A recent swap meet found me with an Overland SD60 (i bought it for the mechanism, but it came with a Rail Power Products shell) that i intend to model for either a SOO SD60M or a CN SD60F. The mechanism is still brass (never painted), but i’ve never painted brass before. A friend told me that brass locomotives come with a clear lacquer to protect the finish (that kind of makes sense, because wouldn’t it tarnish otherwise?) I am wondering how i should prep the surface before airbrushing it (i plan to use Tamiya flat black). Any thoughts would really be appreciated. Thanks.
My experience has been that if the lacquer is in good shape, wash the piece in warm soapy water and then soak in straight vinegar overnight. Rinse with warm water and then I blow dry with air, so there are no water spots. I then use regular “rattle can” gray primer. I have never had a problem, but, it could react with some lacquers, so I paint the inside of whatever it is first, to see if there will be an issue. I have also used acrylic Badger Modelflex as primer without any problems.
If the lacquer is in bad shape, I’ve used lacquer thinner to wipe down or soak the piece to clean the crud off. Careful with lacquer thinner, it stinks to high Heaven and is nasty stuff.
You can also sand/bead blast, but, I’ve never done that as I don’t have the right equipment for that process.
Since the shell appears to be plastic, I assume you are talking about the frame. Personally, after I stripped the mechanism off and cleaned off any oil/grease, I’d rattle-can gray and then use the Tamiya paint. The shell will be covering most of it, so any rough spots will likely be out of sight. The fuel tank will be the most obvious part, I would think, so that will need to be smooth.
Hope this helps.
The other response is spot on.
Please note that you have an Overland chassis (not a brass locomotive) with a RPP shell. Overland sold a number of different chassis at the time RPP was offering shells. The Overland chassis were die-cast zinc alloy. Here are instructions for preparing die cast zinc alloy for painting from Bowser’s website:
TIP 1: Painting Metal
You may want to superdetail your loco before painting.
We suggest that you do not paint your loco until it is thoroughly track tested as disassembly and handling generally ruins a paint job. Take your locomotive apart so that the various parts may be painted without getting paint on moving parts. Valve gear, side rods, bearings, pony truck, etc. will not operate properly if paint gets into the joints of moving parts.
Parts to be painted should be degreased with a solvent like paint thinner and pickled in acetic acid solution (vinegar) or oxalic acid solution (5%) for a few minutes before applying paint.
DO NOT USE THIS VINEGAR FOR COOKING OR EATING.
Rinse with clean water. Do not handle the surfaces to be painted. CAUTION: Do not immerse wheels, underframe or cover plate in acid solution or cleaners. Brush cleaner and acid solutions on metal frames of lead and trailing trucks and on underframe surfaces to be painted (NOT ON WHEELS, AXLES OR BEARING SLOTS). Drivers are pre-blackened and can be touched up, after removing flash, without using cleaner or acid. I recommend a glossy paint be used (PRR locos were painted Brunswick Green). Apply a smooth, uniform coat of good grade model railroad paint. I like to spray paint my models. Work car
Surface preparation is everything. Any trace of grease, oil, fingerprints, lube oil, and the paint won’t stick. If the existing lacquer is in good shape (smooth and sticking well) I’d be tempted to leave it in place and paint over it. Hot soapy water, plenty of brushing, a clean water rinse, plenty of air dry will deal with grease and oil. If you are down to bare metal, an acid etch (super market vinegar works fine) will put some tooth in the surface for the paint to grab onto. Don’t touch the cleaned model with your bare hands, the finger print oils will spoil the paint bond.
The auto parts store’s carry primer in rattle cans. This stuff has the best chemistry the industry knows off to make it stick to metal and cover well. Use the light gray under light colored top coats (yellow for instance) the dark gray under darker top coats and red under red and maroon topcoats.