Manufactory – CNC Router Table

Well, there it is. An actual functioning CNC router table.

Being one to invent random words, I came up with “manufatory”, to mean “manufacturing at the speed of thought. What am I trying to get at? In general, I’m on a crusade for tequity, having an equity share in technology, for intergenerational wealth creation. Whether it be owning stocks in a company, or patents, or other artifacts, being able to ride the rising tide of tech wealth requires owning a piece of it, and not just being a consumer of tech.

So, what’s this manufactory business about? Software production is one kind of intellectual property, but not all things are software. Everything we interact with in the world was created by someone, or some machine, somewhere in the world. Being able to think up a design, produce the goods economically, and sell them into open markets, is tequity.

A couple blogs back (Embodied AI – Software seeking hardware) I mentioned three machines,

• 3D printer
• CNC router
• Robot arm

There are myriad machines that are used to manufacture goods of all kinds. I am choosing to focus on these three forms because they are immediately approachable, relatively inexpensive, easy to build, and can be used to both create immediately useful and sellable goods, as well as create the parts necessary to build more and different machines.

The machine I built is the Lowrider CNC 3, by V1 Engineering. This machine is very simple, primarily able to cut sheet goods, with an emphasis on full sheets (8’x4′) of plywood, MDF, and the like. This is NOT the machine you’re going to use to cut an engine block out of a billet of aluminum. There are many ways to get started on this one. There are a number of parts that are 3D printed. It also uses ‘rails’, which are nothing more than tubing you can buy at any hardware store (electrical conduit tubing). There are bits and bobs of hardware (screws, nuts, bolts, timing belts, motors, electrical board, linear rails) which you can source yourself, or you can just buy the hardware kit, for $306 USD. For this first one, I purchased the hardware kit, and printed all the necessary parts myself. Save a little money on printing, at the expense of spending a fair amount of time doing it. After gaining experience with the first one, I’ve embarked on building a second one.

Same machine, sample printed parts, this time in PETG instead of PLA for some of them. I’d say the printed parts cost roughly $50 in plastic, and a couple days of printing, depending on what kind of machine you have. Mostly I print on my prusa mini+, because it’s relatively fast. The larger part I had to print on the larger Prusa MK3, because it is too big for the mini.

Once you’ve got all your printed parts, and hardware kit, you’re ready to assemble. The instructions are very easy, and step by step. You don’t need really fancy tools. A screwdriver, couple of socket wrenches, and that’s about it. Following the instructions, I was able to assemble in about 3 days of casual time. This could easily go together within a few hours in a single day, assuming you’re well organized with your tools and a nice workspace.

Alright then, you’ve got a basic machine. Next up are the electronics.

This is the jackpot board. It was designed specifically to be a low cost brain for various kinds of CNC machines. In this case, we’re doing a large format CNC router table, but it can also run a laser cutter, or any kind of machine with up to six motors. It’s all you need when you’ve got small motors (up to nema 17 realistically). It has the motor drivers onboard, and a ESP 32 compute module is the heart of its intelligence.

The board is running a firmware called fluidnc. Fluidnc does two things on this board. The first is, it takes a machine description file, and uses that to understand how to move the motors based on various commands. The second is, it interprets the CNC commands that are your design, and generates the appropriate movements based on those commands “cut this arc, move this much in that direction, lift the cutter…”.

Another thing this board does is support a web interface.

This web interface is enough to get you going. You can upload your design to be cut, over the network, press the button to start, and away it goes.

The ESP32 compute module is doing a pretty heavy lift here. It’s running the brains of the machine, sending movement commands to the motors, plus putting up a web interface, plus responding to commands from that interface. All of that from a compute module that costs about $10!! That’s what I call a true computicle!

OK, this is all great. I can build a machine rather quickly, and inexpensively. It has a brain, and it can cut stuff. Now what?

Well, I’m a software guy, so all of this is ultimately in service to a software solution right? I want to put “AI” to use. Ideally, I’d be able to articulate some design, working with something like ChatGPT, and send that design to the machine to be manufactured. To that end, I’ve started creating my own GPT (powered by ChatGPT).

I’ve been training CNC Buddy for a while now. I’ve told it about fluidnc, how you create a configuration file, what gcodes it supports, etc. I’ve gone back and forth, telling it the challenges I had while building my machine, and how I overcame them. CNC Buddy, being a “GPT” knows language stuff. You could actually ask it to help you generate a gcode file, if you’re really good at prompt engineering. More than likely though it will point you at a CAD/CAM program for that.

I find CNC Buddy to be most useful in answering questions I might typically post in a build forum, or asking some experienced person. This is great for classroom environments, as the collective can enhance the knowledge base of CNC Buddy with new experiences, making it better at answering questions in the future.

So, that’s where we are today. The basic machine is done, and capable of doing some cuts.

Where do we go from here? Well, after the excitement of “just get it running”, I will now go back and clean up this machine. The wiring can be tidied up mostly, and I need to make some improvements to the table this sits on. In the meanwhile, I will build another one, pretty much the same as this one, but for a larger full sized table.

The beauty and benefit of this large format gantry CNC is that other things can be done. I’m not going to try and cut metal with this, although it can cut aluminum. I’m going to do things like mount a laser diode, and possibly a 3D printing head. Then the machine becomes more than it was intended for. This is a base platform for enabling all sorts of automated tasks, where having a tool of some sort mounted to a low gantry is useful. I will also be looking at fluidnc, with an eye towards making it smaller, and simpler. It’s great that it hosts a web site as part of its duties, but I don’t actually want that UI running there, so alternatives.

At any rate, this is the first of the 3 machines we’re currently building. If we want to manufacture at the speed of thought, we need to start with being able to affordably build machines that give us manufacturing capabilities, so here we are.

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