Author (yesmama). Submitted on Fri, 25 May 2012
Building your own rock crusher really isn't that difficult, but you'll likely need a welder to do it. First, I will discuss several different types of small scale rock crushers, and how they work. One common primitive rock crusher is the arrastra, a device which has been used by miners for centuries. An arrastra is a rock lined pit that is dug out around a whim. A horse, mule or donkey is hitched to the whim and a large boulder is drug around the pit in a circle. Rich ores are added to the pit and they are crushed as the large boulder is drug over the gold ore. Water is used to wash the crushed ore out of the pit once it has been reduced to a small size. It's a very slow process, and too large, and too much work for the average prospector to consider.
The basic concept of rock breaking is making big rock pieces into little ones. Popular hand crushing systems include the hand stamp type hammer crusher. Usually these are fully hand operated like mortar and pestle systems, but more elaborate spring type designs can also be made.
The following sketch shows a simple and cheap means of working in a small way, a rich quartz lode, which carries coarse gold freely. It is known as a 'Dolly,' and two men with this device, will crush enough ore each week, to give a very satisfactory 'clean up' by Sunday. This is the type of rich gold quartz ore with visible pieces of free gold that one might find while out prospecting with a metal detector.rotary kiln:http://www.hx-china.com/19.html
No matter which crushing system you're using, the process will go far faster, and come out better if you do repeated screenings of the material from time to time. What happens in crushing is that some of the material gets crushed down to the size you want but other pieces don't. The small stuff then often gets in the way of the crushing process as you are working, basically protecting the larger pieces from being crushed and creating more work. To speed things up and make things work properly you need to screen out the stuff that's already been crushed to a small size. So as you are crushing, stop and screen your material, removing any free gold which has already separated from the rock during your crushing that won't go through your screen with your fingers. The coarser rock that won't go through your screen can then be returned to the crusher for further work to break it down, and the fines won't get in the way.
Making your own hand crusher can be done with a welder. You need a heavy base, a heavy large pipe that is the outer container. These two pieces form basically a container that holds the rock being crushed. You also need a heavy cylinder that forms the stamp 'shoe' the piece that rises and falls, the part that actually does the breaking of the rock. Think of this piece and the hammer that pounds the rock. The last piece is the rod which is attached to the shoe, this is the part that is lifted to raise up the shoe. This piece is basically the handle used to lift the hammer up.
The last piece is the rod which is attached to the shoe, this is the part that is lifted to raise up the shoe. This piece is basically the handle used to lift the hammer up.