What's all this I hear about CNC machines? What are they? Lathes? Mills? Smithys? It sounds as if you can tell them how to make gun part, throw them some appropriately size bar stock, and they throw you back a gun. It also sounds as if you can punch a button and they machine will start throwing left handed guns at you. I'm sure this is all an oversimplification, but what kind of setup would be needed to make receivers for Mausers? 1911's? Are we talking about hundreds of thousands of dollars or millions?

H. C.

Henry,
That is somewhat oversimplified but basically correct. You feed instructions to the computer and put material into the lathe, mill, grinder, saw and it will perform whatever task it is programmed to do. They cost anywhere from many thousands to a few million depending on the machine and the task required.
Jim

CNC is short for Computer Numeric Control. This means that whatever piece of machining equipment, mill, lathe, or whatever has its movements controlled by a computer or more specifically a computer program. The computer program tells the machine exactly what to do and what tool to use and also changes tools during the cycle. CNC allows for more precision and repeatabilty in manufacturing as well as keeping costs down.

ZM

Henry,
You also need to know how to program it and you would need to build fixtures to hold your parts. Muliple axis machines allow you to have several parts on a rotation and allows you to do multiple tasks with tool heads that change on command.

You can see a CNC at the following site of Mark Strattons under Shop Tour. Mark uses the mill to turn out swamped octagon barrels. They have a curve incorporated in the taper of the octagon.

http://www.gunmaker.net

CNC machines may be mills, lathes, or a combination of the two. As previously mentioned the letters stand for "computer numerically controlled". The computer controls allow for repeatability of complex shapes and allow for the machining of shape in ways that would otherwise be difficult or impossible. They are not perfect. A worn machine still produces faulty work. Improper setup still produces faulty work. It is possible to produce this faulty work with great rapidity however.
When someone like me tries to program one it is possible to do an amazing amount of damage to tools and workpieces. In generak I can produce a fairly complex piece with a chisel and files in the time it would take me to program it! I'm really impressed with the way the good operators can program stuff and have it work. They use guys like me to dream up and make jigs and fixtures and in truth guys like me will soon be obsolete I reckon! Regards, Bill.

http://www.haascnc.com/

[ 09-08-2002, 21:48: Message edited by: Curtis_Lemay ]

The real key to running CNC equipment, especially mills, is the fixturing. It is what truely separates the men from the boys. Typically, most CNC mills and lathes can hold tolerances of plus or minus .0002", but, it is the method that you use to hold onto the part, or the sequence in which it is done, that will determine whether or not you can obtain those tolerances on your parts.