STEP 5 WEATHERING DIAPHRAGMS
Making a mask – Diaphragms are flexible walkways between passenger cars. They’re built with steel frames and covered with a canvas bellows. They also take a heck of a beating in service, particularly the steel end plate. To rust up the end plate, I made paper masks that slid between the end plate and the end of the car and covered the doors.
Comparison – The car on the left has the dust coat applied to the end. The car on the right does not. I’d considered applying dust to the sides of the cars along the bottom edge as well, as I’ve used it on other cars to good effect. However, I decided against it here, as I liked the car-washer-clean look combined with the dirty undercarriage.
Paint the plate – To start the end plate rusting process, I airbrushed it with a 1:4 mix of Vallejo 71.026 US Flat Brown. I’m not entirely happy with the results of the thinned paint (full-strength would have been better), but I was attempting to protect the delicate end gate as much as possible without having to remove it.
Pastels for rust – The paint only got me so far for modeling rusty diaphragm end plates. Once the paint dried, I sprayed the car ends with Testor’s Dullcote, then applied three colors of Monroe Models pastel powders – 3105 Dark Rust, 3106 Light Rust, and 3107 Dark Earth. I scrubbed the pastels into the surface with a Microbrush.
Dust coat – Since I had the airbrush out, I also applied a coat of dust to the car ends. While the sides stayed fairly clean, the ends tended to pick up grime from dirt swirling between the cars. To apply the dust coat, I used a 1:5 mix of Vallejo 71.122 US Desert Tan. When thinned, this makes a subtle effect that is easy to build up in layers.
Before and after – When coupled into a train, the diaphragm plates rub against each other constantly and rust quickly. By using paint as a base coat, then three colors of powdered pastels, I got a satisfying effect of old and new rust. The diaphragm on the right is finished except for a shot of Dullcote to seal the powders.