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Saturday, July 27, 2013

Cripple Creek NGRR Part One: A look at gold mines


Micro layouts take up very little space, and even though this 1:1 scale train is operating outdoors, and in the real world, it is tiny compared to similar lines.  The Cripple Creek and Victor is a 2ft gauge line that only has about a 3 mile main line.  It has one station at Cripple Creek, and has a two track yard with a spur for servicing.  However, operations are tricky as two trains run at once!  The key in the design were two wye's, one on each end of the line.  In case you don't know, a wye for a train is like a three point turn for a car.
The train pulls ahead along track one and clears the switch.  Then the train reverses and backs through the second leg along track two.  Finally, the train pulls ahead and continues along track three in the opposite direction from which it came.

With operations of a pair of wye's, a very tight yard, and very little spare trackage, the moves must be planned carefully, especially when two trains are meeting in the yard, one outbound, and the other inbound.  There is also a third locomotive in running condition as a spare.  All in all, this line requires a different concept than the larger lines.  Essentially, a micro layout concept is embedded into the line's function and operation.


Cripple Creek and Victor sit at over 9,000 feet, and getting a train that high up is no easy task.  So why are there trains this far up in the air?  Well, it all started with one man.  Bob Womack discovered gold in the sleepy little community of Victor in 1890.  Although the railroad was nearby, the Colorado and Midland hadn't exactly made an effort to put in large amounts of track.  With the discovery of gold however, a boom happened to the area.  Miners came from all around to stake claims in an attempt to strike it rich.  Hoist towers went up all over the place between Cripple Creek and Victor  shaft mines were dug, and gold began rising from the depths of the earth by the ton.  The Midland as well as several other railroads entered a race to see who'd gather the most mines under their influence.  The reason this is focusing on the Midland is because the railroad is still in use as the CCVNGRR, however it was standard gauge (4' 8.5") while the tourist line is narrow gauge (2ft).  By 1900, the Midland as well as several other lines had linked both Cripple Creek and Victor, plus all of the mines, to the rest of the world.

So this is why Cripple Creek became a real town.  However the operations of the railroad relate to the industry.  So one must ask themselves, how does a gold mine really operate?  So let us drift from trains for a bit while we discuss what goes on inside and around a gold mine.


True, no one really needs so much detail, but a basic understanding of how an industry works helps people visualize how the railroad played it's part.  With gold mining, equipment, men, animals, food, supplies, and materials were shipped in by train.  Gold was then mined, brought to the surface, crushed, sorted, and dumped.  If a mine was large enough, gold may even be extracted from the ore on sight.  Basically, gold was shipped pure, or in ore form on trains.  Before we get ahead of ourselves, let's go back to the first steps and see how the gold was mined and processed.  Then we'll look at loading and shipping gold.

Gold Mines: different methods

Gold Mining can take several forms, placer, shaft, open pit, and dredging.  Placer mines are usually very small operations creek side looking for small nuggets or filings that may have washed downstream from a vein with water running through it. If a placer mine is successful, a sluice box would be constructed where gold ore is run through a long channel with water carrying the sediment down the channel. The box has wooden ribs spaced so that the gold nuggets sink and are trapped while the non gold rock is washed away.  Open pit mines are the type that one sees today, where tons of rock are removed from the mountain side and shipped to a refining plant to have the gold removed.  This system has come under fire for being destructive to the environment.  But in mines' defense, they are supposed to replenish the land by planting trees, shrubs, and flowering plants to keep the soil from washing away.

Dredging is used when in a high water area.  The dredge picks up sediment from the bottom of the river, and then processes out the gold ore.  The sediment is then dumped back into the river.  What we'll look at in detail is shaft mining.  Shaft mining consists of a network of tunnels where miners pick through the rock and haul out what may be carrying gold.  The other sediment which is rough up is simply dumped in a tailing pile.  Originally, carts were pushed by hand, or mules towed the out from the shafts.  With the invention of steam however, locomotives did this job.  To keep from smoke building up in the tunnels, compressed air, non-fire steam, and eventually electric locomotives did the underground work.  Various other cars (which we'll get to) were built and several types of dump cars stand out.  Fortunately for modelers,  many unique pieces of mining equipment survive today in various places.

