Stock Models are a great tool for showing step by step material removal in PowerMill, here are some tips when using them and best practice applications.
Through many conversations with PowerMill engineers and our own experience, we’ve gathered these tips for using Stock Models & Rest Roughing in PowerMill. These suggestions should be used as a starting point to develop the best strategy for your application.
- Keep the model as clean and simple as possible. Delete duplicate surfaces and ensure surfaces are trimmed properly.
- If the “detect material thicker than” value is used, “Expand area by” should also be used with the same value. Otherwise, rest roughing may take a radial cut larger than expected
Settings for Stock models:
- Tolerances: Set the tolerance to the lowest value you will use during “Stock model machining.” A tolerance of .005 - .008 is reasonable. A “tighter” tolerance will give a more accurate representation of the stock but will slow the process.
- Step over: It is equally important to apply a step over that is 50% of the smallest cutter you will use with the stock model. Tighter than that and you will get better results but it will take longer to calculate.
- In the proper order, apply only the toolpaths that you have used to cut your workpiece.
- After applying each toolpath, you must recalculate your stock model to achieve the current state of your stock condition.
- Here is another simple macro that will automatically apply the active toolpath to the last state of the active Stock Model and calculate it.
- Use the option "Detect material thicker than" under rest roughing to control what will be cut.
- Check the box on the Offset Area Clearance form advanced tab "Allow tool Outside Block".
- Remember, you can use the "Show rest material" option on the stock model to visually show you what PowerMill will be looking at to cut.
- When you save the project, after viewing the stock model in shaded mode, PowerMill will save a file for the shaded stock model. This file can become very large and take a while to save. If you use the option "Remove triangulation" before you save, it will not save the large file.