Discussion related to everything about model railroading, from layout design and planning, to reviews of related model tools and equipment. Discussion includes O, S, HO, N and Z, as well as narrow gauge topics. Also includes discussion of traditional "toy train" and "collector" topics such as Lionel, American Flyer, Marx, and others. Also includes discussion of outdoor garden railways and live steamers.
Discussion related to everything about model railroading, from layout design and planning, to reviews of related model tools and equipment. Discussion includes O, S, HO, N and Z, as well as narrow gauge topics. Also includes discussion of traditional "toy train" and "collector" topics such as Lionel, American Flyer, Marx, and others. Also includes discussion of outdoor garden railways and live steamers.
Recently aquired a brass diesel --Alco Models output of a C630 -- and want to paint it for RDG. It had tarnish all over. So I let it soak overnight in vinegar. Followed up with a detergent and water bath and scrubbing with a toothbrush. Applied primer and when that was dry a coat of cream color paint. While appying masking tape, paint peeled back to bare brass when I attempted to reposition the tape. (And I used high-quality3M brand tape marketed for automotive re-painting/detailing/customizing.)
What's the secret to removing the tarnish and getting a surface that will "grab and hold" the primer?
Also, a lot depend on what type of paint you are using. I have used regular Floquil and Scalecoat and baked the paint on prior to using tape without any paint lifting. Also by using Scalecoat you do not need primer nor a gloss finish coat for your decals, thereby reducing the paint thickness.
Another thing that can be used for blasting is baking soda which is biodegradeable and very cheap.
Also, I use drafting tape for masking as it is less sticky and does not usually lift off the paint.
Generally, unpainted brass engines have a coat of clear lacquer applied at the factory. This coat should be removed before painting. I generally soak my brass (and only brass or metal, NO plastic) in lacquer thinner.
I then clean the locomotive in an ultrasonic cleaner, since the metal has to be ABSOLUTELY clean for paint to adhere. Once the model is cleaned, it should NOT be touched until at least the first coat is applied. Touching the model will deposit oil on the model, which makes for poor paint adhesion. The suggestion to quartz blast the model is also a good one.
I paint the model IMMEDIATELY after the model has been dried after the cleaning process. This minimizes the possibility of tarnish and other oxidation products reforming on the model. I usually wait one week after applying the first coat of paint (usually the primer, like zinc chromate) before applying another coat to the model. This waiting or drying process should be done in an dustless atmosphere.
Again, the secret to successful application of paint on brass is cleanliness.
