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Once the toolpaths are computed correctly, it is possible to proceed with PCB production. The whole course of PCB production is divided into phases, each with its own collection of commands and toolpaths. Table 5.1 shows a list of all phases with at least one command or toolpath. Starting the Board Production Wizard under the Wizards tab will process each phase’s commands and toolpaths in the default order. There are many orders in which the phases and toolpaths may be processed, but the first four phases in Table 5.1 should always be processed first.

For the rest of this chapter, photographs and screenshots will provide hints and guidance for each production phase in the default order. It should be noted that the example PCB created in this guide had solder mask applied to its top layer, so the photographs will show a PCB that had its through-holes drilled after the top and bottom layers were milled. For information on applying solder mask to a PCB, see the Solder Mask tutorial. For information on processing or reprocessing phases in a custom order, see the Reprocessing tutorial.

Table 5.1: Production Phases in the Default Order.
The default order is recommended if no solder mask is being applied. The first four phases should always be processed before the others.

Production Phase	Tools Used	Description
Mount Material		Secure the FR4 copper-clad material on the moving table
Material Settings		Specify the thickness and dimensions of the material
Placement		Select location, orientation of board. Select number of copies
Drill Fiducial	Spiral Drill – 1.5 mm	Drill holes for board alignment
Marking Drills	Universal Milling Tool	Mark the location of through-holes to be drilled
Drill Unplated	Spiral Drill – All Sizes Long End Mill – Both Sizes Contour Router – Both Sizes	Drill through-holes with the spiral drill and widen them if necessary with long end mills and contour routers.
Milling Bottom	Micro Cutter Universal Milling Tool End Mill – All Sizes	Insulate traces on the bottom side by milling away copper
Flip Material		Turn the material over to mill the top side
Read Fiducials Top		Locate the fiducials with the microscope to realign the board
Milling Top	Micro Cutter Universal Milling Tool End Mill – All Sizes	Insulate traces on the top side by milling away copper
Contour Routing	Spiral Drill – 1.0 mm Contour Rounter – 1.0 mm Spiral Drill – 2.0 mm Contour Router – 2.0 mm	Cut out the board outline, leaving small breakout tabs of substrate where requested.

! Safety Precautions ! Read Before Operating ProtoMat !

Before proceeding with each production phase, either in a custom order or guided by the Board Production Wizard, please read the bulleted safety precautions below and follow them to avoid damaging the ProtoMat or inflicting personal injury.

• Never open the hood of the ProtoMat while it is moving or processing a toolpath. Wait until it is finished moving before opening the hood. Do not issue a movement command or begin processing a toolpath if the hood is open.
• Do not rock the table or lean on the table while the ProtoMat is moving.
• Turn on the Vacuum Unit (shown in Figure 5.1) before drilling, milling, or routing a toolpath. Turn the Vacuum Unit off before leaving the lab station
• Do not apply pressure to the tip of ProtoMat tools with bare skin. The ProtoMat tools can puncture skin and draw blood.

Figure 5.1: Vacuum Unit
It is located under the table. Use the red power button to turn it on and off.

Production Phase – Mount Material

Before attaching the copper-clad FR4 substrate onto the moving table as prompted by the window shown in Figure 5.2.1, mount the cardboard support material shown in Figure 5.2.2. The cardboard support material can be used many times, but it may be necessary to replace or clean it if there is too much dust buildup in the cracks left by previous projects. The dust can cause the overlying substrate to set unevenly. After mounting the cardboard, mount the FR4 substrate and tape its perimeter as shown in Figure 5.2.3.

Figure 5.2.1: Mount Material Prompt

Figure 5.2.2: Cardboard Support Material

Figure 5.2.3: Mounted Material
Use painter’s tape as shown to affix it to the table.

Production Phase – Material Settings

The Material Settings window shown in Figure 5.3.1 allows you to enter the thickness and bounds of the material mounted in the previous phase. The thickness settings shown in Figure 5.3.1 must be used or the remainder of the production phases will fail.

Figure 5.3.1: Material Settings Window
The copper thickness, material thickness, and underlay plate thickness must be 35 um, 3mm, and 6 mm respectively.

After closing the ProtoMat hood, you may set the rectangular bounds of the material by clicking somewhere in the Machine View as shown in Figure 5.3.1. This click issues a movement command that places the active head over the location clicked. You may then click the lower-left corner and upper-right corner buttons on the material settings window to set the lower-left and upper-right bounds of the material. Figure 5.3.2 and Figure 5.3.3 show the lower-left and upper-right locations, respectively.

