- [Kevin] Oh, (beep).
If you're on the fence about
getting a CNC router,
then this is the video for you.
Let's take a look at the core workflow
used to run a hobbyist CNC router.
This video will focus on three-axis CNC routers,
which are the most popular among hobbyists.
This includes the LongMill, Shapeoko, and X-Carve
to name a few.
Notice they all have three axes.
The X, Y, and Z.
The basic workflow required to run these
can be broken down into three main sections.
First, you come up with a really clever
design on the computer.
Second, you take the design
and create instructions that describe how to carve it.
This process is called CAM,
more on that later.
Third, we need to hand these instructions
over to the machine.
This is usually done with a digital interface.
We can then hit the start button
and the machine will cut out the design.
Of course, each of the three sections
has many different subsets.
Let's take a deeper dive into each section.
The first step of the process
is often referred to as CAD,
that stands for Computer-Aided Design.
It simply means we're using computer software
to create the design.
This is where most beginners start to sweat.
But I promise you,
it's not as hard as it seems.
For starter projects,
you can use simple 2D graphic programs
like Inkscape or Illustrator.
The other end of the spectrum
is professional-level CAD programs
like SolidWorks or Fusion 360.
In between, are programs created specifically
for hobbyists CNC machines
like CAMLab, Carbide Create, and Easel.
Which software you choose will also depend on
the type of cut you're trying to create.
Most CNC projects use one of three
different cutting strategies.
First, we have 2D cuts.
These are when we simply have the machine
trace an object and cut it out.
Things like letters and basic shapes.
Second, we have the three dimensional cuts,
where the machine is using
all three axes at the same time.
This method is used for more complex projects.
In between these two, we have 2.5D.
This is when we're just following
simple shapes like regular 2D cuts,
but we tell the machine to cut deeper in a certain area.
It's not a true 3D cut
because the Z-axis never moves
at the same time as the Y or X-axis.
I went ahead and sketched out
the ice cream emoji in Fusion 360.
I could technically leave this as a 2D sketch,
but I'll turn it into a 3D body
so it's easier to see what we're cutting.
Comment below which of the three cutting strategies
you think this design requires.
Once we've created the design,
we need to create the instructions for the machine.
This second step uses CAM,
or Computer-Aided Manufacturing.
That means we're using a computer
to control a machine that can manufacture things.
Remember, CAD is design
and CAM is manufacturing.
Fusion 360 is my personal software choice
because it does CAD and CAM
in the same piece of software.
It's also free for hobbyists to use.
You can also learn Fusion 360
right here on my YouTube channel.
The first step when creating our CAM instructions
is to define our material.
I'm going to cut the ice cream emoji
out of some scrap wood,
so I'll enter the dimensions in Fusion 360.
Second, we need to choose our cutting tool.
Cutting tools will have to be a separate video,
but the number one takeaway
is that our cutting tool
must be smaller than the objects we want to cut.
A 1/4 inch end mill physically
can't drill an 1/8 inch hole.
So we need to tell the software
which tool we're using
to make sure it will work with our shape.
We can also define the speeds and feeds.
This concept is one that often intimidates newbies,
but it's much simpler than most think.
The cutting speed is defined as
how fast the cutting tool moves
in relation to the material.
You can think of this as the speed limit.
The feed rate is defined as
the distance the tool travels
during one revolution of the tool.
Most hobbyist projects are for common materials
like MDF, plywood, or hardwoods.
Thus, we can simply copy and paste
the ideal numbers from online cheat sheets.
You don't need a Math or Engineering Degree.
These cheat sheets are a great starting point
when you're just getting started,
and you'll eventually learn
which speeds and feeds work best for you.
Once our material and bit info is defined,
we need to write the body of the instructions.
This is where we tell the software
what shapes to cut out.
We refer to these as the toolpaths,
or the path through space
that our cutting tool follows.
How you achieve this will differ
from software to software.
But as you can see,
this is pretty easy in Fusion 360.
I've set up one toolpath for the inner design
and a 2D contour toolpath for the outer shape.
The biggest advantage of CAM software
is that we can simulate our cut
before sending it to the machine.
This helps us catch any potential problems
before we plow through our material
or, even worse, break the machine.
Beginners often get frustrated
when the machine doesn't follow the instructions.
But the problem lies in the fact
that the machine follows all the instructions.
When something goes wrong,
it's because we told it an instruction
that we didn't mean to.
We're done creating our instructions
once our setup and toolpaths are complete.
At this point,
we need to hand them over to the machine.
Right now the instructions are on our computer
and the machine doesn't know about them.
To get the instructions to the machine,
we'll need to export them in a language
that the machine can understand.
Most machines read something called G-code.
The "G" stands for Geometric.
The great thing about G-code
is that you don't ever have to learn how to write it
as the software does it all for us.
However, as you get more into the world of CNC machines,
you'll find having a basic understanding of G-code
will help you avoid unwanted problems.
Put simply, G-code is written out
to tell the machine where to travel to.
Remember our machine has three axes.
For now, let's forget about the up and down Z-axis.
Our machine now only moves in the X and Y direction.
This is similar to a graph
where points are plotted on a Cartesian plane.
The G-code includes lines of code
that plot each shape of the design.
Remember our toolpaths?
They dictate what the software includes in the G-code.
Now, there's a little bit more to it than that,
but hopefully that gives you
a basic idea of what's going on.
Once we have our G-code,
we have to find a way to get it to the machine.
Hobbyists machines often have a control box
that includes a microcontroller,
such as an Arduino.
That means we'll need to use our computer
to communicate with it.
Depending on the machine,
this can be done straight
from Fusion 360 using a plugin,
or we can use GRBL,
which is an open-source CNC controller.
This lets us open the G-code
that was generated by our CAM software.
First, we need to strap in our material.
We can simply screw in the material,
strap it in place with clamps,
use double-sided tape
or a vacuum table that sucks the material down.
We also need to place the appropriate bit in the collet.
Remember this has to be the same
as what we defined in the CAM software.
Next, we need to place the machine
in its starting position.
With most hobbyist machines,
we'll have to do this manually.
Most hobbyist machines also require us
to manually adjust the speed of the router
and turn it on.
We can then simply hit the run or play button,
and the machine starts to cut.
Cross our fingers that our instructions
only include what we want.
Remember, if the machine travels
where we don't want it to,
then it's because we told it to do something
that we shouldn't have.
Most errors are caused
by including features or settings
without knowing it.
Thanks for sticking around
to the end of this video.
You can help me out by hitting
that like button for me.
And let's see if we can get this
to 5,000 likes in the first week.
If you're ready to dive into the world of CNC machines,
then be sure to subscribe.
I've got lots of Fusion 360 CAM tutorials
and CNC projects coming soon.
If you're ready to learn Fusion 360,
then click that playlist
in the lower right-hand corner.