New Finishing Almost Done
Below is a shot of the almost-working finishing code. The big thing pictured below is that the threshold angle is now working (set to 20 degrees below)- I forgot that I would need to know the angle of contact with the cutter to determine the angle for both parallel and waterline finishing. This took another bunch of code and testing to get done. Also, the path linker turned out to be inadequate for the task and required a lot of changes to reduce the unneeded retracts. Luckily I’ve rewritten that so many times that it went really quickly.
Before I can release the new version I’ve got to add the code to find the correct forward step, the scallop height calculation that Randy mentioned, which should be no problem. Then I just need to make sure that mm/inch units are respected in the translation for the old ZMap code to the new code. These should both be pretty straight forward but there has been a lot of plumbing changed to get this code working so I’ll feel better after a lot of testing.
Filleted End Mills
I finally got the new code for filleted end mills working. I tried a number of ways to solve the line/torus intersection problem including one from an academic paper that seemed to just not work. I had hoped to solve the equations analytically but the math becomes unwieldy and round off errors due to floating point calculations make an iterative solution more accurate anyway. Below you can see an example of all of the work. It doesn’t look much different from a current toolpath and that’s a good thing. One difference though- this one takes every triangle in to account at each step. The current zmap-based approach can miss tiny features that fall between sampling points.
I just need to test the tapered filleted end mill and then I can move on to integrating it into the new finishing toolpath code.
Toolpath Update
The new ZMap-free finishing code is still in progress. I have only two types tool left to code, straight and tapered endmills with a corner radius. These are probably the most difficult because the math defining a torus is complicated.
If I can get this done within the next 3-4 days then I should be able to get the new finishing path done in the next few weeks. So far it’s not very fast but I haven’t had much time to dedicate to optimization. Hopefully any loss in speed will be more than offset by using less memory and only having to calculate the actual toolpath, not all the extra information that is currently calculated that is not directly part of the output path.