What are the best practices for CNC reamer feed and speed?

1 What are CNC reamers?

CNC reamers are cylindrical cutting tools that have multiple flutes along their length. They are designed to enlarge and finish existing holes that have been drilled, bored, or punched. CNC reamers can improve the diameter, roundness, straightness, and surface finish of the holes, as well as remove burrs and chips. CNC reamers come in different types, sizes, and materials, depending on the application and the material being machined.

2 How to choose CNC reamers?

Choosing the right CNC reamer for your project depends on several factors, such as the type and size of the hole, the material and hardness of the workpiece, the tolerance and finish required, and the machine and tool holder capabilities. Generally, you should select a CNC reamer that has a slightly smaller diameter than the hole, a suitable flute geometry and coating for the material, and a shank that matches the tool holder. You should also consider the number of flutes, the helix angle, the cutting edge length, and the chamfer angle of the CNC reamer.

3 How to calculate CNC reamer feed and speed?

CNC reamer feed and speed are two important parameters that affect the quality and efficiency of the reaming process. Feed refers to the linear distance that the tool advances per revolution, while speed refers to the rotational velocity of the tool. To calculate the feed and speed values, you need to know the diameter and the number of flutes of the CNC reamer, as well as the recommended cutting speed and chip load for the material. The formulas are:

Feed rate (in/min) = Feed per tooth (in) x Number of teeth x Spindle speed (RPM)

Spindle speed (RPM) = (Cutting speed x 12) / (Diameter x pi)

You can also use online calculators or charts to find the optimal feed and speed values for your CNC reamer.

4 How to set up CNC reamer feed and speed?

Once you have calculated the feed and speed values for your CNC reamer, you need to set them up on your CNC machine. You can use the manual mode or the automatic mode, depending on your machine and software. In the manual mode, you need to enter the feed and speed values on the control panel or the keypad. In the automatic mode, you need to write a program code or use a CAM software that generates the code for you. You should also use a coolant or a lubricant to reduce heat and friction during the reaming process.

5 How to avoid CNC reamer feed and speed errors?

CNC reamer feed and speed errors can lead to a variety of issues, such as poor hole quality, tool wear, tool breakage, chatter, vibration, and overheating. To avoid these errors, it is best to use a pilot hole that is 90-95% of the reamer diameter, as well as a rigid and accurate tool holder and machine. Additionally, you should maintain a constant feed and speed throughout the reaming process, employ a peck cycle or dwell time to clear chips and prevent clogging, and use a smooth and gradual entry and exit of the reamer. Lastly, you should check and adjust the feed and speed values according to the material condition and tool performance.

6 How to measure CNC reamer feed and speed results?

In order to measure the results of your CNC reamer feed and speed, you should inspect the hole quality and the tool condition with various instruments and methods. This could include a caliper or micrometer to measure the hole diameter and roundness; a bore gauge or plug gauge to measure the hole tolerance and fit; a profilometer or microscope to measure the hole surface finish and roughness; a visual inspection or magnifier to check for burrs, chips, scratches, and cracks; and a wear indicator or comparator to check for tool wear and damage. Additionally, you should compare your results with the specifications and expectations of your project, making any necessary adjustments or corrections.