Painting/Weathering Modern Gondola Interiors

If you actually look at most modern gondolas out there today, you’ll find that most open top cars from the last 30 years or so actually don’t have any interior paint or coating, but instead the interior of the cars are raw, unpainted steel (other than perhaps some overspray from the painting of the exterior of the car).

Of course, with some exceptions, most model cars do not reflect this and instead of masking and painting the interior a rust or brown colour (which would really still need to be painted/weathered for a proper rusty steel look anyway) the whole car, interior and exterior, is painted the body colour.

I was having a bit of a painting and weathering weekend this weekend, and got out this sextet of Atlas Trainman SIECO gondolas to paint the interiors “rust”.

Six Atlas Trainman gondolas with the interiors painted to look like bare steel with rust. (Exterior weathering still to be done in this shot.)

To get a good steel colour, I start by giving the inside of the cars a good base coat of Gun Metal. This gives a nice dark metallic colour as a base to work on. Then the rust colouring is added with several very thin coats of Rail Brown, Roof Brown and Rust. These brown/rust coats should be very light and thin, not going for solid coverage and allowing the lower colours to show through. The layers of colours and natural variation created by the light, uneven coats of brown/rust provide a nice rusty steel look.

I may complete the weathering with additional application of rust-coloured powders and some bits of debris from former loads, but the basic painting of the interior to change it from the main body colour (bright blue for the two GTW cars) to something that looks like unpainted steel really gets the cars popping with minimal effort.

Freight Car Friday # 69 – ONT 6051

While today’s Freight Car Friday subject isn’t an AC car, nor taken anywhere near the ACR, it is definitely related.

This shot courtesy of an antique show find by Keith MacCauley shows an almost brand-new Ontario Northland triple hopper # 6051. 72 of these cars numbered ONT 6000-6071 were built by National Steel Car in 1971 for use carrying iron ore from Adams Mine near Dane, ON to steel mills in Pennsylvania. Canadian National, Ontario Northland, and New York Central/Penn Central provided cars into a pool for this service, with many of the PC’s portion coming from the Toronto, Hamilton & Buffalo and Canada Southern Railways (although that’s clearly an actual PC car coupled at left in this photo). Given the freshness of the ONT car, the date is almost certainly summer 1971. We haven’t identified the location, but it’s likely somewhere in the States.

In the late 1970s this service ended, and these cars were disposed of by the Ontario Northland, with the Algoma Central picking up thirty of these cars in 1978. They would run for several years in original numbers with just the reporting marks patched out, and then in the mid 1980s these cars were renumbered from their 6000 series numbers to the 8600-8629 series.

Freight Car Friday #68 – CGTX 71506 Model

CGTX 71506 is the first addition to my (hopeful) fleet of tank cars for sulphuric acid service. Sulphuric acid is a common industrial chemical and a by-product of ore smelting operations. I’ve posted prototype photos in previous “Freight Car Friday” themed posts of acid cars running over the former ACR, likely from the operations at Timmins, ON or Rouyn-Noranda, QC via the Ontario Northland Railway through Hearst.

This model is a Tangent Scale Models car which was purchased as an undecorated/lettered but assembled and painted (black) model. The model represents a General American Transportation 8000 gallon car for acid service built in the late 1940s, but is very similar (identical in size and overall profile with only minor detail differences that you’d only notice if doing a direct side by side comparison of the model and prototype photo) to several older CGTX cars as well, so I was able to use it as a nice stand in. I’m unsure of the exact original build date of the CGTX cars but they would be from the same period – late 1940s-early 1950s and with railroad cars having about a 40-year lifespan, it’s plausible to be running out its last miles in the mid 1980s.

I didn’t actually change any details but just lettered the car following a late 1970s prototype photo with an old Herald King CGTX tank car decal set, with some additional detail lettering and COTS, ACI and U-1 decals to bring it up to a 1980s appearance from various Microscale sheets. With a little bit of in-service weathering, this car’s appearance will be completed and it will be ready to haul loads of acid from the smelters to industrial users in the central/mid-west USA.

