I find myself doing some rework to add features to some earlier revision parts for a prototype. I’m using custom fixtures to hold the parts for rework, but for the greatest accuracy- I would prefer to probe the arc radius (partial circular recess) that the pinhole is being cut nearest. The parts have a complete circle recess that is large enough to probe, but it is over 2" away. I’m doing that further away probe now and it appears to be giving accurate enough results due to the accuracy of the fixtures I made previously on our Tormach 1100S3, but I would prefer in the future to be able to probe arcs, etc. nearest the feature to take any slight tilt out of the accuracy limiting factors. There isn’t a single straight edge on the finished part, so that isn’t an option either. As I said, I have it under control, but I was surprised I had no PathPilot routine to probe an arc radius and automatically find the center of the radius. It would also be nice to probe a straight edge and rotate the entire coordinate system automatically to account for any tilt too.
With fixtures it is always best to make sure you have a way to put them in the machine with repeat accuracy.
If you are using a fixture plate from Saunders, then you can put locating pins on the bottom to have guaranteed position when putting it back in the machine and prevent any rotation. Besides making your setup more accurate you will find it makes it faster when you are changing jobs. Finally, I would put a feature on the fixture close to the component you are machining this way you can mount your component to the fixture plate probe the plate and you will have constant repeatability. While probing curves is great, I’ve used machines with 3D probing and found that it ended up introducing more problems than it was solving. Hope this helps.
A set of probing macros that include a 3 point bore routine that should allow you to probe your radius is a project that is on my plate (the 3 point bore routine I am writing allows you to specify the vectors of each point to probe). These routines are specificly intended for intergration in post processors, so they likely wont be built into the Pathpilot UI, but there’d be nothing stopping you from writing a quick program to run the macro.
The routines are likely 3-4 months out from being released at best, though.
If I understand your comment
It would also be nice to probe a straight edge and rotate the entire coordinate system automatically to account for any tilt too.
correctly then you should check out G68. here is an article on that
If you use the post processor available from Xoomspeed, you can do partial circle and partial boss probing - it’s included.
As I understand it- that’s a Fusion post-processor. Correct? I use SprutCAM.