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  P.   O.   B O X   1 4 2 7         M U K I L T E O,     W A     9 8 2 7 5     U S A    

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    

        Making Molds    


      Casting Hydrocal    

        The Floor Plan    

        Constructing the Base    

        The Inspection Pits    

        Fitting the Parts    

        Coloring Brick and Stone    

        Building the Roofs    

        The Engine Doors    

        Final Assembly    

        The Boiler House    

        Foreman's Office and Crew Room    

        Additional Details    


        Gunnison Notes    

        The Pilot Model Display    


    So now we can start castings. I'm always excited about new molds. I've been working on these patterns for months now so finally we can start pouring and make dozens of them if we want.

Durango rounhouse construction.

Durango rounhouse. Mold sink. Don't do this in the kitchen sink. Not if you want your wife to ever talk to you again. I've plumbed in an old sink and have a trap underneath it to catch all the plaster chunks and yuk.

Durango rounhouse construction.

Here's the trap. About once a year it needs to be cleaned out. One of those dirtiest jobs you see on TV.

Durango rounhouse construction.

Close-up of a four pocket mold. These are for Gunnison's front portal.

Durango rounhouse construction.

I've just poured the Hydrocal in these molds and tapped them vigorously to help remove any trapped air bubbles. In a moment they will begin to harden.

Durango rounhouse construction.

Before the Hydrocal gets too hard the backs are scraped smooth. It must be done gently on the HS II as it is much softer than the 3110 rubber I'm used to.

Durango rounhouse construction.

Now we let them set up.

Durango rounhouse construction.

In 15-20 minutes the castings are hard enough to remove from the molds.

Durango rounhouse construction.

The castings are gently removed from the molds.

Durango rounhouse construction.

The molds are rinsed off and the process can start one again.

Durango rounhouse construction.

All that HO scale stuff looks so small! Where the heck am I going to stack the new castings? Somethings got to give.

Durango rounhouse construction.

The casting sink corner.






    Next section:     The Floor Plan    



    Limited Run - O Scale    

    Future Kits - O Scale    

    Scratch-Building Stock Panels   


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