I usually finish painting and weathering the truck assemblies well before the car body.  The Tamiya Metal Primer applied beforehand (see AT&SF Bx-14 BOX CAR: Pt1) dries quickly and one could start painting the wheels and trucks in as little as an hour later, but I wait overnight as a minimum.

The wheels are installed in a painting fixture along with a small ball of tacky putty (LePage Fun-Tak poster putty) on each journal tip.  The Tahoe Model works trucks, not a strictly exact Andrews truck for this build, are mounted on 1/8” diameter styrene rods.  If they fit loosely, I wrap a very short piece of Tamiya Tape on the end of the rod for more interference.

SETTINGS:

GREX Xb airbrush with .30mm tip, ~15-20 psi*, 1-2” away from model surfaces.

*a .30mm[.012”] tip is smaller than typical for most double-action airbrushes.  Most have a .50mm[.020”] tip which is much larger (2.8x greater in cross-sectional area) and therefore could use less air pressure.

Except for one color, all paint used is Tamiya XF which is thinned using their X-20A (for Acrylic – confusingly, Tamiya also calls its thinner for enamels X-20). 

For efficiency, I spray the colors in a certain order…

  • My mixture for AT&SF mineral brown (XF-9 Hull Red 1 part + XF-7 Red 2 parts) is airbrushed onto the trucks.
  • XF-24 Dark Grey (my substitute for Polly Scale Grimy Black), normally thinned, is airbrushed onto all exposed wheel surfaces.
  • The remaining XF-24 in the paint cup is then thinned considerably (1:1 or more) by adding more X-20A.  It is then lightly sprayed onto the top and bottom of the trucks.
  • XF-52 Earth, thinned normally, is mottled (applied patchy) on the wheels to represent uneven rust.  I then get up close to the truck springs and give them a couple of shots of this color for rust effect.
  • A little Polly Scale Oily Black is normally thinned with distilled water using the same procedure noted above.  This paint is no longer available, but I have one stash bottle and a little left in another**.

**I still need to find how to create this wonderful weathering color with Tamiya XF paint.  I’m thinking of mixing XF-1 Flat Black + XF-10 Flat Brown + XF-62 Olive Drab in equal amounts.  When I find something I like will post it.

  • Like the truck springs, I get up close to the journal boxes and spritz them with the Oily Black on all sides.

I leave all this to dry overnight.

Next day, I give the wheels and trucks an oil wash.  I use Abteilung 502 ABT110 Black (or ABT005 Smoke) along with their ABT111 Odourless Thinner.  I apply a thin wash overall, but then go back to the journal boxes with a somewhat thicker mixture.  I also pin-wash the spring recesses, journal box covers, and other details.  I leave this to dry overnight.

The day after that, I very lightly dry brush (see Category: TIPS – MODELLING/DRY BRUSHING) the trucks with Tamiya XF-57 Buff.  Before assembling the wheels, I clean the treads with Q-tip dipped in lacquer thinner.

If the trucks are painted black (XF-69 NATO Black), I do the same procedure except I prefer to dry brush with Tamiya XF-53 Neutral Grey instead of Buff.

Next post: Pre-Weathering Car Body