I am designing an automated hot wire foam cutter for my project, and I am stuck on the computation for the most viable cutting speed of my design. The cutting tool used is a nichrome wire and the medium is a polystyrene board. How do I solve for the best cutting speed of a heated nichrome wire given the melting point of styrofoam boards have a melting point of 240 degrees Celsius, and the Styro board has a thickness of about half an inch.
Here is what I know, from my slight experience hand-cutting foam for model airplanes, and from things I've heard from actual experts:
- It varies with wire temperature, which, in turn, varies with applied voltage and cutting speed. So there's no one right speed, and things may change dramatically if you actively control for wire temperature.
- It varies with foam density (although usually the model airplane guys are using the lightest foam they can lay their hands on).
- You want to look for a range, because if you're cutting something tapered then the big end needs to go faster than the little end.
- To some small extent you can compensate for slow cutting by allowing for a bigger kerf -- a hot wire going slowly through foam melts more material, and you can sorta-kinda fix that.
I think you'll just need to experiment.