Pocket NC V2 User manual

V2 Troubleshooting Guide

Table of Contents
Table of Contents 1
Revision History 1
Intro 1
Common Problems 1
Machining/Performance 4
Error Codes 6
Resetting/Updating the Machine 8
Revision History
First Release: October 2017 (JD)
Introduction
Our goal at Pocket NC is to produce an excellent product at an affordable price so that people
can turn their ideas into reality. We hope that using our product is a straightforward process and
the the machine functions perfectly. But, we know that things don’t always go perfectly.
Hopefully this troubleshooting guide can help you resolve some of the problems that come up.
If your problem is not covered here, or if you need some more information, please contact us.
For instructions on how to run the machine, set-up parts for machining, measure tool offsets and
other operation instruction see our tutorials.
1

Section 1: Common Problems
Problem
Possible Solutions
I can’t connect to my Pocket
NC or the user interface is
not loading correctly on my
computer.
1. Check that the Pocket NC is is plugged in and is
powered on. The red LED on the E-stop button will
light up when the machine is on. The user interface is
ready to boot when the red LED starts blinking. It
takes 2 and half minutes to fully boot the Pocket NC.
2. The computer must be connected to the mini-USB port
on the mill not the standard USB port.
3. The mini USB may not be fully plugged into the
machine. The pocket is deep so the plastic around the
plug may have to be trimmed to fit.
4. The machine may not be fully booted. Wait 1 minute
after turning on the machine before trying to connect.
5. The user interface may not load properly in every
browser. Try using Chrome, Firefox, or Safari
6. Try rebooting the machine: power off the machine,
unplug all the cords, wait about a minute for the
capacitors to drain then plug it back in and restart.
7. You may need a different driver. Try downloading a
new driver from the Beagleboard website.
8. Contact the Pocket NC help desk or post of the Pocket
NC forum for help.
The Pocket NC is
unresponsive, nothing
happens when I tell the
Pocket NC to move.
1. Check that the Pocket NC is plugged in and that the
power switch is on. The Pocket NC’s electronics can
run off computer power, but the motors can’t.
2. Make sure that the Pocket NC is not in E-stop mode.
When the machine is in E-stop the red button on the
machine will blink and the buttons in the upper right
corner of the user interface will be gray/white.
2

            Push the E-stop button to enable the motors.
3. Check that the computer is still connected to the
Pocket NC with the USB cord.
4. Try rebooting the machine: power off the machine,
unplug all the cords, wait about a minute for the
capacitors to drain then plug it back in and restart.
5. Contact the Pocket NC help desk or post of the Pocket
NC forum for help.
One of the axes on my
Pocket NC is not working
1. Try rebooting the machine: power off the machine,
unplug all the cords, wait about a minute for the
capacitors to drain then plug it back in and restart.
2. Check the electrical connections for that axis. Look for
damage and debris.
3. Contact the Pocket NC help desk or post of the Pocket
NC forum for help.
The Pocket NC motors are
noisy when the machine is
running
Particularly at low feed rates, the stepper motors can produce
quite a bit of noise. This is due to the electrical interference in
the driver circuit.
Increasing the feed rate usually decreases the sound.
The Pocket NC is not cutting
in the location that I
expected.
1. Make sure that the origin for your toolpaths is the B
table offset/machine origin point of the Pocket NC.
This is a point in space about 0.839 inches above the
center of the B table.
2. Check if the coordinate system of your machining
setup in CAM is set up so that the positive Z axis
points at the spindle of the Pocket NC, the positive X
axis points at the A table, and the positive Y axis
points straight up from the B table.
3. Check if the toolpath origin is also the B table
offset/machine origin point and that the toolpath
coordinate system is appropriate. Remember that the
Z axis is always the Pocket NC spindle.
4. Make sure that your stock is located in the same place
3

on your machine as it was relative to the origin point in
your CAM program.
I can’t find/load my G-code
file
1. Check if the selection set for the file type includes your
file extension (file type) for example you can’t find
machining files with a .nc extension if the selection set
is looking for only .ngc files
2. The file must be a text file that the Pocket NC is
capable of reading. Generally these will have a
extension like .ngc, .nc, or .cnc but any machinable file
should work.
4

