QuickCompare, a module in Cimatron E, detects and manages engineering changes. It produces part-to-part comparisons of CAD geometry from originals to new parts. It detects new features, alterations to existing features, and shape changes.
The QuickSplit module separates a model into core, cavity, inserts, and slides. A parting or split line can be established on surface and solid models.
QuickElectrode analyzes, extracts, creates, documents, and machines electrodes. A feature guide assists in extracting electrode surfaces, developing extension surfaces, selecting a blank, base, and holder, determining burn locations, and creating inspection drawings.
The user interface is well structured and easy to learn. Toolbar docking lets users position toolbars. Even with access to a number of tool bars and dialogue boxes, the software leaves considerable workspace on screen. And the developer has added several modules for specific mold-building functions.
Process Guides assist novices with prescribed workflows. For example, when the task is to split a core and cavity, the steps are to determine a shrink allowance, analyze the model, establish parting lines and surfaces, and export the core and cavity. Users are led through appropriate dialogue boxes for each step. Specific operations and components are captured and shown in a tree. The system also tracks what has been done and what is left to do to complete the task.
Default suggestions are included, but the software gives users options for final decisions. A click on the right mouse button brings up possible commands. For example, when selecting shrinkage allowances in the Feature Guide, the default is uniform shrinkage. There is, however, an option for nonuniform shrinkage. Built in checks ensure programmers complete all necessary steps and an integrated PDM module helps manage information.
To import and export data, there are direct translators for files from Catia V 4 (and soon V5), Unigraphics, Pro/E, AutoCAD/Dwg, and Parasolid IGES and ACIS-based models. The software also supports AutoCAD DXF, STEP, SLA, SAT, VRML and VDA formats. Most translators are bidirectional.
The software includes tools for fixing nonmanifold surfaces and those badly trimmed, converting surfaces to solids, and for closing objects. The software checks for open faces, but a closed, solid object is not required for data manipulation as it is in some solid modelers.
The software's parametric and hybrid modeling can generate designs, manipulate imported data, and prepare designs and their tools for manufacturing. At any time users can create, analyze, and edit geometry. They can add fillets, split part geometry, smooth parting surfaces, create electrodes and inserts, find and implement engineering changes, or detail tooling components. After the system detects undercuts, users decide whether they are acceptable or not.
A drafting function generates drawings, shop-floor documentation, and an itemized bill of material. For electrodes, it automatically produces assembly drawings, burning sequences, and location reports. A series of templates could be established for making drawings. A user could then use or modify the templates as appropriate.
MoldDesign, a section of the CAM software, helps users make single and multicavity molds. A guide leads users through the task and has functions for proper mold positioning in a base, determining appropriate mold plates, and establishing a locking mechanism.
The program contains Hasco and DME mold-base libraries, and more are promised. Users can pick plates from libraries, along with a range of mold components such as guide pins, leader pins, screws, and ejectors. The software is associative, so when a part changes, its mold design changes. MoldDesign outputs include an itemized bill of materials, mold-base assembly drawings, and detailed drawings of each plate.
A few notable features in the basic machining module include the NC Process Guide. It has icons for major programming functions such as load model, pick cutter, and define stock. Some mandatory operations display in red. Finishing a section puts a check mark on the process tool bar.
An NC Assistant illustrates each machining strategy or parameter. For example, when uncertain about a cutting style, the system shows what it means. Models and machining operations are also associative. A special roughing technique for core machining, Stock Spiral, maintains a constant chip load and always cuts from the outside in. All roughing options make rounded corners because sharp-corner motions are ill advised in high-speed machining.
Pockets can be cut level by level or pocket by pocket. Level-by-level pocketing works well for machining thin-walled objects. Pocketing can have an unlimited number of objects. The software sorts and machines nested pockets in a single operation.
The QuickDrill module examines faces for holes, their characteristics, and parameters. Analysis determines whether a cavity is a hole or a pocket and whether a hole should be drilled or milled. Characteristics could include hole diameter, depth, through hole or not, threaded or not, and tolerances. The software places holes into groups for production and drilling sequences are optimized to minimize the total distance from start to finish.
For three-axis milling, the software sports a wide range of features, including machining on a single surface or parallel-plane, spiral inside-out and outside-in, and radial cutting with an angle stepover around a point. Rest machining removes material left behind by large tools that do not reach into corners and depressions. The strategy selects a smaller cutter and refigures toolpaths for areas with remaining material.
The software checks for gouging on all moves and highlights them in red. Cutting tools, shanks, and toolholders are included in collision checking three and five-axis milling.
Adaptive feedrate control, another useful feature, lets users specify a range of feedrates. The idea is to modify feedrates as tools approach corners to maintain a constant material removal rate. Users can specify feedrates for any points along the toolpath.
Knowledge-based machining uses a parts-based, template approach. Full or partial machining processes are captured in templates and applied to machine similar parts. Capturing the knowledge of experienced programmers assures consistency in programming and machining, and avoids repetitive user interaction. The templates, in effect, define and document a shop's best practices.
One high-speed machining option makes rapid moves on arcs, rounds internal and external corners, and rounds movement between passes.
The developer licenses MachineWorks for toolpath verification and postprocessing. Simulations include fixtures with parts, tools, and holders. One can also zoom in or rotate models during simulation. The software contains a library of postprocessors. Custom postprocessors are typically generated by Cimatron subsidiaries and resellers.
Cimatron E V4.2 comes from Cimatron Ltd., 21555 Melrose Ave., Suite 16, Southfield, MI 48075, (810) 799-8905, www.cimatron.com.
- John MacKrell
John MacKrell is a principal consultant with CIMdata Inc. (www.cimdata.com), an independent worldwide strategic PLM consultancy. The company helps firms design and deliver products and services using PLM.