1. What is a Speeds and Feeds Calculator for Plastic?

Definition: This calculator determines the optimal spindle speed (RPM) for machining plastic based on cutting speed and tool diameter.

Purpose: It helps machinists and CNC operators achieve efficient cutting while preventing material melting or tool damage.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( S \) — Spindle speed (revolutions per minute)
• \( v \) — Cutting speed (meters per minute)
• \( D \) — Tool diameter (millimeters)

Explanation: The formula converts cutting speed from m/min to mm/min (×1000) and divides by the tool's circumference to determine RPM.

3. Importance of Proper Speeds for Plastic

Details: Plastic machining requires higher speeds than metals to prevent material melting, but excessive speed can cause tool deflection or poor finish.

4. Using the Calculator

Tips: Enter the recommended cutting speed for your plastic material and the diameter of your cutting tool. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What are typical cutting speeds for plastics?
A: Varies by material: 100-300 m/min for acrylic, 150-400 m/min for PVC, 200-500 m/min for nylon.

Q2: Why is tool diameter important?
A: Smaller tools must spin faster to maintain the same surface speed at the cutting edge.

Q3: Should I adjust for feed rate?
A: Yes, feed per tooth should be adjusted based on material and tool type (typically 0.05-0.2mm/tooth for plastics).

Q4: What about different plastic types?
A: Softer plastics can handle higher speeds, while reinforced plastics may require slower speeds.

Q5: How does this relate to chip load?
A: Chip load (feed per tooth) works with RPM to determine feed rate. Both must be optimized for clean cuts.