Dating via the Details: General Car Design

Here we must necessarily deal with generalities rather than specifics, but even if you’re not too particular about making sure every car is totally appropriate for a specific year, you can help create the impression of a general time frame by at least choosing appropriate rolling stock. To get fully accurate by era equipment, research on the specific car(s) on an individual or series basis would be required, to determine if the specific railroad paint scheme is era-appropriate (e.g. a 1970s car but with a 1990s repaint), or if a particular car or series hadn’t been sold off (or conversely, acquired from a secondhand source) by a certain date, or whether a model is even accurate in the first place for a particular railway, but this should at least give an “at a glance” view of the evolution of the North American freight car fleet, although by necessity not every detail can be covered.

Car Designs and Sizes

Some interesting dates for the introduction of certain types of cars:

1948 – mechanical refrigerators placed in service by FGE

1955 – Airslide covered hopper introduced

1959 – 85′ flatcars with kingpins (TOFC) introduced

1960 – trilevel autoracks introduced

1967 – Thrall introduces all door boxcar

1973 – first enclosed trilevel autoracks

60 and 86 foot “high cube” boxcars were built for specialized services (primarily auto parts – especially bulky steel body panels from centralized stamping plants to assembly plants) in the 1960s and 1970s.

AAR “Clearance Plates” are clearance diagrams that show the maximum external dimensions for railway equipment in order to stay within standard clearances. Larger standard “plates” have been added over the years:

1948 – Plate B adopted, max height 15’1″

1963 – Plate C adopted, max. height 15’6″

1974 – Plate E adopted, max. height 15’9″

1974 – Plate G adopted, max. height 17’0″

1975 – Plate H adopted, max. height 20’2″

(Of course the clearance plate is full cross-sectional profile, not just a max. height – the outline of the common NMRA standards gauge is basically the Plate H clearance diagram.)

Most 50′ boxcars built up to the early 1970s fit the Plate B clearance (although a lot of Plate C cars were built in the 1960s – especially Canadian newsprint service boxcars). By the mid 1970s Plate C was standard and Plate B boxcars were essentially no longer built. (While early RailBox cars were Plate B, the common picture people have of the standard “RailBox” style boxcar is a late 1970s, exterior-post construction Plate C boxcar.) As of the 2000s, pretty much all new boxcar construction (and yes, new boxcars are still being built by the thousands every year) are 50′ single door or 60′ double door Plate G high-cube designs.

Service Life

Much of the information above deals with the introduction of car types and designs; but an individual car can last in service for decades.

For cars built before July 1974, service life in interchange service is limited to 40 years.

For cars built after July 1974 service life in interchange service is 50 years, although this can be extended to 65 years with a rebuild or mechanical certification (some groups of TTX autorack flatcars have received a blanket certification for 65 years service).

Underframes

The earliest freight cars were built entirely from wood. Sometime around 1910 car builders started moving to steel under frames (but still using wood or mostly wood bodies) for most types of freight cars such as boxcars, flatcars, etc. Most hopper and tank cars were all-steel construction by this point however.

By 1928 wooden main sill underframes were banned from interchange. Truss rod reinforced underframes (new or retrofitted) were still legal until 1940 when all wood underframes were outlawed from interchange service.

Dating via the Details: Wheels, Running Boards and Ladders

In a previous post, we looked at data, stencils and lettering that can update or firmly root a car’s appearance to a 1970s or newer time frame. Here we’ll look at some of the concurrent physical changes to freight car hardware (and rules regarding the same) that will also help indicate the modeled time frame.

Running Boards, Ladders, and Handbrakes

Model of a modern (1974-built) boxcar built with low ladders and no running boards (roofwalk). The “ribbed” outside-post construction of this car is also a post-1960s signature.

The earliest railroad boxcars featured handbrakes that were operated via means of a wheel attached to a vertically-mounted brake staff that would be operated by a brakeman walking on wooden running boards down the centre of the car’s roof.

While automatic air brake technology was introduced and improved during the late 1800s, this arrangement stuck around, with the handbrake to tie down a parked car still located at the top of the car end, and running boards (later made of steel instead of wood) to allow brakemen to move down a cut of cars to set (or release) multiple hand brakes.

The first major change in rules regarding running boards came in 1945 when wood walkways outlawed on new cars. New cars were to feature expanded metal running boards, but the wood walkways were generally not replaced on older cars. (Obviously metal running boards would have existed before this but I don’t have any “first” dates of adoption.)