Figure 5.3.2: Lower Left Corner
This point was chosen to keep the active head away from the previous project’s area.

Figure 5.3.3: Upper Right Corner
This point was chosen to keep the active head from touching the perimeter tape.

Production Phase – Placement

The Placement window, shown in Figure 5.4.1, allows you to select where your board will be created within the material bounds, which direction it will be facing, and whether or not there will be multiple copies made. Drag your board outline in the Machining view to select its location and use the Rotation field in the Placement window to select its orientation. Check the machining view to ensure that all of the board outlines lie on fresh copper that can be milled into a circuit board. Figure 5.4.2 shows an acceptable board placement.

Figure 5.4.1: Placement Window
Use the Step and Repeat fields to make multiple copies of your PCB.

Figure 5.4.2: Board Placement
The board outline (black) rests within the material boundary (orange).

Changing Tools

To replace the tool currently being wielded by the ProtoMat, grab the knob on top of the Active Head shown in Figure 5.5.1. If you lightly press down as shown in Figure 5.5.2, the knob will rotate freely. While applying slightly more force, rotate and nudge the knob until it aligns with the tool shaft and presses down completely, as shown in Figure 5.5.3. When the knob pushes down after alignment, you may tighten or loosen the tool shaft’s grip on the current tool by turning the knob clockwise or counterclockwise respectively. When the old tool is loose enough, it will fall and hit the base of the ProtoMat. Hold one hand underneath a loosened tool to catch it and preserve its lifetime. Promptly place this tool back in the toolbox and then grab the new tool. Push the new tool into the tool shaft until its collar is flush as shown in Figure 5.5.4. Then tighten the knob until the tool is firm.

Figure 5.5.1: Tool Gripping Knob in Default Position

Figure 5.5.2: Tool Gripping Knob being Slightly Pressed

Figure 5.5.3: Tool Gripping Knob after Alignment
The knob will need to be turned under pressure before it will align.

Figure 5.5.4: New Tool Being Inserted
Ensure that the collar is flush against the tool shaft. Use your fingernail to apply upward force. Do not release the gripping knob until the tool is tightened.

Production Phase – Drill Fiducial

This phase consists of four fiducials being drilled with the 1.5 mm size. If there are multiple copies of your board being created, then each board will have its own set of fiducials drilled. CircuitPro will prompt you to insert the Spiral Drill – 1.5 mm tool. Open the hood, change out the tool, and close the hood before hitting continue.

After this phase is processed, the Board Production Wizard will prompt you to perform the Marking Drills phase. You may continue with the wizard or you may abort and perform the toolpaths in a custom order. See the Reprocessing tutorial for individual toolpath processing/reprocessing. If there is a malfunction due to improper tool or material attachment, restart the wizard and change placement settings to avoid any copper areas damaged by malfunction.

Production Phase – Marking Drills

This phase consists of making small dots in the copper surface in the locations where holes will be drilled in the next phase. This is done to improve the accuracy of the drilling phase. This phase will be skipped if your PCB design does not have any through-holes.

CircuitPro will prompt you to insert the Universal Milling Tool, which is the most common tool (there are ten of them in the toolbox). You will have the option to adjust the milling width in the tool changing window, but that is not required in this phase, so you may press the Continue button after replacing the correct tool.

This phase should be processed after milling the top and bottom sides if your PCB is using solder mask. See the Solder Mask tutorial for more information regarding solder mask application.

Production Phase – Drill Unplated

This phase does not require much manual technique to perform. Simply provide the tools that the Board Production Wizard or processing dialog asks for. It might be wise to inspect the size and position of the newly drilled holes before proceeding to the next phases. If solder mask is to be used, it should be applied before drilling holes. See the Solder Mask tutorial for more information.

Production Phase – Milling Bottom

The milling phases require the most user intervention and the diligence of the user will determine the quality and precision of the final product. The milling phase may require as many as five different tools and each of them will require testing and adjusting to produce satisfactory results.

To understand what correct milling operation looks like for each tool, the operator must first understand how the milling toolpaths are supposed to be implemented. The milling toolpaths were computed to recreate the PCB design by removing copper in circular apertures, or milling widths. Figure 5.9.1 illustrates the concept.

