS) labeling having white outlined black panels indicating more "modern" era 1974 dates.

The picture below shows the car before the Aristo-Craft Barber emulated roller bearing trucks were installed - with the washers to be used over the bolster posts before trucks are mounted just like the Car with factory Bettendorf trucks.


The following pictures show the car with the Aristo-Craft Barber emulated roller bearing trucks installed.

The trucks have AML metal wheels as an alternative to the Aristo wheels. Because the plastic bearing caps fit a little loose, they were glued with a tiny amount of Titebond glue.


The "B" end of the car is shown below. Note that the more modern brake wheel could be placed over the molded-in brake lever - not yet done.


The "A" end of the car is shown below.


Because the Aristo Barber truck bolster mount hole is about 0.020 inch larger in diameter than the PIKO factory Bettendorf truck, a shim is made to fit within the hole, and then the truck is mounted as illustrated below. Doing this mitigates excessive car wobble.





Adding Pneumatic Brake Parts

The PIKO hopper car does not have any emulated pneumatic brake parts. A more contemporary brake assembly can be installed within the "B" end frame of the car - shown pre-painted.

This nicely 3-D printed assembly includes air tank, cylinder, and valve made by Nico Corbo. It can be obtained via Nico's website, 4TrackRR.



Shown below is the Reindeer Pass Exclusive PIKO hopper car brought into the more "modern" era, including gluing in Nico's brake assembly.



PIKO Car Weight Configurations









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