Having difficulty with generating route from imported bmp

I have imported a bmp (drag and drop on to the grid). Blur = 0, Base = 15, Border = 0.
setup = CNC (generic any linuxCNC). I use mm for the machine.
First problems:

  1. Base does not seem to import in mm, as the stock I have is set to 15mm Z, but the imported file does not match the 15mm of the stock.
  2. I am using just plain black and white image, but I cannot select the depth for the imported file. Seems the black is always set to a depth of ~0.5mm?

Second problems:

  1. using Trace, I never get any toolpath. I was expecting to get some paths following the black lines of the imported image, but no setting i have tried will produce any paths (the output has a scroll bar on the bottom of the grid, but just has 0 - 1). Contour outputs some paths, but that is not really a good router setting.

Any suggestions for getting Trace to output paths that follow the black lines in the imported BMP?

Hi @Daniel_G and welcome.

I’ll have to revisit the image import code to see how units translate. It could be relative to the translated pixel density meaning 5 would be the equivalent of 5 pixels in Z. Will let you know.

For imported images with lots of gradients and contouring, the best operation is contour. This will follow the grid lines from the import. Tracing is better for lettering.

Hi, Thanks for the response.
I have tried contour, and it seemed quite inefficient and time consuming to run the tool across the stock multiple times where there is no cutting, which is why I was thinking trace would be a better option.

Without seeing your image / model, it’s hard to provide better guidance.