Tank car weathering

Rapido Model Trains recently released their model of the Procor GP20 20,000 gallon general purpose tank car.  This has long been on my list of "must have" models for the Hudson Bay Railway.  Any photo with a tank car in it from the late 1970's to the 1990's was likely one of these cars.  They were used to haul gasoline, diesel and other fuel to various parts of the northern railway network.  They were used to stock the fuel tank farm in Churchill that serviced the barges that supplied communities along Hudsons Bay.  This required massive numbers of tank cars to travel north.  

The model from Rapido is very nicely done with etched walkways and nicely rendered fine details.  They are pretty much ready to go out of the box, however I want to try adding some weathering to the cars to better represent the prototype.  

One challenge is that there are not that many photographs of these cars in service in the early 1980's, as much due to the cost of a roll of film as at the time they were "just another black tankcar".  My friend Mark P. did take a few slides of these cars in service so I used these as a guide to weathering.  

These cars were around 10 years old in my modelling era so they would be a bit weathered but still in relatively decent condition.  At the time less attention was paid to not spilling fuel so often they had oil/fuel staining around the center of the car.  There was also sometimes some rust starting to show through, particularly on the lettering.  

I first gave the cars a couple of coats of Tamiya TS-80 matte spray to kill the factory shine.  This in itself greatly enhances the realism of the cars as they didn't stay shiny for very long after coming out of the factory.  

On the Procor car I applied a wash of light rust over  the entire car to give it a bit of a brownish rusty tone.  I followed this we a bit of Pan Pastel weathering to get some streaking on the carbody.  I also weathered the trucks to get a bit of road grime and rust on them.  

The North American car only got Pan Pastels with various shades of brown, grey and umber applied, also going for a streaked weathered appearance.  The trucks on this car got a grey brown application of Pan Pastels.  

I used a number of Vallejo Weathering Effects oil stains applied.  On the North American car they worked well, giving a nice oily finish on the car.  For whatever reason the Procor car only got the oily staining along the edges of the applied area, with the center portion essentially disappearing.  I fixed this with an application of Vallejo gloss varnish blended into the edges.  It gives the appearance of multiple spills which works fairly well.  

I swapped out the Rapido couplers for Kadee #158 scale head couplers.  For whatever reason Rapido decided to have some small protruding supports at the rear of the coupler pocket.  This requires a bit of filing on the rear of the Kadee coupler to fit properly.  

I painted the airhose glad hands with silver paint and the tank cars are ready for service.  I have another dozen or so GP20 tankcars to still be weathered but I think this approach works well.  I may try some other weathering methods to get some variety to the fleet.  I may try using oil paint as it can be very effective, both as a pin wash as well as for general weathering.  

One effect I want to try and capture is wheel spray on the bottom and ends of tank cars.  I have some ideas but need to see if I can accomplish this to my satisfaction.  Hopefully more to come. 

I gave this car a series of rust washes to get the reddish black colour of tank cars that are starting to get a bit long in the tooth.  This car didn't get the oil spillage as not every car had  this feature.

I thought I would give one car an oil paint pin wash to see if I could do it.  I watched a few videos from some of the military modellers who use this approach and it looks interesting.  I sprayed the cars with Tamiya TS-80 matte for the base coat.  I used a raw umber, raw sienna, burnt umber and burnt sienna artist oils for the pin wash.  This was all blended with odorless mineral spirits.  

I wanted to have some paint failure on the top of the car as I have seen this on some prototype cars and I like the look of it.  I used burnt sienna along the top of the car and used a makeup sponge to get the paint failure effect.  Overall I am pleased with the result and will use this on future projects.  I won't have the entire fleet this rough but a few cars like this add some variety.