Servo - March 2012

CNC Build 4

CNC Build 5

The KRMx01 CNC (shown in Figure 5) is made from steel and aluminum. It has a cutting area of 43” x 32” in order to build larger projects. The new design of the KRMx01 also includes a lower gantry design for rigidity.

In addition to simplifying the overall design for the book I was writing, I added a few features that were part of the wish list I kept in my head while working with my previous CNC designs. As shown in Figure 6, these included particleboard shelves, an MDF T-Slot clamp table, an air exchanger, a dust shroud, and an E-chain for cable management.

This machine was a dream. I used it to construct parts for many projects, and even though I have built other machines since this model, it is still in operation. The step-by-step book based on the KRMx01 CNC took nearly six months to complete, but it was well worth the effort.

You can see Build 4 in action on You Tube at

www.youtube.com/watch?v=GR_nihzmlgI.

FIGURE 5.

While I considered the KRMx01 a success, a true DIY CNC builder never stops looking for ways to improve the process. We are also always looking for an excuse to build the next machine. As with many things, it isn’t just about the destination. It’s about the journey.

In early January 2012, I was asked to demonstrate my KRMx01 CNC at the Washington DC Science and Engineering fair in late April. Doing so brought some problems to the forefront. The machine wasn’t designed to be transported, so it was too large to fit through my shop door. In addition, the design was not conducive to dismantling and reassembling. What to do? Design a new machine! And thus, the KRMx02 CNC was born.

While designing this new CNC machine, I wanted to incorporate the following features: • Easy to build design adaptable for various size machines.

The KRMx02 (shown in Figure 1 at the beginning of this article) fits the bill. It has a 30” x 27” cutting area and sports a full aluminum clamp table.

CNC Basics

Now that you know my history, I want to show you some of the robot related items I have built with my CNC machines. Before proceeding, let’s review some CNC basics. This will give you a head start if you decide to build your own CNC.

CNC stands for Computer Numerical Control. It is a process where a computer is used to automate the machining process. There are numerous CNC style machines, but the one I am about to explain is a basic CNC mill, or router, in my case.