Stamp Mill in O Gauge

Stamp Mill in O Gauge

After several years of having an empty space on my layout, intended for a stamp mill, I decided it was time to build it.  I purchased a basic set of plans from Western Scale Models.  These structures don't have to be large as fewer stamps can be used and a variety of building sizes are possible; stamps come in batteries of 5.  However, I decided 20 stamps would be more impressive.  I wanted to include all the interior machinery and equipment, not just an exterior structure.  This would require the roof to open for viewing as well.  The following is not intended as a step by step guide to building one, but an insight into elements that can be applied to any structure such as building board-by-board siding, board and batten, and so on.  Some of the weathering techniques have already been discussed in my other articles, so visit those as well.   

This image is similar to the stamp mill I am building, approximately 21" x 21" x 20" high.  The cut-away shows the basic elements from delivery to processing.

  Processing...

 The process of treating gold ore to extract gold (and silver) and, therefore, produce bullion is called milling. The building housing the process is called a stamp mill. A stamp mill is similar to a mortar and pestle. Indeed, the vessel holding the ore being crushed is called a mortar. In order to extract the gold, the gold ore was first brought to the surface of a mine, then crushed in a massive stamping mill first by a rock crusher then by repeatedly dropping heavy stamps on the ore in the mortar. To mechanize the repeated lifting and dropping of the stamps, a rotating cam typically engages a tappet on the stem of each stamp. A battery of stamps dropping in a single mortar can all be lifted by cams arranged along a single shaft. While the rocks are fed under the stamps and being stamped, water was being mixed in and the slurry fed onto Wilfley tables. The Wilfley concentrating table came into use in the late 1890's. The table is made of wood covered with linoleum. The mechanism below shakes the table and causes the separation of the quartz tailings into the "tailings" side of the table and the heavier materials into the "concentrate" end of the table. The last step was to send it to the local bank.

  The Exterior Structure

 Base

Since this will be a fairly large structure with interiors, it will be heavy requiring a very firm base, so I made one using 3/4" MDF with two basic levels.  This will enable me to carry it as required and eventually set it into place securely.

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 Scale Lumber

I estimated the lumber I would require, using the mock-up, and purchased the strip wood from Mt. Albert Scale Lumber Co.  This was followed by applying grain to each piece using a file card, dipping them into a solution of Sweet and Sour, followed by drying in the oven at 200 degrees for an hour.  These were then laid out and sorted according to size.  This light stain would be fine for interior unweathered wood.  The exterior sides would later receive another coat of darker stain.