Description
The platen assembly is one of the most heavily used components on any belt grinder. Every time you grind flat bevels, dress a surface, or finish flat bar stock, the belt is running against the platen face — and over time, that face wears. On the Radius Master, the platen sits behind the belt run between the drive wheel and the top tracking wheel, providing a firm, flat backing surface for controlled straight grinding passes.
A worn or damaged platen shows up quickly in your work: flat grinds develop a hollow or crowned profile, bevel angles become harder to hold consistently, and fine finishing passes leave uneven scratch patterns. In some cases the platen backing material can develop grooves or delamination from abrasive belt tracking issues or heavy use.
The Radius Master Replacement Platen Assembly is manufactured by NIROC to the original specification — correct material, correct dimensions, correct mounting geometry for the Series 2 belt head. It fits the RM-48 and RM48AE-VS directly, with no machining or modification required.
Signs your platen needs replacing:
- Flat grinds developing an unintended hollow or crown
- Uneven surface finish across the width of a flat grinding pass
- Visible wear grooves or depressions in the platen face
- Platen backing material cracking, delaminating, or separating
- Inconsistent bevel angles despite consistent hand technique
- Belt running hot in the platen zone due to increased friction from surface irregularity
Replacing the platen assembly is straightforward and is one of the most effective ways to restore flat grinding performance on an RM-48 that has seen heavy use.
Company Information
This is a genuine spare part manufactured by NIROC, the Australian company that acquired Radius Master Machinery in 2025. NIROC maintains a complete spare parts programme for the full Radius Master range — from wear items like the platen assembly and tracking wheel through to drive wheels and electrical components — ensuring that every Radius Master machine can be kept in full working order for its rated 20-year design life. Parts are available directly through NIROC (niroc.com.au) and authorised Radius Master dealers.
Features & Specifications
| Feature | Specification |
|---|---|
| Make | Radius Master / NIROC |
| Product Name | Replacement Platen Assembly |
| Part Type | Genuine OEM spare part |
| Compatible Machines | Radius Master RM-48 Series 2, RM48AE-VS Series 2 |
| Function | Flat belt backing surface for straight bevel and surface grinding |
| Belt Compatibility | 50 x 1220mm (2″ x 48″) |
| Installation | Direct replacement — fits Series 2 belt head without modification |
| Country of Origin | Australia |
Further Information
Platen Grinding — Why the Surface Matters
Unlike contact wheel grinding where the rubber surface has natural give, platen grinding presses the belt against a rigid, flat face. This makes the platen the most unforgiving station on the machine — any deviation from flat in the platen surface translates directly into the workpiece. A fresh, true platen makes flat bevel grinding significantly easier and more consistent, reducing the need for corrective passes and producing a cleaner, more uniform scratch pattern.
Platen Assembly vs. Platen Table (PT-48)
These are two distinct products. The Platen Assembly is an internal machine component — the structural backing surface inside the belt head that the belt runs against during flat grinding. The Platen Table (PT-48) is a separate work-support accessory that mounts externally and supports your workpiece during platen grinding. Both are available as genuine NIROC parts.
Scheduled Maintenance Tip
If you’re replacing the platen assembly, it’s a good opportunity to inspect the belt head for general wear — particularly the tracking wheel, belt tension spring, and any plastic or rubber components in the belt path. NIROC supplies all of these as individual spare parts, and a combined inspection during a platen replacement keeps downtime to a minimum.
