Becoming a professional CNC milling machine operator requires learning at least a little about a lot of things. Actually, it’s more like learning a lot about a lot of things – from CNC programming to cutting parts with extremely narrow tolerances.
Once beginners have learned some of the basics in each of those areas, however, they’re often eager to jump into some projects. To help you get started, we’ve assembled a shortlist of some of the best CNC milling projects for beginning machinists.
To start, create an entire sheep with your CNC milling machine! Actually, this is a far simpler project than it sounds. You’ll create a CNC program to carve out the outline of a sheep in a piece of material. Any material will do – it’s probably best to start with something other than high-quality steel. The project helps reinforce your basic programming skills, as well as help you learn where to start and finish your CNC program. And you can adjust the basic program – available here – as needed, in order to accommodate different machines, materials, and tool sizes.
A well-executed Turner’s Cube looks like even more of an engineering marvel than it actually is, with layer after layer of geometric shapes within the cube. That’s not to say that it’s an easy project – making a good Turner’s Cube will test your ability to keep the cube itself perfectly square. You’ll also need to ensure a perfect finish and an evenly-proportioned interior. But when done correctly, you’ll have passed your first CNC milling test – and gained an impressive ornament for your desk. Find some more examples and instructions from Mark Thomas and CNC Cookbook.
At some point in your milling career, you’ll need to create a through-hole in a workpiece. The problem is that the only thing beneath your workpiece is the bed of your mill, so when you drill your hole you’re likely to either damage your bench or (more likely) ruin your bit.
Soft parallels are a simple, cheap, and easy way to solve all of that. You can find a great set of instructions here, but the short version is this: first, use a softer metal such as aluminum so that if you ever do damage one of these, you won’t harm your tools. After that, your challenge is simply to make these parallels, well, parallel, so that you can use two or more of them to support a workpiece and give yourself some much-needed elevation.
Conceptually, this is one of the easiest projects on the list, but you can still use it to practice your precision cutting. Once you’ve finished, you’ll find that it’s easily one of the most useful tools to have around the shop.
A tap guide is simply a block of metal with preset holes drilled through it. You can use it to “guide” your drill into a workpiece when cutting a new part, hence the name. Milling your own tap guide forces you to practice precision cutting, tapers, and the measuring skills necessary to match each hole to the apex of the “V” cut into the bottom of the block.
Order of operations, grind allowance, job planning – that’s what you’ll learn while making a toolmaker’s vice on your milling machine. It’s a fairly challenging job, although the challenge comes more in the planning than in actually cutting the parts. Regardless, it will push your development forward as a full-fledged milling machine operator. And give you a handy tool, to boot!
Here’s a project that combines a number of techniques. You’ll need millwork and lathe work, you’ll need to master threading and slot cutting. And this micrometer stand project also provides several opportunities to make it look nice. You can practice your finishes until they shine, and at the end you’ll have a project that is beautiful as well as immensely practical.
Machinist’s hammers are often designed to be a beginning lathe project, but with a little modification, you’ll find that they work equally well on the milling machine also. Of course, if you have a CNC lathe in the shop, make this a project for both machines and push yourself a bit further.
The basic 123 Block is a more elaborate version of the soft parallels mentioned earlier. Like the parallels, they’re not difficult to make, but they do require some precision. The key is to keep each block the exact same size and shape as the others, ensuring parallel and matching sides. You can use 123 blocks to support parts or to keep them elevated off the mill bed, allowing operations to be milled completely through the workpiece.
123 SuperBlocks take the idea a step further, using an alternating pattern of counterbored threaded holes to allow the blocks to be joined together. Keeping the alternating pattern absolutely precise will test your early machining skills, but also force him to learn how to execute a simple project to perfection.
You can find a detailed outline of the plans for the 123 SuperBlocks here.
Each of the tools listed above will push your development as a machinist, forcing you to learn slightly different techniques and think about each project in a new way. Whichever project you choose, you’ll be a better machinist after you’ve done it.