MM304 Screw-Top Mandrel – 3mm Arbor (3mm Shank)

This makes the MM304 particularly useful for engineering, jewellery, restoration, and precision polishing workflows where accuracy is more important than aggressive material coverage.

Choosing the Right Workflow:
Precision vs Stacking

When using 25mm radial discs, the ideal mandrel depends on the type of finishing process you are performing.

The MM304 is best suited to:

Because the arbor precisely matches the disc centre hole, it provides the most stable and accurate rotation possible.

If your workflow requires a wider abrasive face for blending or surface coverage, many users instead choose the MM503 mandrel.

Although the MM503 uses a smaller 1.6mm screw arbor, the discs are securely clamped using the screw head and washers, allowing users to stack multiple discs together.

This setup is commonly used for:

Some additional movement may occur compared to the MM304 due to the difference between arbor and centre-hole size.

Need a stacking setup?
View the MM503 stacking mandrel.

Beyond Radial Discs:
One Mandrel, Multiple Applications

Although widely used for 25mm radial bristle discs, the MM304 is also suitable for many other unmounted polishing and abrasive wheels with a 3mm centre hole.

Typical compatible products include:

This makes the MM304 a versatile workshop accessory for jewellers, restorers, engineers, clockmakers, and model makers.

Compatible Tool Types

The MM304 features a standard 3mm (1/8″) shank suitable for:

Always ensure the collet matches the mandrel shank size before operation.

Setup Tip

When mounting radial discs, ensure the bristle direction follows the rotation of the tool.

Because 25mm discs generate greater centrifugal force than smaller formats, always:

For users progressing through multiple grit stages, many workshops keep separate mandrels permanently loaded with different grades to reduce setup time.

Technical Specifications