Application Note 2.0: CNC Foam Cutting

IndustryApplicationChallenges
Manufacturing CNC Foam Cutting
  • Accurate multi-axis control
  • Multi-dimensional coordination between axes
Download PDF of this Application Note here.

Situation

EPS foam sculpting is a popular method for designing and producing high quality expanded polystyrene (EPS) foam core monuments, 3D signs, sculptures, and prototypes. The process starts when a thin, taut metal wire is heated to approximately 200°C. The hot wire vaporizes the foam just before any contact is made and cuts the foam into manageably sized blocks, consequently if this wire is fed too quickly, it could touch the foam and ruin the product. Once cut, the blocks are transferred to a CNC router where the blocks are carved into virtually any shape and detailed.

Problem

Increasing complexity of designs mean EPS sculpting machines need to be more accurate and reliable. Typically stepper motors are chosen to control axial movement, but inaccuracy and failures often lead to miss-shaped blocks and expensive downtime while the machines are tweaked. Since the accuracy of the cutting system is dependent on the precision of the motors used and the backlash of the drive system, motors used need to be accurate while having the ability to coordinate smooth motion across multiple axes.

Solution

One foam sculpting company chose four fully integrated SmartMotors on their CNC router: 2 on the x-axis, 1 on the Y-axis, and one on the Z-axis. SmartMotors communicated with each other through Animatics’ JenCNC software that combined CAD/CAM and motion control capabilities into a unique graphical user interface to coordinate the SmartMotors across three dimensions. The SmartMotor’s compact, integrated design allowed for an easy retrofit onto the existing machine and the reliability of the SmartMotor provided more accurate sculptures with little backlash.