Grinding Basics: An Introduction to Grinding Principles
An overview of the fundamental topics covered in our Grinding Basics workshop, designed for engineers, machinists and production teams who want to get more out of their grinding operations.
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1. Abrasives 2. Bonding Systems 3. Coolant 4. Cylindrical Grinding I 5. Cylindrical Grinding II |
6. Grinding Burn 7. Machine Requirements 8. Q Prime & G-Ratio 9. Surface Grinding 10. Truing & Dressing |
Abrasives
Superabrasive wheels use either CBN (Cubic Boron Nitride) or Diamond as the cutting medium. Choosing the right abrasive for your workpiece material is the most fundamental decision in wheel selection. The wrong choice leads to rapid wheel failure, poor finish or workpiece damage.
CBN is the abrasive of choice for ferrous materials like steel, cast iron and hardened alloys. Diamond is used for non-ferrous materials, carbide, ceramics and superhard materials like PCD and PCBN. Grit size, concentration and abrasive quality all play a role in the final result.
Abrasive types and properties · Grit size selection and its effect on finish and removal rate · Industry standard size charts · How to read a wheel specification marking
Bonding Systems
The bond holds the abrasive grains in place and controls how the wheel wears. SuperAbrasives manufactures wheels in vitrified, resin, metal and electroplated bond systems, each suited to different applications, machines and production environments.
Selecting the wrong bond is one of the most common reasons a CBN wheel underperforms. The right bond depends on your material, machine power, removal rate target and dressing method.
Vitrified, resin, metal and electroplated bond characteristics · When to use each · The Maximizer bond system for lower-HP machines · Bond hardness and its effect on performance
Coolant
Coolant is one of the most underestimated variables in grinding. Poor coolant strategy is responsible for a large percentage of grinding burn, inconsistent finish and premature wheel failure. Fixing coolant is often the fastest way to improve a struggling process without changing anything else.
Coolant removes heat from the grinding zone, lubricates the wheel-workpiece interface and flushes swarf out of the contact area. Each of these functions requires a different approach depending on your bond type, wheel speed and material.
Coolant types and when to use each · Flow rate and pressure requirements · Nozzle design and positioning · Filtration requirements for CBN grinding · Common coolant mistakes and how to fix them
Cylindrical Grinding I
This session covers three of the most common cylindrical grinding configurations in production manufacturing: centerless grinding, camshaft and crankshaft grinding, and internal diameter (ID) grinding. Each has its own setup challenges, wheel requirements and optimization levers.
Centerless grinding is widely used for high-volume OD grinding without fixtures. Cam and crank grinding are among the most demanding automotive applications. ID grinding presents unique challenges around wheel stiffness and heat management.
Through-feed vs plunge centerless setups · Cam lobe and journal grinding requirements · Crankshaft pin and main bearing grinding · ID grinding wheel selection and setup
Cylindrical Grinding II
Building on the fundamentals, this session covers OD plunge, traverse, peel, face and slot grinding, the full range of cylindrical grinding modes used in production and job shop environments.
Each mode has its own approach to infeed, wheel selection and dressing strategy. Understanding the differences lets you select the right process for a given part geometry and production requirement.
OD plunge and traverse grinding · Peel grinding for complex shaft profiles · Face and slot grinding considerations · Choosing the right mode for your application
Grinding Burn
Grinding burn occurs when heat in the grinding zone exceeds the material’s thermal tolerance, causing metallurgical changes in the workpiece surface. A burned part can look perfectly acceptable while its surface hardness and integrity have been compromised.
Understanding what causes burn, how to detect it and how to prevent it is essential for anyone responsible for ground components in critical applications like automotive powertrains, aerospace and medical devices.
Types of grinding burn and what each means metallurgically · Root causes · Detection methods including nital etch and Barkhausen noise · How CBN reduces thermal damage vs conventional abrasive
Machine Requirements
The grinding machine is the foundation of your process. A CBN wheel will only perform as well as the machine it runs on. Spindle condition, power, speed range and overall rigidity all directly affect what the wheel can achieve.
Many underperforming CBN processes are actually machine problems, not wheel problems. Evaluating your machine before specifying a wheel saves time and avoids misdiagnosis.
Spindle power requirements for CBN · How to assess spindle integrity and runout · Machine rigidity and its effect on chatter · What machines work well with the Maximizer at lower HP
Q Prime (Q’) & G-Ratio
Q prime and G-ratio are the two metrics that matter most when evaluating grinding performance and economics. Q prime measures how aggressively material is being removed. G-ratio measures how efficiently the wheel is being used.
These calculations are often skipped in job shop environments but they are the language of production grinding and essential for making a business case for switching to superabrasive wheels.
Q prime definition and how to calculate it for your process · G-ratio definition and calculation · Using G-ratio to compare wheel economics · How to present the CBN cost case to management
Surface Grinding
Surface grinding produces flat surfaces and is widely used across aerospace, automotive, die and mold, and general manufacturing. The choice between conventional reciprocating grinding and creep feed grinding has a major impact on wheel selection, coolant strategy and part quality.
Understanding when and why to use each approach is a key skill for process engineers working with superabrasive wheels.
Horizontal and vertical spindle configurations · Conventional vs creep feed surface grinding · Wheel selection for surface applications · Common surface grinding problems and solutions
Truing & Dressing
Truing makes the wheel concentric and accurate to the machine spindle. Dressing opens the wheel face to expose fresh cutting edges. They are often done together but serve different purposes and require different parameters.
Over-dressing is one of the most common hidden costs in grinding. It accelerates wheel consumption without improving part quality. Getting dressing right can significantly extend wheel life and reduce cost per part.
Truing vs dressing and when each is needed · Rotary diamond dressers vs single point tools · Dress ratio and how it affects wheel topography · Dressing strategies for vitrified, resin and metal bond wheels
Bring This Training to Your Team
Dale Savington delivers this curriculum as an in-person or online workshop, customized to your machines, materials and applications.
