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Kid With an Airbrush
Hello all,

I recently bought a new old stock Stewart RS12 and am planning on stripping and painting the model into Seaboard Air Line. I have done some painting in the past, but nothing that required me to paint curved lines as the Seaboard's switcher scheme has. Here is a picture.

I will have no problem with the stripes on the ends as there are decals for that. I will however have a problem with the curve in the middle of the locomotive where the red meets the black. Does anyone have any advice on how to go about painting that? I'd imagine that the answer is going to involve some masking tape, so a specific technique to use would be very helpful.

Btw this is my first post, but I assure you it will not be my last. I can tell that this is a good forum.



Narrow Gauge Logging Nut
One way to do it is to mask it off, lay out your scheme then cut away everything that doesn't look like it belongs there. :)
That's how I always did it.


Master Mechanic
I form my curved lines using one of several techniques, depending on the situation.

Situation 1. The curve is long and fairly gentle. I use one piece of tape that has been laid out on a piece of glass, and following a lettering diagram, cut the curve out of one piece. Then cover the rest of the area not to be painted with additional full tape strips.

Situation 2. Take a piece of tape, and cut off a strip of tape approximately 1/16" wide. Then lay this tape down on to the model following a diagram, which in most cases, can be done by sight only. After the proper curve is taped, lay other pieces of tape over the back part to form a complete mask.

Situation 3. (I use this more often than not.) Place a piece of tape on to a glass, like the type of glass from an 8"x10" photo frame. Cut strips out of the glass, approximately 1/2" long and 1/16" wide. Lay each piece down to form the mask line and the cover with another piece of tape to form a mash about 1/4"-1/2" wide. Then use additional pieces of full size tape to form the rest of the mask, or substitute a final piece of clean paper to form around the body to finish the mask.


Kid With an Airbrush

I will probably do either one or two as that seems the most straight forward.

Thank you!


Master Mechanic
Even under the best of circumstances, I never had any real success using Micro-Mask. Being a latex product, it had a tendency to sometimes not peel off all the way, or when it did peel off, the line left was still more ragged than with tape, due to it leaving some of the paint behind when peeled off.


Active Member

For that red area in front of the cab, I'd apply it as a decal. Spray some blank decal paper with the red of your choice cut out what you want and apply it to the loco. It should work fairly well as there are no doors, ridges, humps or bumps in that area just a small section of louvers to deal with, but decal setting solution will take care of that.

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Kid With an Airbrush
Pretty well all of my paint is water based so the micro mask is likely a no-go, but I'll keep that in mind for future projects!


Wow that is a really great idea, I would never have though of that. I'm think I might just give that a try.



Kid With an Airbrush
Just figured I'd show yall how it turned out. I was going to cut a decal for it but my LHS was out of decal paper. So instead I free handed the curve based a picture and then traced that onto some masking tape. This was the result.


I think it's turning out pretty good, so long as you don't notice that the decals are a different color than the paint. Haha oh well, not my fault.

Thanks again for the help guys!

Burlington Bob

Well-Known Member
By chestateegol:

I think it's turning out pretty good, so long as you don't notice that the decals are a different color than the paint.

I agree and a little judicious use of weathering can help hide the color differences.

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