1. What is a Speed and Feed Calculator for Wood CNC?

Definition: This calculator determines optimal spindle speed (RPM) and feed rate (IPM) for CNC wood cutting operations.

Purpose: It helps CNC operators and woodworkers achieve efficient material removal while maintaining tool life and cut quality.

2. How Does the Calculator Work?

The calculator uses two fundamental formulas:

Where:

• \( RPM \) — Spindle speed (revolutions per minute)
• \( SFM \) — Surface feet per minute (material specific)
• \( D \) — Tool diameter (inches)
• \( IPM \) — Feed rate (inches per minute)
• \( IPT \) — Chip load (inches per tooth)
• \( Z \) — Number of teeth on cutter

Explanation: The first formula converts SFM (material cutting speed) to RPM based on tool diameter. The second calculates feed rate based on RPM, chip load, and tooth count.

3. Importance of Proper Speed and Feed

Details: Correct RPM and IPM settings prevent tool breakage, burning, poor finish, and inefficient machining while maximizing tool life.

4. Using the Calculator

Tips: Enter the material's SFM value, tool diameter, recommended chip load (IPT), and number of teeth. Typical wood SFM ranges: 400-1000 (softwoods), 300-800 (hardwoods).

5. Frequently Asked Questions (FAQ)

Q1: What's a typical SFM for wood?
A: Softwoods: 400-1000 SFM, Hardwoods: 300-800 SFM. Start conservative and increase as needed.

Q2: How do I determine IPT?
A: Consult tool manufacturer recommendations. Common range: 0.005-0.030" for wood.

Q3: Why does diameter affect RPM?
A: Larger tools rotate slower to maintain the same cutting speed (SFM) at their edge.

Q4: What if my machine can't reach calculated RPM?
A: Use maximum available RPM and adjust IPM proportionally (IPM = RPM × IPT × Z).

Q5: How does material hardness affect settings?
A: Harder woods require lower SFM and sometimes smaller IPT to reduce tool stress.