Figure 5.9.1: Milling Stages
The colored circle or dot shows the relative milling aperture size.

As shown in Figure 5.9.1, the tools with the smallest apertures are used first. The Micro Cutter (0.1 mm) will mill corners, fine details, or any region too small to be milled by the other tools. In widely spaced designs, the Micro Cutter is not required at all or will mill an insignificant portion of the design. In designs with closely spaced SMT pads, the Micro Cutter’s calibration is crucial to electrical integrity.

The Universal Milling Tool (0.2 mm) does the majority of the precision work that is less precise than traces assigned the Micro Cutter, so the calibration of the Universal Milling Tool is very important. In most designs, the Universal Milling Tool will completely outline all traces.

The first two milling tools, the Micro Cutter and Universal Milling Tool, have a conical shape, which means that the lower they are pressed into the copper, the wider cut they leave behind. A cross section of such a cut is displayed in Figure 5.9.2. When the dialog prompting the operator to exchange either of these tools is shown, the operator may either click the Continue button, or may click the Measure Milling Width button, the latter of which is recommended for precision.

Figure 5.9.2: Conical Milling

Clicking the Measure Milling Width button makes the window in Figure 5.9.3 appear. Before proceeding, ensure that the ProtoMat hood is closed. On the Machining view, select a testing location by left clicking somewhere on the Machining view. This will cause the Active Head to slide to that location. The symbol shows where the test line will be drawn. Ensure that the line chosen does not intersect with the PCB design, as shown in Figure 5.9.4. Also ensure that the copper underneath the prepared milling tool has no scratches, marks, smudges, or other optical contaminants. After selecting a location for the test line, click the Mill a Line button and wait for CircuitPro to deliver another prompt. The Fiducial Recognition Microscope will automatically focus on the milled line and will ask for a focus confirmation which may be accepted. The Camera window, as shown in Figure 5.9.5, should show a focused line with clearly marked boundaries.

Figure 5.9.3: Conical Milling

Figure 5.9.4: Example Test Line Location
Any point in a fresh copper area outside of the PCB design is acceptable. Selecting the point shown in the figure will raise an error because it is technically inside the PCB’s black bounding box. The error can be ignored in this example because that part of the copper is unused.

Figure 5.9.5: Clearly Identified Line

After the microscope has finished focusing, the measurement window will display an automatically measured line width in millimeters, as shown in Figure 5.9.6. The purpose of this procedure is to make the measured line as close to the nominal milling aperture as possible, which is 0.1 mm for the Micro Cutter and 0.2 mm for the Universal Milling Tool.

Figure 5.9.6: Successful Line Measurement
The line was measured to be 0.1991 mm wide, which is acceptably close to the intended 0.2 mm. Note that if there are more than two yellow lines drawn on the Camera View, you may click two points on the camera view to measure the width manually.

If the measuring width is incorrect by a margin greater than 0.01 mm, or if no line was found, it is recommended to open the hood of the ProtoMat and turn the micrometer adjustment screw shown in Figure 5.9.7 in the direction suggested by the Measure Milling Width window. The window also suggests an amount to turn the screw, which might overcompensate or undercompensate the error. After finishing the adjustment, close the hood and click the Mill a Line button to repeat the procedure until satisfactory calibration is obtained. Click the Accept Width button to continue PCB production. If another measurement is required, the test line location will automatically be moved from the previous location, which might or might not provide a clear testing location.

Figure 5.9.7: Micrometer Adjustment Screw
Turn counterclockwise to lower the tool and clockwise to raise the tool.

After the Micro Cutter and/or Universal Milling Tool have completed their toolpaths on the bottom layer, it would be wise to inspect the traces and ensure that there are no insulation errors that could compromise electrical integrity. A picture of a successful milling is shown in Figure 5.9.8. If there are any traces that require re-milling, it is possible to exit the Board Production Wizard and reprocess the individual traces as explained in the Reprocessing Tutorial. If the tools cut too deep and the copper traces are too thin, it might be necessary to restart the entire PCB production.

Figure 5.9.8: Bottom Side after running the Universal Milling Tool and Micro Cutter

After the conical tools with the orange sleeves have finished their toolpaths, the purple-sleeved end mill tools might be required to mill additional insulation. These tools have broad, fixed circular apertures designed to wipe out copper in large portions. Figure 5.9.9 shows how an end mill removes the copper coating. Figure 5.9.9 also shows how the end mill might insufficiently remove copper. Because of this, the user has the option to click the Measure Milling Width button when prompted to insert any of the end mills.

