During turning operations, a single-point cutting tool is fed axially along the side of a rotating workpiece to remove material from it. Calculations use the intended cut diameter, cutting speed, and cutting feed, which ought to be selected under particular cutting conditions, such as the material of the workpiece and the tool's material.

The workpiece diameter may change during various turning processes, requiring spindle speed and cutting speed (SFM) adjustments. Usually, settings are determined for a single cut diameter, and the spindle or cutting speed is fixed while the other varies.

Calculating Turning Speed and Feed

What Is Turning Feed Rate (IPM)?

When referring to turning, the term "feed rate" denotes the speed at which the cutter is advanced against the workpiece. This rate is commonly given in inches per revolution (IPR) or millimeters per revolution (MPR).

Factors Influencing Turning Feed Rate

• Type of cutting tools used
• Required surface finish for milled parts
• Power at the spindle
• The rigidity of the machine and tool setup
• Properties of the material being cut
• Strength of the workpiece
• The cut width

What Is the Turning Spindle Speed (RPM)?

When a spindle, such as a milling machine, lathe, drill, or router, rotates, that frequency is measured in revolutions per minute as the spindle speed (RPM). The preferred speed is calculated by going backward from the desired cutting speed (SFM or m/min), the rate at the workpiece surface, and considering the cutter or workpiece diameter.

The process of CNC turning involves holding bars of material in a chuck and rotating them, so extra material can be removed to produce CNC-turned pieces that are precise in shape. n turning operations, the cut diameter is commonly used.

The Efficacy of Calculating Turning Speed and Feed

The spindle speed is derived from cutting feeds and speeds, and while it is one of the optimal cutting conditions for a tool, it must be adjusted if the condition is less than perfect. Typically, this involves reducing the spindle speed's RPM or modifying it to the proper value.

Although cutting speed is essential for some materials, such as stainless steel, which hardens easily during cold working before it becomes resistant to cutting, a wide range of spindle speeds can be used with certain materials. Since turning requires single-point cutting tools and all cutting occurs at one location, calculating the appropriate feed rate is straightforward.

It's, therefore, crucial to calculate the CNC turning speeds and feeds with a turning spindle speed and feed rate calculator and carefully control them to prevent overheating the cutter and workpiece. An inadequate feed rate or inaccurate spindle speed will result in poor cutting conditions.

An Outline of the Formula for Calculating

1. The spindle speed in the turning process is indicated by the RPM determined in the turning (lathe) speed and feed calculator, while the IPM shows the feed rate.
2. Cutting speed (SFM) is the rate at the workpiece surface expressed in surface feet per minute, regardless of the machining method.
3. The intended cut diameter, cutting speed, and cutting feed are used in the turning RPM and IPM calculations and should be selected depending on the unique cutting conditions, including the workpiece material and tool material.
4. The workpiece's diameter may fluctuate during various turning processes, requiring spindle and cutting speed adjustments.
5. Usually, settings are determined for a single cut diameter, and the spindle or cutting speed is fixed while the other varies.

The turning speed and feed calculator are excellent for calculating spindle speed and feed rate while cutting time in minutes for turning operations. Determining the correct speed and feed for lathe turning operations will help you save time and avoid errors.

Our turning calculator at SCTools computes CNC turning speed and feed, milling speed and feed, or drilling speed and feed based on your specifications.

If you have any questions about carbide cutting tools, end mills, drills, etc. be sure to reach out to us @ sctools.co/Home or call us at (877)737-0987. We help you machine better!