The most significant change came in 1966 when the rules were changed to no longer require running boards. New cars ordered after 4/66 or delivered after 10/66 were required to be built without running boards and low-mounted handbrakes. Running boards also began to be removed from cars, with the original target date for completion being 1974, but full compliance lagged behind a bit. By 1982 walkways were banned on boxcars and reefers in interchange service in the US.

Older 1940s built boxcar that has been upgraded and modernized to remove running boards (although the former supports are very much in evidence) and cut down ladders. On this car the brake gear has also been lowered, however on many cars the brake wheel was left in its original position, with full height ladders remaining on the “B” end corners to reach the handbrake.

 

Journal Bearings

50 ton truck with plain bearings (left) vs modern 100 ton truck with roller bearings (right)

Railroad car axle bearings came in two distinct “flavours”. The old style featured a solid axle end which turned on brass bearing inserts inside an oil-filled journal box cast as part of the truck. This is what is known in the trade as a “plain” bearing – sometimes also referred to as “friction” bearings, although only after roller bearings became common. Modern railway axles use a self-contained, sealed package of roller bearings

Some lists of dates show the first usage of roller bearings on motor cars and some steam engines and freight cars in 1923 and first roller bearing on passenger equipment around 1926.

As far as I can tell from trolling through several lists of important dates, the first significant regulations about roller bearing journals came in the 1970s, with roller bearings required for all cars with 6 1/2″ by 11″ journals in 1972 and  roller bearings required for all cars with axle loading greater than 55,000 lbs in 1974. (Basically, larger 90-100+ ton capacity cars being built then.)

By 1991 all cars in hazardous materials service must be equipped with roller bearings and may not be equipped with plain bearings and in 1995 plain bearings were banned from interchange entirely.

Trucks

The earliest freight car trucks were wood beam trucks with a heavy wood beam upper member and cast iron or steel journal boxes, spring hangers, bracing and other hardware. By 1870 “archbar” truck frames fashioned from heavy steel bar bolted together started replacing wood beam trucks as standard. Later trucks used various types of cast sideframes. Archbar trucks were banned from interchange service after July 1, 1940.

By 1958 all trucks applied to new cars were required to have AAR approved side frames with U-shaped castings and integral journal boxes. Cast truck side frames with T, I, or L shaped cross sections were prohibited under cars in interchange service.

Wheels

The last few changes are harder to note quickly from a distance as they’re underneath the car, but can still be seen in a side view.

Ribbed-back cast iron wheels (left) vs steel wheels (right)

Modelers may have noted that there are generally two styles of wheels available with some model trucks available (either as replacement trucks or included in some full kits or RTR models). Some wheels have a fancy-looking ribbed back appearance, while others have a profiled but plain back face such as the truck at top right in the photo. (Of course, some model wheelsets also have a completely smooth undetailed [inaccurate] flat-backed design….)

The ribbed back wheels represent older cast iron (not steel) wheels. Cast iron wheels were hardened in chilled water. To withstand this process the had ribbed backs. Steel wheels did not require or have these ribs.

As of January 1st, 1958 cast iron wheels were banned from new and rebuilt cars,  From January 1st, 1964 no new cast iron cars were allowed on existing cars, and from January 1st, 1968 all cast iron wheels were banned from interchange.

This is also a good place however to mention different sizes of wheels. Generally speaking, most older freight cars had used 33″ diameter wheels. However cars of 100 tons capacity or above rode on larger 36″ diameter wheels. Many modern trilevel autorack cars ride on low profile 28″ wheels. If you’re replacing wheels on your model freight cars and aren’t quite sure whether you should be using 33″ or 36″ wheels, take a look at the CAPY or LD LMT data lines below the car number. If those numbers are around 200,000 (lbs) or above, use 36″ wheels. Around 150,000 (lbs) is a 70-ton car likely with 33″ wheels.

Brake Systems

KC brake piping diagram

The first Westinghouse air brakes were patented in 1869.

In the early part of the 20th century, the common air brake systems in use on freight equipment (known as K or KC brakes) were a simplified affair where the brake cylinder, air reservoir and control valve were all combined as one unit. The more modern air brake system design (known as AB brake systems) that most people will be more familiar with are quite visibly different, with separate components for the brake piston, control valve, and a large air reservoir with separate halves for service [regular] and emergency brake applications.

In 1933 AB brakes were required on all new cars and the older K/KC brake systems were outlawed from interchange service in 1953.

AB brake piping diagram