Red lead primer — menie in Dutch — is an orange-red to red-brown primer intended to stop rust and timber decay. The traditional version owed that property to red lead pigment (lead oxide, Pb₃O₄). Because lead is harmful to health, lead-containing paint has long been off-limits for normal use; what you buy today is a lead-free primer based on zinc phosphate or iron oxide.
Types
| Type | Pigment | Status |
|---|---|---|
| Red lead | Lead oxide (Pb₃O₄) | Banned for general use; only found in old paint layers |
| Red oxide primer | Iron oxide, often with zinc phosphate | The standard lead-free primer for steel |
| Zinc phosphate primer | Zinc phosphate | Modern anti-corrosive primer, also water-based |
How to use it
Red oxide primer is a primer, not a finish coat: it must be overcoated, otherwise the layer chalks and weathers away.
Working on steel:
- Remove rust — wire brush, sand or blast back to sound, clean steel; loose rust destroys adhesion
- Degrease — use a suitable degreaser and let it dry
- Prime — two thin coats rather than one thick one; pay special attention to edges, corners and welds
- Topcoat — finish with a compatible paint after the specified drying time
On timber, this type of primer is still used to protect end grain and concealed parts, but modern wood primers and preservatives are usually a better choice.
Beware of old paint layers
Old red lead is still present on many steel railings, windows and structures built before the 1990s. Sanding or burning it off releases lead dust and fumes. Never dry-sand suspect old paint: have it tested, or leave removal to a specialist contractor with proper extraction and protective equipment.
Related terms
- Corrosion
- Steel
- Coating
- Galvanising
- Maintenance
- Weathering steel
Want to learn more about construction terms? Visit our knowledge base at fredsdiyplans.com.