Easy CNC conversion of a small mill by fred27 Download My first Instructable made use of a small CNC milling machine. I've found this machine really useful so I thought I'd document getting it up and running. You may read this Instructable and think "Well, he just bought a few thing on eBay and plugged them together" and you'd be right. This isn't a complicated build of a whole custom designed machine. It's a good way to get up and running quickly and at a reasonable cost. I'll explain why I chose the machine I did and what some other options are. I'll explain the pros and cons of my build. Read on, and you could be "making chips" in no time... Finding Your Adventure in Montana When you’re in Big Sky Country, you can fit a lot of adventure in before dinner. Ad By Montana Step 1: Other options Why not a 3D printer? I think a lot more people have 3D printers than CNC mills and they're great tools. There's a bit of an overlap with a mill, but they both have their strengths and weaknesses. Comparing a mill to a printer we broadly have: Pros Cons You can mill PCBs. This is one of the main reasons for my choice. I was about to go down the laminator / toner transfer method of PCB manufacturing when I discover the milling option. You can mill different materials. Most 3D printers are limited to one or two plastic materials. I can use anything softer than steel - usually wood, acrylic and aluminium in my case. It can be messy. I spend a lot of time vacuuming up sawdust or ground up bits of plastic or metal. Rounded internal corners As you're cutting away material with a milling bit you're limited by the radius of your milling bit when doing internal corners. External corners can be perfectly square and sharp, but not inside. There's also differences that can't really be described as a pro or con - just whether they suit what you're doing. With a mill you're subtracting material; with a printer you're adding material. If you want a large block with small cutaways then a mill is the best tool for the job. If you're making a single-piece hollow shape then a printer would be better. Why not a laser cutter? Laser cutters are expensive and I haven't seen any simple home builds. They're great for accurately cutting through soft sheet material like wood and plastics but can't do PCBs for instance. Basically they're a also a good tool, but not what I wanted.