1. Version 1.1
Performing a Rub-Out
LPKF Milling Machine using Circuit Pro
GETTING STARTED 2
BASIC REQUIRED LAYERS 2
RUBOUT LAYER 2
IN THE TOOL PATH GENERATION & PRODUCTION WIZARD 2
SETTING UP TOOL PATH 2
TESTING MILLING WIDTH 2
TROUBLE SHOOTING 3
I’M GETTING A CIRCLE WHEN TESTING MILL WIDTH 3
CIRCUIT PRO IS ASKING FOR AN END MILL SIZE I DO NOT HAVE 3
SECTION 3.1 #
SECTION 3.2 #
SECTION 3.3 #
SUBSECTION 3.3.A #
SUBSECTION 3.3.B #
SUBSECTION 3.3.C #

2. GETTING STARTED
BASIC REQUIRED LAYERS
As with any Circuit Pro project, ensure that you have (at the very least) a board outline and
bottom layer. When you go to assign your rubout area,it is essential that anything you want to
remain as a copper trace is in Circuit Pro under the bottom copper layer (or top copper layer, if
making a two-sided board. If not, it [the trace/design] will be rubbed out if it lies within the
rubout layer area.
RUBOUT LAYER
In order to perform a rubout, you need to first establish a rubout boundary. The steps to do so are
as follows:
1. Go to the insert menu > rubout area > rubout layers
2. Move the window off the side in order to see your CAM view in its entirety.
3. Single click on one corner of desired rubout area.
4. Single click on the opposite corner of desired rubout area.
** Alternatively,you can create a rubout area of specific size using the coordinate system.
You should see a rectangle (colour depending on if boundary is on rubout top or bottom layer)
surrounding the areas you selected.
To perform a rubout of the entire board area,there are two options:
1. You can copy the board outline directly, and assign the second polyline to the rubout
layer.
2. In setting up your toolpath, you can simply select the full rubout option. Under ‘more
details’, select “board outline as the rubout layer. This will rubout all excess copper
across the entire surface enclosed by the board outline.
IN THE PRODUCTION WIZARD
SETTING UP TOOL PATH
When you first enter the tool path setup, you will need to change your insulation settings to a
rubout setting, either full or partial. To do so, follow these steps:
1. Press the technology dialogue icon or go to the toolpath menu.
2. In pressing the arrow keys on the screen to choose which insulation type you desire,
you will see two rubout options:
a) Partial rubout will isolate pads and traces,and remove excess copper within your
rubout boundary
b) Full rubout will isolate pads and traces,and remove excess copper from the entire
board.

3. TESTING MILLINGWIDTH
Testing the mill width for an end mill bit (the one used for rubout) works almost exactly the same
as other mill width tests with other bits. The only difference is that the length of your test line
must be less than the diameter of your end mill bit. Ex: when using a 2mm end mill, make a 1.5
mm long test line.
TROUBLE SHOOTING
I’m getting a circle when testing mill width?
Decrease your test mill line length to less than the diameter of your bit.
Circuit Pro is asking fora bit size that I do not have?
You will need to remove the tool that you do not have from the library:
1. Go to Edit > Tool Library
2. Find the bit that you do not have, and single click to select it
3. After selected,press the “remove Tool” button underneath the library window list.
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Author: Jessica Switzer
Last Revised: March 1, 2016