Metal Repair Gum (Epoxy Putty)
"Metal Repair Gum" is a common, non-technical term used to describe Metal-Filled Epoxy Putty. This is a highly effective, moldable adhesive used for emergency and permanent repairs on metal and other hard surfaces.
It is a specialized product designed to act as a cold weld—a repair that is often strong enough to replace welding or soldering in non-structural applications.
✨ Key Characteristics
The product is typically a two-part system that comes in a single stick format:
- Composition: It consists of an epoxy resin (the outer layer) and a hardener (the inner core), often fortified with steel, aluminum, or other fine metal powders.
- Consistency: It has a clay-like or putty-like texture, making it moldable and ideal for filling large gaps, cracks, or holes.
- Curing: Once the resin and hardener are kneaded together, they chemically react and harden into an extremely durable, rigid solid.
🔧 How It Works (The "Gum" Process)
- Preparation: The surface to be repaired must be clean, dry, and free of oil, grease, or loose rust. Lightly roughing up the surface (with sandpaper or a file) often creates a stronger mechanical bond.
- Mix: Cut off the required amount of putty from the stick. Knead it thoroughly by hand until the two colors (e.g., a dark grey outer layer and a lighter core) are completely mixed into a single, uniform color (usually metallic grey). This mixing action starts the chemical curing process.
- Apply: Immediately press the mixed putty firmly into the hole, crack, or onto the surface you need to repair or rebuild.
- Cure: It will start to set within minutes (usually 5-15 minutes, depending on the brand and temperature) and cure fully within a few hours (typically 1 hour to 24 hours).
- Finish: Once fully cured, the material is hard as steel and can usually be drilled, tapped, sanded, filed, and painted.
⚙️ Common Applications
- Automotive: Repairing cracks in engine blocks (non-pressure bearing), sealing leaks in fuel tanks, radiators, and exhaust systems (with high-heat formulations).
- Plumbing: Sealing cracks and leaks in metal or PVC pipes (some types even work underwater).
- Household/Industrial: Repairing stripped threads, patching equipment, fixing tools, and restoring metal castings.