Section 2: Machining/Performance Issues
Problem
Explanation
Possible Solution/Things to Try
My tool chatters during
the cut.
Vibration causes the cutter
to not cut smoothly. This
vibration is due to the
natural frequency of the
tool/spindle.
1. The feed and speed, and/or
step-down and step-over
need to be adjusted. See
the feeds and speeds
tutorial for more
information.
2. Turn the spindle speed up.
3. Adjust the feedrate, usually
moving slower will be
smoother, but this is not
always the case
4. Increase the step-down,
taking a deeper cut into the
material
5. Increase or decrease the
step-over, the width of the
cut. Typically the ideal
step-over is about 60% of
tool diameter.
Spindle sounds like it is
slowing down during the
cut.
The spindle power is
insufficient for the amount of
material being removed.
1. Decrease the feed rate in
5% steps until the spindle
stops bogging down
2. Decrease the step-down
and step over in your
toolpaths.
3. Switch to a tool with more
cutting flutes.
The Pocket NC is not
cutting in the location
that I expected.
1. Make sure that the origin
for your toolpaths is the B
table offset/machine origin
point of the Pocket NC.
This is a point in space
about 0.839 inches above
the center of B table.
5

The stock may not be
located in the same position
relative to the origin point
that it was in the CAM
software used to create the
toolpaths
2. Check if the coordinate
system of your machining
setup in CAM is set up so
that the positive Z axis
points at the spindle of the
Pocket NC, the positive X
axis points at the A table,
and the positive Y axis
points straight up from the
B table.
3. Check if the toolpath origin
is also the B table
offset/machine origin point
and that the toolpath
coordinate system is
appropriate. Remember
that the Z axis is always the
Pocket NC spindle.
4. Make sure that your stock
is located in the same place
on your machine as it was
relative to the origin point in
your CAM program.
The drive/lead screws
squeak.
The end of the lead screw is
touching the frame of the
machine when it turns.
1. Make sure that the screw
and the hole are free of
debris.
2. If the noise it minor is is
best to let it wear into
position. The noise should
decrease with time
- Use a very small amount of
general purpose synthetic
grease to lubricate the tip of
the screw.
- Do not grease the whole
screw.
- Do not put grease where it
will contact the
anti-backlash nuts.
- Grease will collect debris
and may cause increased
wear on your machine.
6

Section 3: Error Codes
Error Code/Message
Explanation
Possible Solutions
Near Line XX Linear Move
Exceeds Joint X’s
Positive/Negative Limit
This error means that the
toolpath/G code is telling the
machine to go past one its
travel limits
Joint 0 = X axis
Joint 1 = Y axis
Joint 2 = Z axis
Joint 3 = A axis
Joint 4 = B axis
This error is often caused by
a tool length offset being set
incorrectly or by a part that is
outside the Pocket NC’s
work envelope.
The move that is causing the
error is located on or near
the line of the program
indicated
1. If the error is on joint 2 (Z
axis), check if your tool
length offset is set
correctly. See the “Tool
Length Offset” tutorial for
more information.
2. If the error is for
exceeding the negative
limit of joint 2 and the tool
length offset is correct,
increase the tool stickout
or switch to a longer tool
holder.
3. If the error is for
exceeding the positive
limit of joint 2 and the tool
length offset is correct,
decrease the tool stickout
or switch to a shorter tool
holder.
4. Check if your toolpath is
asking the machine to
exceed its limits of travel.
Open your code in a text
editing program and use
the search bar (CTRL +
F) to search for any
values that are greater
than the limits of travel for
the Pocket NC mill.
a. The X limits are
-2.00 to 2.55
inches
b. The Y limits are
-2.4 to 2.6 inches
c. The Z limits are
7

-3.45 to 0.10
inches*
d. The A limits are
-25 to 135
degrees
e. The B limits are
-9999 to 9999
degrees
*you have to add the tool
length offset to the Z axis
value
5. Adjust the location of the
part/stock so that it is
within the Pocket NC’s
work envelope
6. Decrease the retract
height on the toolpaths if
the part is close to the
limits of the Pocket NC’s
travel.
7. Oversized parts may be
able to be fixtured and
cut one side at a time
instead of all in one
program.
14 Unexpected Real Time
Delay on RT Thread 1
This error means that there
has been a delay in the
Beaglebones processor.
1. This error can be caused
by a temporarily dropped
connection between the
computer and the Pocket
NC mill or by a program
that is so large and
complicated that the
Beaglebone’s processor
cannot keep up.
2. Check that the
connection between the
computer and the
machine is good.
3. Try slowing down the
feed rate or reducing the
file size of the G code file
8

by breaking it into more
than 1 operation or by
loosening the tolerances
in the toolpath and
reposting it.
Section 4: Resetting/Updating the Machine
This section will have instructions on how to update the machine when that capability is
available.
This update process will require an internet connection through the ethernet port on the Pocket
NC.
9