Author Topic: CB 1.0+ Linux: Wrong path calculation when 3D object, transformation matrix  (Read 1462 times)

Offline Earl Jay

  • Ewok
  • *
  • Posts: 10
    • View Profile
A bug that has been bothering me for a while is about wrong paths beeing calculated in z constant roughing mode.
I have a 3D Object (imported stl) that I rotate around in the 3D space using the transformation matrix ("Einheitenmatrix" in Germand CB).
The values in the matrix are then some crude numbers, not the 1s and 0s in all the fields.
When now calculating the Mops, it looks like a good path generation, but I get offsetts that can be subtle or machine destroying, so be careful!
So e.g. a complete path is 5mm apart in one direction or it might be 0.5mm. Both happens.
The bug is reproducible, because I get it alle the time with different 3D objects (always similar workflow-> import stl, rotate in space).

Now what has to be done as a workaround (and must not be forgotten, see above) is doing the align operation ("Ausrichten" in german CB) for it sets the tranformation matrix values back to 0s and 1s.
Then and only then the path generation works correctly and can be trusted.

CB is 64Bit Version.

Jens

Offline dh42

  • Administrator
  • CNC Jedi
  • *****
  • Posts: 7410
    • View Profile
    • Cambam V1.0 French Doc
Hello

Quote
Now what has to be done as a workaround (and must not be forgotten, see above) is doing the align operation ("Ausrichten" in german CB) for it sets the tranformation matrix values back to 0s and 1s.

Maybe you can try to "apply transformation" after the rotation has be done to set the matrix to "identity".

https://cambamcnc.com/doc/1.0/cad/transformations.html#apply-transformations

If you perform the rotation with the Nummove plugin instead to the transformation matrix, it automatically apply transformations.

https://cambam.pixelmaker.eu/download/plugins/plugin/transform/nummove_de.html#transform

++
David
« Last Edit: February 04, 2025, 20:49:49 pm by dh42 »

Offline Earl Jay

  • Ewok
  • *
  • Posts: 10
    • View Profile
Thanks David, I will test these methods.

Jens