Gold Mines: a look at shaft mines

Unfortunately, many old and abandoned shaft mines are not available for exploring by the public.  This may be  good since mines were, still are, and always will be a dangerous place to be.  What we can take a look at however is what's on the surface.  Look below to see several photos of a mine at the surface:

First, we'll go through the parts of the shaft mine and will later get into the process of mining gold.
The hoist wheel is a symbol of the western mines.  The wheel was the main support for the elevator shaft, with the wire running around the top of the wheel and down the backside of the mine to the elevator house.  

The hoist tower was essentially the top of the elevator.  The tower allowed buckets of ore to rise above the hopper and be dumped.  Sometimes the same tower would be used to carry miners into the depths of the mine.

 Above is the hopper, this is where the ore is stored until it can be sorted and processed. From here, the ore can go several places
 Smaller nuggets may end up in this secondary hopper below the primary.  This hopper would feed directly into the barrel separator (discussed later).

 Larger nuggets may go directly to the train in this particular mine, but in large mines chemical sorting would be done on site.  With this mine, it appears as though larger rocks were immediately loaded into waiting rail cars, while smaller nuggets would be separated according to size.
 A chute from the secondary hopper would lead into the sorting house as I call it.  This is where the nuggets would be separated according to size.

 Here we can see the full structure.  This mine is somewhat large, with a hoist tower easily over 40ft in height.  If one could imagine spurs leading to the mine where cars would be loaded, this scene would look much busier.  Although the tracks are gone and miner no longer work in the mine, we are fortunate to have an example of a mine still standing.  Also, I missed the metal shed, this shed appeared to be the shaft house and machine shed.  a large coil of wire would be attached to a steam engine and several gear systems.  This wold be where the elevator was operated from.  a small crew should keep the elevator going up an down all day.  Also miners would enter and exit the mine through this shaft and often used the elevator.  If a mine had two shafts, one might be for crew and the other might be for ore, otherwise both used the same hoist.

So now that all of the parts have been pointed out, here is a diagram of the completed mine:

  1. Hoist tower 
  2. Hoist tower wheel
  3. Elevator house
  4. Hopper
  5. Secondary hopper
Gold Mines: the sorting process

After gold ore was brought up, it was usually sorted on site.  Below is a sorting barrel diagram.  The barrel would be powered by a stationary steam engine and rotate the barrel.  The ore would move down the barrel with smaller chunks falling through the perforated barrel wall. Finally, the larger chunks and nuggets would fall through the end screen and onto a conveyor belt. Once on the conveyor belt, miners would pick through the rock, trying to find ones that still had gold in them.  All of these chunks, now sorted by size, would be held in a track side hopper until the train came to load their cars full of the gold.  The gold would then be taken by train to a processing plant where the gold was extracted from the ore and sent into the global market.  Below is a diagram of the barrel:

  1. Ore enters and smallest nuggets fall through.  These are called "fines".
  2. The belt drives both the barrel and the conveyor belt
  3. The "mids" screen where mid-sized nuggets would fall through.
  4. The "clutches" screen where larger nuggets fall through.
  5. The "slimes" screen where the largest chunks would fall onto the conveyor to be sorted, broken, and then sent into the track-side hopper.
Alternately, some mines used a stamp mill to grind and crush the ore until it was a uniform and small size.  This produced a one size gold ore instead of several different grades.  Below is the stamp mill diagram:

  1. The hopper where pre processed ore is stored
  2. The belt drive which turns a cam crank.  This cam raises and lowers large crushing pillars of iron.  The blows smash and break the rock into  uniform size.
  3. The wooden frame keeps the cam and the pillars aligned correctly and operating efficiently.
  4. The bin where the final processed ore is stored and then shipped.
So now readers have a basic understanding of how a mine works.  The next step is to explain how the railroads played a part in gold mining and then we can get into the equipment mining railroads used to extract and transport gold from mine to plant.  Finally, we can get into how the Cripple Creek is related.  So tune in for part 2 of 3 in this lengthy post about Cripple Creek.

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