General

The purpose of ColiCAM software package is to calculate and generate toolpaths for machining of various objects on milling machines.

Source data for calculation and generation of toolpaths are drawings of objects to be machined. These drawings are usually created with help of various CAD software packages. One of such packages is AutoCAD from Autodesk. For farther processing by ColiCAM, the completed drawings have to be exported to a disk file in one of supported data formats. The task of exporting graphics of the drawing is usually a part of CAD software.

Current version of ColiCAM may import drawing images in following formats

• Autodesk Drawing Exchange Format (DXF)
• Hewlett Packard Graphic Language (HP-GL)

The procedure for generating of complete machining program consists of following steps:

• Import of drawing image in one of supported formats (DXF or HP-GL)
• Optional editing of imported drawing − for example it may necessary to remove redundant graphical elements or interactively close selected open shapes
• Setting up general parameters like stock dimensions, preferred origin of coordinates and eventually default machining parameters
• Creating machining geometries by selecting shapes from imported drawing
• Defining toolpaths by selecting required tools from Tool Database
• Applying machining strategies and setting up individual machining parameters for each defined toolpath
• Ordering program to calculate trajectories for defined toolpath
• Output (to a disk file) of resulting machining program in the format accepted by milling machine

Current version of ColiCAM may output machining programs in one of following formats:

• Generic
• RS274GC G-CODE
• Basic ISO CNC code
• Hewlett Packard Graphic Language (HP-GL)

Project database

ColiCAM stores all information about machined object in project database that at any stage can be saved to disk file. Internal precision (minimal unit) of the database is 1/100000 mm. Coordinates and sizes are stored with this precision. Angular values are stored with precision of 1/1000 degree. The software can process drawings with maximal size of 4400 by 4400 millimeters.

Project Database consists of imported drawing, selected geometries and calculated toolpaths trajectories. This information is presented graphically on computer screen. Project Database includes also numerical data. These data are several types of parameters that are set while preparing machining program for output. Current parameters’ settings are presented (and may be at any timed modified) in tabular form on various pop-up dialogs.

Diagram below presents the structure of ColiCAM project database:

Machining strategies

Algorithms applied to calculation of toolpath trajectories depend on topology of shapes transferred to geometry and selected machining strategy.

Following machining strategies are available in ColiCAM:

• FACE − used to take out material to specified depth over whole surface of the stock.

• PARALLEL − used to take out material to specified depth within boundaries of closed shapes or between boundaries of the stock and boundaries of closed shape inside the stock. This strategy is always combined with PROFILE as then next step in order to finish outline of the take-out.

• SPIRAL − used to take out material to specified depth within boundaries of closed shapes. Toolpath trajectory for this strategy is calculated is such way that finishing outlines with PROFILE is not necessary.

• PROFILE − used to cut out outline of closed shapes internally or externally.

• SLOT − to cut along outlines of shapes (closed and open) with or without offset of ½ of tool diameter.

• STROKE FILL − used for taking out material in parallel strokes within boundaries of closed shapes. This strategy is usually applied for machining shapes constructed as strips.

• DRILL − drilling holes

Editing function

Imported drawings are not always suitable for extracting geometries for machining. To solve that problem ColiCAM provides a set of advanced features that allow editing imported drawings. Editing functions tools enable to relocate and transform shapes. There are also functions for constructing shapes for machining from elements of other shapes. Apart from operating on imported shapes, new shapes may be manually added to drawings.

Editing functions can be therefore treated as simple CAD system integrated within ColiCAM. Using these functions the user can actually create drawings of object to be machined directly in ColiCAM, without necessity to import drawings generated by other CAD packages.

Documenting features

Saved to disk project database and generated machining programs are not the only outputs from ColiCAM. Working session may be documented in other three different ways:

• Contents of graphic screen may at any time copied to Clipboard and then pasted as bitmap to other documents
• Project may be printed in any scale on a color or black & white printer
• Build up of machining programs may be stored in plain text file and presented in Notepad