Coal hopper details – pt 2

Let’s dive into more hopper upgrade ideas. Part one in the previous blog post covered end post replacement, and grab iron and hand hold replacements. Are you ready for more?

Retainer valve and brake platform

I like adding the retainer valve and line to models. Before removing the Tichy retainer valve casting from the brake parts sprue, I drill a #80 hole and glue a short piece of 0.008-inch diameter wire in the back. The wire makes it easier to mount on models. It’s also easier to drill the part while it’s attached to the sprue.

I drill a #78 hole on the car end where the valve is mounted. The hole is large enough to also mount the 0.008-inch diameter wire air line. It takes patience and practice to point the other end of the retainer line to the air reservoir. It’s a neat detail when it’s done.

Brake platforms can vary in size and placement. The Bowser detail is mounted too high for non-Pennsy prototypes. I’ll modify the Bowser part but usually just make these from a strip of 2×10 styrene. I skim the ratchet detail from a Tichy brake platform part and add it to the styrene strip. The legs are 1×4 styrene strip that has been cut in half lengthwise.

The platforms are mounted where the slope and end sheets meet. It spans the space between the ladder post and an end post. I’ve seen a couple instances where the platform extends to the other end post.

Brake lever and fulcrum

The brake lever is visible under the slope sheet as it is connected to the brake cylinder clevis near the end sill. The lever hangs from a fulcrum attached to the bottom of the slope sheet. In most cases we can model a simple approximation of these details.

The three main parts are featured in the image above. I use a short length of styrene channel stock as a base for a triangular piece formed from scrap styrene. A short piece of 0.0125-inch diameter wire acts as the pivot attachment point for the brake lever. The lever is a length of 1×10 styrene trimmed to reflect the lever angles. I find it easier to make these than to modify the Tichy parts, which are a bit thick.

The channel and fulcrum piece is installed on the slope sheet, in line with the brake cylinder clevis.

It’s easy to slip the brake cylinder into place on the wire pivot and in the clevis. A small drop of styrene cement on both points holds the lever in place. I trim the length so it doesn’t interfere with the truck pivot.

Of course, not all applications are the same! The Pennsylvania Railroad used two strap metal pieces to form the brake lever fulcrum on many of their GLa class hoppers. These are anchored between angle stock on the slope sheet.

I did not install the pivot wire on this application. It was a tedious installation but I learned what to do better on the next attempt. I admit the angle stock I used here is oversize but it was at hand.

Sill steps and train line

The Bowser sill steps are heavy so I replaced them with A-Line style A flat wire steps.

Here’s a comparison on the sill step details. These are an easy upgrade for any plastic freight car model. I use a scrap piece of HO 12 x 12 styrene to align the step below the side sill.

Another detail can be seen in the image above. The Bowser models have a tow loop cast onto the bottom of the side sill. I noticed the Union Railroad hoppers had this in a different location. The plastic detail is easy to shave off. I formed 0.0125-inch diameter wire for the new detail on the Union hopper. Check your prototype for these details. There are variations, or there might not be a tow loop, which is what I noticed on Buffalo Rochester & Pittsburgh and Western Maryland prototypes.

Installing the air line is easy on these earlier hoppers. I use 0.015-inch diameter wire with 90-degree bends on the ends. The long segment should be about an inch-and-half long. I made a jig from scrap styrene to bend the wire and to mark attachment holes in the underframe. I use a short piece of 0.0125-inch diameter wire for the center support. I bend a short hook on one end to support the train line.

Uncoupling hardware

All prototype freight cars have hardware used to uncouple from another car. In many pre-1930 cases, this is a rod that has a few bends and rotates, pulling the top mounted pin to unlock the coupler.

I’ve been adding these details with wire and eyebolts for years. The rod had some different shapes, so take note in the prototype photos. The installation on the BR&P hopper was straightforward. Notice in the above photo that the rod is mounted close to the back of the end sill. The left end is bent over the end sill and is located between the poling pocket and the end grab iron. The right end is bent out over the coupler shank.

I bend 0.0125-inch diameter wire to shape and to fit the location. Eyebolts are used as anchors in holes drilled with a #78 bit. I install the left eyebolt first and thread the wire piece through. The right eyebolt is placed over the other end of the wire then wrestled into the mounting hole. It’s a bit tedious but you will quickly get the hang of it.


Study the prototype photos for the proper trucks to install. I try to pick a pair that best represents the prototype. The Bowser arch bar trucks follow a Pennsy design for their 2D-F1 class arch bar trucks, which were used under GLa hoppers into the 1930s. I also use the Tahoe Model Works AC&F arch bar truck under the Union hopper and the Kadee Andrews truck on the BR&P hopper.

