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Sidewall of my Sn3 pilot model.

Sidewall of my S-scale pilot model


    DURANGO and GUNNISON Roundhouse in On3!

    I'm taking digital pictures of my progress on the O-scale roundhouse models as I go and posting them here on my web site. It's more a scapbook than it is a well organized essay at this point. Perhaps later when I have the time- Note that this is a work in progress and not all sections are posted at this time.

        Durango Roundhouse Kit Page    



        Durango Prototype    

        Gunnison Prototype    


        Durango 2006 Convention    

        Constructing the Patterns    

        Mold Making    

        Casting Hydrocal    

        The Floor Plan    

        Constructing the Base    

        The Inspection Pits    

        Fitting the Parts   


      Coloring Brick and Stone    

        Building the Roof    

        The Engine Doors    

        Final Assembly    

        The Boiler House    

        Foreman's Office and Crew Room    

        Additional Details    


        Gunnison Notes    

        The Pilot Model Display    


color tests

Delta Ceramcoat comes in all colors.

    My traditional method for coloring the Hydrocal castings as explained in my   Crow's How 2 section of the web site. These start by sealing the castings (after you have done all the cutting and fitting) and then use Floquil paints and stains. Since the stains have been discontinued and my supply is just about out I thought it was time to seriously look for alternatives. I'd tired acrylics (Polly-Scale) in the past but always felt the Floquil's looked better. Now that a one ounce bottle of Floquil acrylic retails for $4.99 and the solvent based paint is fifty cents less it's time to wake up.

    There's nothing special about Floquil. Yeah, they mix up your favorite railroad colors but we can find the same thing for one tenth, YES, ONE-TENTH THE PRICE. 99 cents for a 2 ounce bottle in just about any color you want. You'll find them under several brand names. I chose Delta Ceramcoat but they are inter-mixable with all the others. Liquitex and Golden both manufacture preimum grades and tube paint if you want to go that route but there's nothing wrong with the cheap ones for painting or should I say staining our Hydrocal castings. They are simply an inexpensive thin gel acrylic paint that should be available at your local crafts store. I went to Micheal's here in Seattle for mine.

    There's a whole rainbow of colors to choose from. Actually it's not too hard to mix your own. there's even a science to it, starting with the primary colors of red, yellow and blue. From them you can mix any color you want. Half red and half yellow gives you orange and so on. Add white and black to make them lighter or darker. But of course it is easier to buy the colors we need per-mixed and at a buck per shot- why not?

    For the stone we'll start off with a neautral base color. So look for something that looks like the natural stone, either a light gray, tan or whatever. Also consider your scenery. What have you chosen there? More than likely the stones for the building were gathered locally so they should match. We'll also highlight some of the stones with other colors mimicing those old Flo-Stains- walnut, teak, a little mahogany.

    We'll do the same thing for the brick. Orange, red, brown... Pick a few of those.

    Here are some of the colors I brought home. As mentioned I bought the primary colors of red, yellow, blue, black and white. I picked up a green too. I got a couple of greys for the stone. Some tans and light browns. Then for the brick I got Tuscan red, golden brown and stuff like that. I also brought home the standard Burnt Umber, Raw Umber, Raw Sienna and Burnt Sienna.

    Now we can run some tests!

color tests

Color tests on a spare stone wall.

    For the stone I started off with a grey. I thinned the paint with water and simply brushed it on. Note that I did not seal the casting first. We'll let the acrylic paint do that. Next I painted individual stones at random with the highlight colors (sandstone, Payne's grey, brown (oxide red) and toffee brown). I wisely wrote down what I was doing on the back side of the test panel so I'll have a written record of exactly what I did. With so many colors it's easy to get mixed up. For instance now, a month later I'm struggling to remembewr which grey I used on the roundhouse foundation. Quaker Grey? Dolphine Grey? Or was it Rain Grey? Well, it was one of those. The point is WRITE IT DOWN and really it's up to you to decide what color you like most.

color tests

Start with a base coat of grey. Here I'm testing three different shades.

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Highlight ome of the individual stones.

color tests

Looking pretty good.

    Next step is to see if we can improve the results. The wall looks okay at this point but I want to see if I can do better. We'll try a wash of ink stains. Acrylic stain. How about some Builders In Scale Silverwood? Or mortar mix? I applied some acrylic gloss medium to make the stones shineier.

color tests

Let's try some different finishing techniques.

color tests

I've wisely written down notes on the back of the test panel.

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Test panel A.

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Test panel B.

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Test panel C.

color tests

Here I'm refining the technique that I most like.

    I'm looking for something that is quick and easy, not too complicated. If you were a real artist you could sit down and paint each stone. But this seems to work. I decided I liked the grey base, a few random stones with color (don't worry if they aren't precise), a gloss overcoat, then a SilverWood wash.

    I did similar tests on the brick using various reds and browns. Burth Sienna was my favorite.

color tests

Color tests for brick.

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Color tests for brick.

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Here's the one I like.

    To finish them I used a thin wash of Builders In Scale mortar mix. Initially I over-applied the mortar mix which is my custom on HO models. However, after applying it thick to the inside walls I came to my senses and did it very thinnly to the exterior. It's a light-grey and we don't have to fill in the mortar lines, just accent them. Mix only a little at a time. Here I'm using a brush. Then wipe the excess away with a paper towel and polish the surface.

    So, let's review the technique:

color tests

Squirt a little paint into a mixing cup.

color tests     color tests

Add some water, be consistant.

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Apply to the wall. A little streaking is okay.

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Cover the whole wall.

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side wall.

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mixing the mortar

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spread it out

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blot and polish

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finished side wall.

    The saw-toothed corbels were a bit of a challange. Easy does it and do a little at a time. The mortar mix lightens up considerably so keep an eye on it as you proceed.

color tests

Applying mortar to the corbels.

color tests

    Now, this is not the only way to do it. As I first mentioned I've always been pleased with Floquil solvent based paints. Other brands will likely work just as well. You may already have your favorite method down or like that of another manyfacturer or modeling author. Glenn for instance used the same basic techniques on his Gunnison roundhouse model but chose to do them darker, capturing the "Black Canyon of the Gunnison". That's the thing, do what you think is right.

    With the cost savings, ease of use, lack of nasty solvents- All in all I'd say acrylics are the way to go. Though I do not recommend it I also found cutting the finished castings is possible. More so than with the rock hard finish of sealing and painting. I had miscalculated the corner pieces of the rear wall and needed to trim them which I did without cursing. You really want to do the rough work before painting and finishing.



    Next section:     Building the Roof    



    Limited Run - O Scale    

    Future Kits - O Scale    

    Scratch-Building Stock Panels   


  C. C. CROW     P. O. BOX 1427      MUKILTEO, WA   98275   USA