There can be all sorts of reasons that a freight car would exhibit a paint patch, but by far the most common, in the transition era, were the dual requirements to restencil cars that either had been reweighed or had journals repacked. I will show a prototype example or two.
First is this DT&I gondola with a load of auto frames (photo from the Richard Hendrickson collection). Its light weight and load limit have both been changed (one cannot change without the other, as their sum is a fixed value), along with the date and place of reweighing; and toward the far end, the repacking stencil has also been renewed on a paint patch. (As with all these photos, you can click on the image to enlarge it if you wish.)
Sometimes larger areas have received paint patches, when other data have changed or the railroad changes some other aspect of the lettering. The Grand Trunk 40-foot automobile car below is an example (again, Richard Hendrickson collection). At right, dimensional data as well as repack stencil have been renewed. At left also, several items are patched and re-stenciled.
These paint patches are common enough that they cry out to be modeled. One can easily model them by using a fine brush to paint a rectangle of the desired color in the appropriate place on the model, then add a coat of gloss for decal application. But it turns out it is not so easy to paint a little rectangle with crisp corners. To do that, one answer is decals.
The extremely useful reweigh decal sets once offered by Sunshine Models contained panels of freight car color, which were black, brownish red, and chestnut red. I show examples of them below. These were printed by Rail Graphics (now out of business) for Sunshine. The long dimension of each panel is about 2.25 inches.
Using these, of course, is very simple. Cut out the appropriate rectangle, apply to model, and apply the needed reweigh or repack information over it. It hardly needs stating that these decals panels are no longer available — though someone else could offer them.
But what is the answer if you don’t have the Sunshine panels, and would like panels in colors like these? And even if you do have the Sunshine panels, what if you need a color different from the ones you see above? Maybe the railroad you model had freight cars of different colors from the ones above, or perhaps you need to add a reweigh panel to a yellow reefer.
One solution is to save the blank ends or edges from decal sets, which often have a blank area (if you have it, of course, you can use a whole sheet of blank decal paper) and then paint it the color you want. For the example I used above, of needing yellow, I took an old decal set edge and painted it with Testor’s Gloss Yellow from the rattle can. It’s held here with a normally-closed tweezer, not because it’s hard to
hold, but to give it weight while it dries in the sun outdoors.
Obviously any paint color, via airbrush or rattle can, can be used to make panels in the same way.
Many authors, including me, have posted or written magazine articles previously about how these paint patches can be used on model freight cars. One example is my article, “Reweigh dates on freight cars,” in Railroad Model Craftsman in April 2011, and reprinted (with corrections) in Model Railroad Hobbyist in February 2020 (you can read my post about all this at: https://modelingthesp.blogspot.com/2020/02/a-small-article-in-new-mrh.html ). In a future post, I will show some examples of how I use these paint patch panels.