Figure 5.9.9: Cross Section of End Milling
The left cut is deep enough to provide insulation and will appear as a dark mark. The right cut is not deep enough and will appear as a shiny, polished valley.

The micrometer adjustment screw must be adjusted in a fashion similar to that of the conical tools so that the end mill cuts deep enough to remove all of the copper in its path. However, unlike the conical tools, rotating the micrometer adjustment screw counterclockwise does not increase the width the milling aperture, it only causes the end mill to cut deeper into the board. Because end mills produce lots of friction, they wear down and shorten over the course of long toolpaths, which can result in incomplete milling and require toolpath reprocessing as explained in the Reprocessing Tutorial.

When the operator selects a test line location and clicks the Mill a Line button like in Figure 5.9.3, the ProtoMat will instead mill a small spot without focusing the camera onto the newly created spot. This is because milling width does not change over the end mill’s lifetime. It is only necessary to inspect the created spot and ensure that the copper in the spot was removed successfully. If not, rotate the micrometer adjustment screw counterclockwise and try again. Figures 5.9.10-12 show the milling results after the End Mill – 0.8 mm, End Mill – 1.0 mm, and End Mill – 2.0 mm have been applied, respectively.

Figure 5.9.10: Bottom Side after running the End Mill – 0.8 mm tool

Figure 5.9.11: Bottom Side after running the End Mill – 1.0 mm tool

Figure 5.9.12: Bottom Side after running the End Mill – 2.0 mm tool
NOTE: After the photograph was taken, it was discovered that solder mask will peel and flake off if this much copper is removed.

Production Phase – Flip Material

After finishing the milling bottom phase, the Board Production Wizard will prompt the user to flip the material. If a phase or toolpath is individually being processed, the material should be flipped to the correct side before issuing any commands.

To flip the material, remove the tape holding it to the table, lift and rotate material top to bottom, and reaffix the material with the removed tape. If the milling bottom layer was on the left side of the moving table before flipping, it should still be on the left side after flipping.

In preparation for the next phase, the user should wipe the four fiducials with a paper towel to remove dust and optical contaminants.

Production Phase – Read Fiducials Top

After flipping the material, the Board Production Wizard will initiate the Read Fiducials Top phase. This phase will also be invoked if a toolpath on the top side is processed individually. Before reading the fiducials, the Fiducial Recognition Microscope will automatically focus and ask for user-confirmation. Once focused, the camera window will show an automatically located fiducial as shown in Figure 5.11.1.

Figure 5.11.1: Fiducial with Good Alignment

When the camera locates a fiducial, it will either ask for confirmation if it was found easily, or it will show the window in Figure 5.11.2, asking the user to align the fiducial manually. To do this, use the Processing Panel shown in Figure 5.11.3 to move the camera head by a few micrometers in the correct direction. When the yellow circle in the Camera view is aligned with the Fiducial, click the Accept Current Position in the Alignment window to move on to the next fiducial. After all fiducials have been located, the PCB will be aligned and top side phases can be processed.

Figure 5.11.2: Alignment Window
The camera in this case should be moved a few micrometers up and to the right to improve fiducial alignment.

Figure 5.11.3: Processing Panel
Use the controls on the X/Y – positioning area to nudge the camera into position.

Production Phase – Milling Top

The top side of the PCB is milled in the same way the bottom side is milled. See Production Phase – Milling Bottom for detailed instructions and hints.

Production Phase – Contour Routing

The last phase of board production is very simple. Simply provide the tools that CircuitPro requests. If the toolpaths are being processed individually, as opposed to following the Board Production Wizard, run the Spiral Drill – 2.0 mm first before running the Contour Router toolpath. It will be difficult or impossible to make further modifications to the board after processing this phase, so ensure that you are satisfied with the milling and through-hole drilling. It is also especially important that the vacuum is running during this phase, as contour routing produces a lot of debris.

Disconnecting the ProtoMat

When you are satisfied that the ProtoMat is finished making the board and will no longer be needed, untape and remove the material with your board connected to it. After removing your board, close the hood, and select the “Connect” command from the Machining tab. Then select the option to disconnect and then cancel the window. After the ProtoMat finishes moving, open the hood and throw the power switch to the OFF position. You may then exit LPKF CircuitPro.

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