CNC Carving of Topographical Mountain ranges

Snapmaker 2.0
2

First of all, Luban is only partly able to generate a 2-pass operation - there is a workaround, which is described in this guide: Multi-Pass Rotary Guide This is focussed on the rotary, but the idea of working with an offset is also OK for flat carving.

However, this workaround has limits and imperfections - unfortunately the answer is always the same: If you want it done properly, you need to learn another software. Many work with the free version of Fusion 360, which is extremely powerful, but also has a steep learning curve. There’s other software out there, most of it rather expensive. It seems (no real personal experience honestly) that DeskProto with its hobbyist license is affordable and simpler to learn than Fusion.

That said, when I use multi-pass operations I make sure that the work origin is not milled away and is there as a reference. If this is not possible because there is no such location on the workpiece, then I’d recommend to have some other reference, e.g. a piece of the same wood, to adjust Z-height. Leaving the setting is only possible if you are able to ensure that the second bit has exactly the same height than the first, and I’d say this is nearly impossible. So here’s a sketch of the procedure I’d do if there is no possible reference point on the workpiece itself:

  • Install the first bit
  • Navigate to the work origin and save it
  • Note down the values for X/Y/Z - in case for whatever reason you loose the position, you’ll be able to find it again via the coordinates as long as the workpiece has not been moved.
  • Pick a reference - like another piece of the same wood, or, if you do not have it, anything. Place it on the wasteboard, and move the toolhead so that the bit touches the reference. Note down Z.
  • Remove the reference and run the roughing operation.
  • Install the second bit.
  • Move the toolhead to touch the reference again. Note down Z. Calculate the difference between last bit’s reference Z and this Z.
  • Move the toolhead to X/Y noted, and adjust Z by the difference between the two reference measurements. Set this as new work origin.
  • Run the second operation.

Have fun!