USRA cars

I’ve only upgraded Accurail USRA hoppers as that’s what is in my stash. I have a few Tichy kits but following the instructions will end up with the as-built cars. Many of the Accurail grab iron and handhold upgrades are similar to those on the Bowser cars. I haven’t changed out the sill steps as they are a finer profile compared to the Bowser cars.

K brakes

The brake cylinder and lever casting can be kept with the Accurail cars. I install the air line connection to the air reservoir as it’s seen close to the end sill.

I only install the air line on the brake cylinder. The other end disappears into the shadows. I bent the line at the slope sheet support but it can probably end there.

Obviously, we can’t use the Accurail air reservoir kit part as it is for AB brake systems. I keep several packages of Tichy K brake detail parts. They make KC and KD versions. The KD has the air reservoir as a separate part.

I have a trove of the KC brake castings on hand. Modeling friends send their extras as they have a later focus when the AB systems were dominant. I slice the air reservoir away from the KC brake casting using a sharp single-edge razor blade. This is a tip from Al Westerfield that was featured on a Westerfield Models DVD with resin freight car building techniques. I roll the part while applying pressure. Use care to avoid damaging the fine details on the end of the casting.

I mount the air reservoir onto a mounting pad from the Tichy K brake sprue then add the strap of thin styrene that shows up in prototype photos. Once the glue has dried, touch up the new parts with a similar shade of paint. It’s easier to do this before installing the underframe.

Train line

The USRA hoppers had the trainline along the right sill and held by small brackets.

I trimmed a 0.015-inch diameter wire to fit between the end side stakes and drilled three mounting holes. I made small hooks from smaller wire to anchor the trainline along the side sill. Small tabs of 0.005-inch thick styrene are glued to the car side to represent the brackets. Remove any rivets on the car body that will interfere with the tab installation.

Once these tabs are in place, you could add Archer rivet decals for the rivets and bolt heads that are on the prototype details. I did that on a previous USRA hopper but those detail seem to disappear after applying the touch up paint.

Here’s the upgraded model with the details touched up and riding on Tahoe Model Works 50-ton Andrews trucks. Weathering will be next, followed by a new weigh date stencil, then air hoses and the Carmer uncoupling hardware will be installed.

More references

Dave Parker upgraded an HO scale MTH USRA hopper a few years ago on this blog. He also posted his Accurail USRA hopper upgrades.

Set your own bar and upgrade a few hoppers. The first couple are tedious but once you work through those, more upgrades become easier.

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6 thoughts on “Coal hopper details – pt 2”

  1. This is a wonderful tutorial Eric. Thanks! I have a general question. When you are adding these details to a car already painted, do you generally hand paint all these details once they are on the car? I can imagine that some of the items under the slope sheet can be real tough to reach on all sides, even with the underframe removed.

    1. Thanks, Andy! The details are touched up using a small brush. I am about to touch up a couple of these cars now with Vallejo Model Air Dark Grey Blue. It’s not a perfect match to the black car color, but the weathering layers will blend it together. The Model Air line covers well with a brush. It is much easier to touch up the new brake components before the under frame is glued onto the car body. This is a lesson learned on a couple of these models. – Eric H.

  2. Thank you Eric. Lots of good visible details to add to my Accurail and Bowser hoppers. I will try your technique for drilling out the retainer valve. In the past I have cut them from the sprue first and launched them into space wit the tweezers. Mr. Tichy said he would consider adding extra retaining valves to his brake sets, but it may not happen.
    John Sanders

  3. Eric,

    Appreciate all your work and sharing with us. I have found (inspired by alot of your work) that a part of the hobby I’m enjoying the most of presently is upgrading/accurately detailing freight cars.

    I am struggling to find any sketch/blueprint on the brake rigging, rods, & train line routing for Quad hoppers both in K Brake and AB. In particular PRR H21 and H22 style hoppers with Sawtooth or clam shell doors. Do you have any advice/suggestions? Im trying to find the nearest prototype to go crawl under and photo… I know alot of guys dont bother much with the levers as its very difficult to see them on hoppers versus box cars as example.. but I have a desire to at least attempt.

    1. Thanks for your comment, Brian! I do not have any detail on the brake rod details of your question, or a link to a diagram. I know they followed the center sill on hoppers. Brake rod positioning rarely changed when cars were upgraded to AB brakes from K systems.

      I fake the appearance by adding a piece of 0.0125-inch diameter wire along the center sill for the brake rod. It is anchored to the center sill on each end near the slope sheets by bending the wire at right angles. These short wire legs are glued into holes in the center sill. This can be seen with a low angle view of the hoppers. I don’t add the levers that transmit the rod movements to the brake hardware on the trucks. I hope this helps! – – Eric H.

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