Check Surfaces / New Release
I’ve been working for a few days with a large company to see if MeshCAM can be used to automate their machining process. They have a few things that need to be added and then a bunch more existing features that will have to be exposed via the Lua scripting. Largely these changes match my existing plans so I’ve decided to give it a shot.
The first change was the need to add Check Surfaces. These are additional polygon/STL surfaces that are used to represent things like tooling, shutoff surfaces, and parting surfaces. The tool is never allowed to gouge them but they do not necessarily represent a feature of the final part.
An example of their use is shown below:
The sphere on the left has a hole that would be better drilled than parallel milled. You can always drill after parallel machining but it may be better to protect the edge and not plunge into there at all. The photo on the left shows a check surface that was saved as a separate STL file and loaded with the new "Load Check Surface" script. There are two different surfaces- a plug for the hole and a wavy surface that could represent a complex parting line. The important thing to note is that they do not count in the geometry dimensions(note the stock dimension do not change) – they are only used in the toolpath algorithms as an additional intersection test.
Practical uses for this feature-
- Modeling a vise, clamps, or a machining fixture
- Capping areas that would be poorly machined or that would be only partially machined
- Limiting the machining volume to the minimum required by defining a "parting surface"
- Defining your own tabs or supports
There is a second script that removes the check surfaces without changing any other parameters. This may be useful if you have a more complicated machining strategy in mind.
In the very near future the scripting ability will be expanded to allow offsetting and rotating the check surfaces. Scripts will then be able to do things like automatically place vise jaws so they touch either side of the geometry to simulate clamping.
Download it at http://www.grzsoftware.com/files/MeshCAM2-6926.exe or check for updates.
Finally- Save Toolpath Settings
I’ve been trying to work through some problems for Brett P. and he got me thinking that I need a way to duplicate as many user settings that a customer uses to reproduce some bugs. This got me thinking more about the Lua code I’ve got built it and it turns out to be a very good data parser. I was able to implement the ability to save and load toolpath settings in about two afternoons once I figured out how I wanted to do it. The data is all saved as a Lua table which is editable outside of MeshCAM if you want.
I have to do a little more to save the tool properly. It currently saved the tool index in the saved tool list. It will be changed to save the complete tool info.
I just need to add error checking and the tool functions and then I can release it.
UPDATE: Turned out to be relatively easy- it’s all working now. I just need to add some error messages for failures.
New Support Forum
I just got done adding a new support forum at http://www.grzsoftware.com/forum . Yahoo Groups was fine 3 years ago, but it’s looking pretty unprofessional to have it hosted there now. It’s also painful- for me at least- to browse through everything and keep up to date. Hopefully this new forum will be better for everyone.
It would help if readers here can go create accounts, log in, and poke around. If it seems to be working then I’m going to change the link on the website over and make it so no new posts can be added to the Yahoo group.
New Update
Run the Check for Updates command in 6908 and let me know how it works.

