Shellac for Abrasives — Bond for Fine-Finish Grinding Wheels

Where shellac bonds are used

A grinding wheel is abrasive grain held together by a bond. Most wheels use vitrified (ceramic) or synthetic resin bonds. Shellac bonds, marked with the letter E in the standard wheel marking system, are a smaller specialist group. The bond is slightly elastic, so the wheel cuts cool and leaves a very fine finish.

Roll grinding (steel, paper and foil mill rolls)	Mirror-like finish on large rolls
Camshaft and precision finishing	Fine finish with low heat
Cutlery and knife grinding	Smooth edges and polished faces
Thin cut-off and specialist wheels	Elastic bond that resists chipping

How the bond is made

The wheel maker mixes shellac with abrasive grain, often with the shellac warmed or pre-ground, then presses the mix to shape and bakes it so the resin flows and binds the grain. The result depends on how evenly the shellac softens and flows. That is why wheel makers care more about consistency from lot to lot than about colour.

The right grade

Abrasive bonds are a technical use, so standard waxed shellac flakes or seedlac are normally used. Dewaxed or bleached grades are not needed. On the specification, wheel makers usually set:

• softening or melting range, and flow
• acid value
• impurities (alcohol-insoluble matter) and moisture
• particle size, if you buy ground resin

Store shellac cool and dry and use it in date order. Heat-aged resin flows less and can change how the bond cures.

How we supply abrasive makers

We supply shellac flakes, seedlac and button lac in 25 kg packs, with a batch COA from a NABL-accredited laboratory. Send your current specification or a sample of the resin you use when you request a quote, and we will match the grade.

Quick answers

What does bond code E mean on a grinding wheel? In the standard wheel marking system, E is the letter for a shellac bond. Other letters include V for vitrified, B for resinoid and R for rubber.

Do abrasive makers need dewaxed shellac? Usually not. Wheel bonds are normally made from standard waxed shellac or seedlac. The wheel maker's specification decides the grade.

What should a wheel maker put on the specification? Softening or melting range, flow, acid value, impurity (alcohol-insoluble) content and particle size if you buy ground resin. Consistency between lots matters most.

This guide summarises publicly available regulations and industry practice as of October 2026. Verify the current rules for your market and your own quality agreement before ordering. It is not legal advice.