This section covers things like checking the stepper motor zero position, actual machining, the Z probe, home switches, and other topics in more detail.
Checking the stepper motor zero position
It might be a good idea to make some pointers and to draw a line on the hand wheel with a permanent marker.
To make things a bit easier to understand, have a look at the clip below:
I made my pointers from aluminium, but I started out with thick paper.
If your steppers look like mine, regardless of your machine type, and you're having trouble with cutting round circles (i.e they're coming out oval) or maybe some other annoying problem,
try using "My Mach 3 set-up" from the top menu bar
Starting your machining
First thing to mention here is safety, I know it's boring, but don't ignore it!
DO NOT WEAR TIES OR LOOSE CLOTHING WHEN OPERATING YOUR MACHINE
KEEP YOUR FINGERS WELL AWAY WHEN THE CUTTER IS ROTATING
WEAR SAFETY GLASSES
Below are some videos of my machine cutting MDF.
You can hear in the first video the extractor I made, using a household vacuum cleaner.
In the second video, take a closer look at the machine bed.
I made this bed because I was not very happy with the one supplied with my machine. It is made from 16mm steel plate and ground on both sides, with rows of holes drilled and taped M6 for the clamps.
The usual thing to do when cutting right through the work is to put a piece of board down on the bed of the machine. Then, on top of that, your work so that you don't machine into the bed. This board is often called a spoil board. Spoil boards can be clamped to the bed, and machined to produce a true flat surface so that your work piece will come out flat and square.
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Spoil board with some clamps and an aluminium square to represent the work piece.
Please note that these clips are for demonstration.
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The Z probe.
When set up in Mach 3, the Z probe is useful for setting the cutter to zero on top of your work piece. The set up and how to install it is found on the "my mach 3 settings" menu tab. See also the clip below of the probe in action:
Home Switches.
These tell the machine where it is, a reference point, and also provide a position to park the X, Y, and Z axis, usually in one corner of the bed. See the clip below of the Y axis running on to its home switch:
1 2
My home switches are connected up to be normally closed.
So what does that mean?
In figure 2, the switch is normally closed, which means the current (5v) on my machine, flows right through the switch to ground. When the machine axis runs on to the switch, it breaks the circuit, and the axis knows to stop because it's reached it's home position.
On the left-hand side of the above photo are the fan plug (top) and the home switch plug underneath that. The emergency stop plug is the one with a red indicator light beneath.
