CNC Cut Files with Autodesk Product Design Suites, Part 2
This handout was written as a supplement to the Autodesk University 2013 class given by Scott Moyse and Gavin Bath. They were kind enough to permit it to be formatted in 2 parts and displayed here. Some of the information was covered in more or less detail to suit that limited class format.
Part 1 (AUGIWorld, March 2014) covered various methods of producing 2D CNC cut files or tool paths within Autodesk Inventor®.
The conclusion, Part 2, covers iPropWiz, a third-party tool you can use to prepare manufacturing information associated with your designs. This will provide an understanding of how you can configure your Inventor design environment to benefit you in the long run. Also discussed is the concept of using Autodesk Vault to manage your design data, then ultimately your CAM and manufacturing data and some methods of presenting that to CAM programmers and staff on the shop floor.
iPropwiz – Leveraging Your Manufacturing Information
iPropWiz is an Inventor add-in created to simplify and ease the management of component properties. iPropWiz presents all the properties you are interested in, within a single view. Over the years it has matured, moving way beyond just presenting properties to the user.
Figure 1: iPropWiz's non-modal dockable window
The iPropWiz property editor is a non-modal and dockable window, which means you can continue to work while it’s open. Being able to keep it on a second monitor means you are constantly aware of, and working with, the properties fundamental to the design and ultimately the manufacturing processes.
Figure 2: iPropWiz V6's configuration editor
Within the password-protected administration dialog box, you can set up formatting rules for physical properties, specify required properties, and manage lists and expressions. In addition you can configure iPropWiz to check property compliance in real time or upon closing the files. All this will allow you to create a more stable environment for iLogic rules, add-ins, or Autodesk Vault Professional to guide the users work in the correct direction for the benefit of CAM and manufacturing.
Lists and Expressions
The new list types are some of the most powerful new features in iPropWiz V6 (see Figure 3). The Multi-Property, Material, and Parameter based multi-property lists allow the administrator to monitor the value of a targeted property. When that property matches the criteria set by the list rule, it takes control of other preset properties. This can either be in the form of enforcing a value, or chopping and changing lists assigned to these controlled properties. Using material as a good example, steel has a different set of finishing requirements than plastic. These tools allow you to present those options to the user. Very cool stuff! In this article, we will use lists to create fixed values, which will drive the categorization of parts as they are checked into Vault.
Figure 3: iPropWiz V6 sports clever new list types
Model Properties Tab
Figure 4: The Model Properties tab provides conditional formatting of physical properties
Notice the 2,77,999 tick box just to the right of the Secondary Format Rule drop-down list in Figure 4. That little sucker enables sorting of the three Extents properties from the smallest to the largest. This means you can use property expressions to map Length to the largest value and thickness to the smallest—or whatever your standard may be. For instance, if you don’t select that option, you can permanently tie the Length property to the Extent in the X direction. In the woodworking industry, some companies would want to allow Inventor users to align the length property with the grain direction of the part.
As soon as the Extents tick box is enabled in iPropWiz Model Properties tab, it will create the following six custom iProperties:
Sheet Metal Properties Tab
iPropwiz provides three options for exported flat pattern area. By default, Inventor provides only one of these:
Outer loop area
Figure 5: There are a number of tools for managing Sheet Metal properties
The ability to automatically extract inner and outer loop distances can be utilized for pricing and planning CNC machine run times and consumable usage.
User Defined UCS and Component Extents
iPropWiz allows the user to place a User- Defined UCS onto a part, then use it to calculate the extents of the entire component relative to that coordinate system.
Figure 6: Create an iPropWiz UCS to calculate the extents of a component that isn't aligned to the WCS
With this in mind, you can now go back and take advantage of the Model Extents features mentioned earlier. The result can be seen in Figure 7.
Figure 7: Using an IPW User-Defined UCS enables you to pre-populate essential BOM information automatically
The next advantage of placing a User- Defined UCS is that it suddenly gives you an index for placing and orienting parts for CNC toolpathing and machining. For instance, the X axis can be aligned with any grain/pattern direction you may need to consider and the XY plane could be the bed of your CNC machine or clamp. Or maybe you have a saw blade add-on for your machine, but its axis is locked. With this you could ensure the appropriate axis is aligned with the modelled groove, which represents the saw cut.
Another way to take advantage of this information would be to create a little iLogic rule in your template document that could constantly keep an eye on the values, then inform the user when the part is too large to manufacture on any machinery at your disposal, or maybe exceeds the available stock size.
