Toolpath

A toolpath is the programmed route that a printer head follows through space, defining the order, direction and speed with which material is deposited to form each layer.

Updated

A toolpath is the programmed route that a printer head follows through space, defining the order, direction and speed with which material is deposited to form each layer. It is produced by slicing a digital model and is normally exported as G-code or an equivalent machine instruction set. In concrete printing the toolpath carries not only geometry but also process parameters: travel speed, extrusion rate, and any pauses or retractions.

In practice

Continuous paths are strongly preferred, because every stop and restart leaves a visible seam and a weaker point in the wall. Path planning therefore tries to close each layer in a single loop, and to move the seam position from layer to layer so that defects do not stack vertically. Layer time is set indirectly by the toolpath: a long perimeter gives the previous layer more time to stiffen, a short one less, so a tall narrow feature can fail simply because the path returns too quickly. Corners are also a known weak point, since the head slows down there and deposits excess material unless the extrusion rate is compensated.

Related terms

  • Slicing — converting a model into layers from which the toolpath is generated.
  • G-code — the instruction language in which most toolpaths are expressed.
  • Print path continuity — the goal of avoiding starts and stops within a layer.

Related

SlicingSlicing is the conversion of a solid digital model into horizontal layers and machine instructions describing how each layer is to be printed.G-codeG-code is the numerical control language that tells a machine where to move, how fast, and what the tool should do while making the movement.Print path continuityPrint path continuity is the practice of printing each layer as one uninterrupted path, because every stop and restart creates a weak point.Parametric Design for 3D PrintingParametric design turns rules into geometry. How computational modelling, toolpath generation and print constraints shape 3D printed concrete elements.