CopperCAM Gerber to GCode conversion program

 
An essential part of producing milled printed circuit boards is the ability to convert the Gerber photoplot files produced by most PCB layout tools to a format readable by CNC mill software to either isolate traces and pads or to "rub out" all copper on a board except traces and pads. You also need a tool to convert the common Excellon drill files to CNC language to drill the through holes and vias in the circuit board. In most cases, the CNC mill control software will require a program sequence in a language called G-Code which is a standard for many CNC machines. 

The expensive 2D CNC mills produced exclusively to mill PCBs from companies such as LPKF and T-Tech include such software. Finding a good third party software tool for this purpose can be duanting. We have looked extensively for these type of tools both commercial and open source. To date, we have not really found an open source package that is sufficiently full featured and robust enough to make it useful. Among the commercial packages, the best bang for the buck is CopperCAM.

CopperCAM is written by the French company that produces a fully featured CAD to CNC suite of conversion programs and machine control software called Galaad. CopperCAM is a low cost version of their Percival program for engraving and isolation routing. It only provides the Gerber and drill file conversion and does not provide any machine control. For machine control the two main programs in use are the commercial product Mach3 by Artsoft and the open source EMC2 supported by LinuxCNC.org. 

CopperCAM is a free download to try and evaluate with some features limited. A license may be purchased through Celeritous to fully unlock all of the features. 

CopperCAM features include:

• Native 32 bits program for Windows 95 / 98 / ME / NT-4 / 2000 / XP / Vista / 7
• Import of Gerber & Excellon files, with automatic or manual alignment
• Management of up to 4 circuit layers, plus drills, plus cut-out, plus centering holes
• automatic calculation of isolating contours, hatched surface pockets
• Allows routing of larger holes with a single tool, limiting tool changes
• Automatic calculation of board cut-out path, with manual addition of binding points
• Manual modification of isolation contours (deletion or addition with auto-snap)
• Selection of tracks to be engraved at path centre (texts, logos or references)
• Management of a tool library and drilling strategies depending to available cutters
• HPGL, DXF, G-code, Isel-NCP, Roland RDGL, Suregrave SML, Colinbus CBR, and user defined post-processeur output
• Automatic chaining to a machining driver, or output to a virtual printer driver or a COM / LPT port
   

CopperCAM's process sequence is simple :

• Opening of a Gerber file that contains one of the printed circuit layers
• For old Gerber RS274-D files, manual edit of apertures (shape & size)
• Opening of eventual next layers (4 circuit layers maximum)
• Detection (or manual plotting) of the board cut-out contour with tool compensation
• Detection (or manual plotting) and disabling of ground copper-planes
• Opening of an Excellon file for eventual drillings
• Automatic or manual alignment of layers (using a reference pad)
• Manual plotting of tracks that represent logos or texts to be engraved at centre
• Once the layers are aligned, automatic calculation of isolating contours
• Corrections on contours (additions between pads, deletions, connections, etc.) as required
• Manual plotting of hatched zones to remove the copper off a surface and ease the soldering job
• Addition of centering holes to give an origin reference on the reversed board as required
• Checking of drilling tools and boring cycles (if applicable) 
• Selection and saving control files or sending of data directly to the driver software or to the machine

You can download a limited evaluation version here: If you decide to purchase a license for CopperCAM a license key will be generated and sent to you in 24-72 hours. We have to request the license file to be generated by the manufacturer.

The video below is a brief tutorial going from generating Geber and drill files in Altium to importing, aligning and isolating the files in CopperCAM. From the point of importing the gerber and drill files into CoppeCAM forwards is PCB Cad neutral and applies to Gerber and drill files from any package.