Delivering/Presenting Manufacturing Information with Vault
Delivering the CAM and manufacturing related information to those who need it has been referred to throughout this article. However, there are a few additional things that can be done with Vault to focus the view of end users within manufacturing. I’ll focus on different CNC operators to illustrate the example.
Figure 8: Create a group for each CNC type (above) and create CNC users and add them to their respective CNC groups (below)
Create a lifecycle for each CNC type.
Figure 9: The 3-axis Mill group can only see files participating in the CNC for their CNC type when the files are released
Create a Category for each CNC type and assign a Lifecycle Definition, a Revision Scheme, and all the properties you want enforced on files of that category.
Figure 10: The 3-axis Mill lifecycle has been assigned to the 3-axis Mill category
Now you can create a rule for that category so any files meeting the Rule Criteria when checked in for the first time get categorized automatically.
Figure 11: Using the Inventor CNC property, users can automatically assign categories upon first Check In
The idea behind this approach means you can configure Vault in such a way that CAM programmers and CNC operators can only see files which are relevant to them. You could expand on these lifecycles, allowing them to move the files off into another state once they have been programmed or machined, and so on.
You could then take advantage of Vault’s excellent reporting tool to present status information to management and clients.
If you don’t want users to have to rummage about in the depths of folder structures, you can simply create some search folders and combine them with some predefined custom views in much the same way as I did in the section on Parts Sorted By Material and Thickness into Assemblies below.
3D CNC Cut Files
This is where you start to see data management software come into its own. Vault isn’t just a means to look after your CAD data, but you can use it to make the most of the data and the information contained within it. We will now show you how you can use all that metadata to speed up the production of CNC cut files and get your designs to CAM faster.
Parts Sorted By Material and Thickness into Assemblies.
Using Vault’s Custom View tools, sort and group parts by material and thickness:
Figure 12: Create a custom view in Vault Explorer
You can also set up custom filters and other settings for your custom view. These tools can be surprisingly powerful once you learn to use them.
Figure 13: This is a sneaky Vault tip to get around the standard 'AND' nature of this dialog
Drag and drop the grouped parts from Vault Explorer into an Inventor assembly.
Figure 14: Drag and Drop CNC parts from Vault. Vault shows the custom filter created above activated
Constrain parts into place using the IPW User Defined UCS, aligning axis if appropriate.
Figure 15: Constrain IPW UCS with the assembly origin
Save the assembly into a folder of the same name using the material and thickness as the filename for the assembly. Use a unique identifier as well, such as a contract/project number.
Figure 16: Yellow highlight is the unique section of the filename
Check all the CNC cut file assemblies into Vault. You can dump them all into a blank assembly to check in at once if you want without checking in that ‘dummy’ parent assembly.
Inventor HSM Express
Inventor HSM Express is a free 2.5D fully integrated CAM system that runs inside Inventor and Solidworks. For prismatic components, this software allows you to very quickly generate quality CNC code to run your machine tools. For Inventor or Solidworks users, the HSM Express add-in can be downloaded from cam.autodesk.com. When installed, the add-in will add a CAM tab to your ribbon and also a CAM browser. Selecting either of these will take you into CAM mode shown in Figure 17.
Figure 17: CAM browser and ribbon loaded in Inventor
Like many Inventor workflows, you generally work from left to right across the ribbon. Starting with creation of setups, where you define stock size and orientation, you then move through the toolpath creation, which converts Inventor features to toolpaths automatically based on tooling, strategies, and other parameters specified by you. Toolpaths can be visualized as lines, or a simulation process can be run, which animates the tool movement. A still image from a simulation can be seen in Figure 18.
Figure 18: Toolpath simulation running
This simulation feature is invaluable for checking the logic the software has applied and ensuring the tool doesn't go anywhere untoward.
Once you are happy with your simulated toolpaths, the file can be post-processed to generate the G-code required to feed to your machine controller. This G-code can also be backplotted to ensure accuracy of the conversion and to visualize the instructions given by the code. If there are issues with the backplot, this can be an indication that modifications to your post-processor are required.
- Fully integrated with CAD package.
- Easy to use interface with good help.
- Fantastic support for developing post processors.
- Keeps the CAM data with the part file, reducing the number of files to manage and increasing the odds the correct version will be machined.
- Limited to 2.5D (no 3D operations; e.g., surfacing or helical interpolation. This will be in the paid version).
- Adds CAM data to part files which increases file size.
- No nesting.
Thank you to Gavin Bath for contributing a huge effort towards this article, and also CADPRO Systems Ltd for allowing this information to be shared publicly.