I have had the unfortunate experience that one of my class 140's lost its lettering on one side. It simply fell off. I thought that I would use this as an experiment and try and fix the problem using decals.
So I started to search the web to find someone that could produce DB decals for me and with enough experience to do it the prototypically correct. I found Andreas Nothaft's home page and decided to send him a message asking if he could help me with the correct lettering. After a few mails back and forth about how the numbers should look like I got a testprint that I liked. I placed an order for a complete set of new numbers for the locomotive, even though only one number was damaged, I ordered more in case more numbers would fall off.
Putting on the decals was the same piece of cake as in the article about how to apply professionally looking decals and the result looks great. I have not yet tried to change the numbers on coaches and freight cars, but I might do that in the future. Of course I use my favourite decal remover and softener from Microscale Industries Inc. You should be able to buy this in almost any well assorted model train store.
I first use Micro Set to remove the old printing from the locomotive.
Then I apply the new decal from Andreas Nothaft. To create a nice and clean "printed on" look, I use the Micro Sol decal softener, which softens the decal to really make it blend in on the surface.
The finished result is almost as good as the real factory printed locomotive number. Anyway it will pass the 60 cm test (the distance from where the spectater will be looking at it), which is always good enough for me.
That's it! Of course this procedure will work on anything from locomotives and freightcars to model airplanes and trucks. I hope you enjoyed it! Throw me a comment and tell me what you think. :-)
Happy kit-bashing! :-)