Homebuilt CNC Routers

If cutting wood, plastics, and composites is your goal, then a CNC router is going to be your tool of choice. The only real limitation on a CNC router is the physical size of the machine.

If you’re interested in cutting large signs, plaques or other parts, then you might want a machine that has a cutting area of 4 feet by 4 feet… or even larger. A great big machine isn’t that much more expensive than a smaller one. You might want to double up on the number of stepper motors, and the size of those stepper motors, but that won’t add a lot of cost to the project. The downside of having a large machine is that it’s LARGE. Your wife probably won’t let you put a 4 foot by 8 foot machine in the corner of the game room…. and it can take up a significant part of even a large home workshop.

If something small, like printed circuit boards, is all you’re concerned with cutting, then a little 12 inch square CNC router will certainly do the job. Most all CNC routers use either a conventional, hand held woodworking router manufactured by companies like Hitachi, Bosch, DeWalt or Porter Cable. If you’re building a smaller machine, you can use one of the smaller 1/4″ collet “Trim Routers” that are intended for flush trimming laminate counter top material like Formica. And if you’re doing truly miniature work, you can use a hand grinder like a Dremel tool in your mini-CNC router. The decision for the size of the router is based on the amount of material that you want to be able to remove… and the availability of suitable diameter router bits and collets to hold them. Turning an .018″ diameter router bit with a 3 horsepower router is possible (I’ve done it !) but it requires an awkward combination of reduction collets to do it. Turning a half inch diameter, ball end bit with a Dremel tool is…. Impossible.

CNC Routers are the most commonly “home made” machines. With ingenuity, and hardware store components, you can build a very successful CNC router. Mills and lathes are often converted to CNC usage, but rarely built from scratch. They require massive steel castings, and lots of machined components that just don’t lend themselves to being built in a home workshop.CNC Routers are generally either a moving gantry type design, or a moving table type design. The moving gantry machines require less space, since the table isn’t moving out beyond the basic footprint of the machine, but the moving table machines can often be built more rigidly, since the fixed gantry can literally be built like a bridge, since it doesn’t have to move.