GlueWise
More material pairs

Material pair

Metal to Metal

Best bet

Steel-reinforced 2-part epoxy

Fills gaps, tolerates high shear and tensile stress, resists oils and heat, and cures into machinable material.

Reviewed and adjusted by an editor.

Why this answer

  1. Smooth, dense, and non-porous — the glue sits entirely on the surface, so scuffing and degreasing matter more than which glue you pick.
  2. The strongest rigid bond on a scuffed, grease-free surface.

Preparation

Prep both faces the same way

Metal

Grind or scuff with 80-to-120-grit sandpaper to bare, bright metal. Degrease thoroughly with acetone or alcohol to remove cutting oils and grease.

Conditions

When the answer changes

Steel-reinforced 2-part epoxy is the standard for high-strength metal repairs, tool fixes, and load-bearing joints. Cyanoacrylate (super glue) is limited to small, tight-fitting decorative parts with no impact or shear stress.

Alternatives

What else works

  • Cyanoacrylate (super glue)

    Quick fix for small, perfectly flat metal parts with tight contact and minimal shock or shear stress.

  • Polyurethane

    Waterproof and more forgiving of movement than epoxy, but it has no pores to foam into on this side — scuff the metal and clamp the joint.

  • Construction adhesive

    For fixing a metal panel or trim across a wide area where a thick bead spans the hollows — not for a joint carrying its load through a small footprint.

  • Silicone

    Sticks well to clean metal and stays flexible and waterproof — a sealant around metal, not a joint that carries weight.

    Better when: Water immersion, Flexing or movement

  • Contact cement

    For facing metal with laminate, rubber, or leather over a wide area; degrease first, and expect it to soften if the metal gets hot.

  • Flexible fabric adhesive

    Only when the other side is cloth, and only on degreased metal — it holds a lining, not a load.

Avoid

What not to use

  • Avoid

    Spray adhesive

    Spray adhesive — the tacky film never hardens, so it creeps and slides on a smooth metal face.

  • Avoid

    Wood glue (PVA)

    Wood glue — it needs pores to soak into and peels straight off metal.

  • Avoid

    Solvent cement

    Solvent cement — it welds plastic by softening it, and metal never softens; the solvent flashes off and the parts come apart in your hands.

Guides

Repairs that involve this pair

Questions

Common questions

Can metal epoxy replace welding or brazing?
For brackets, machine housings, engine accessories, and non-structural tool repairs, high-strength steel-filled epoxy easily handles thousands of PSI of stress. However, for vehicle suspension, structural frames, and life-safety components, welding or mechanical bolts remain essential.
Why is degreasing with acetone or alcohol essential on metal?
Metals almost always carry invisible milling oils, rust inhibitors, or skin oils. Applying adhesive over oil bonds the glue to the oil film rather than the metal, causing sudden peeling under load. A quick solvent wipe restores true metal-to-adhesive contact.
Why does super glue snap off metal so easily?
Standard cyanoacrylate cures into a rigid glass-like film. Because metal conducts shock and vibration directly through the thin glue line, any twisting torque or sudden tap will shatter the brittle bond. Thick 2-part epoxy absorbs shock and distributes shear load.
What sandpaper grit should I use before bonding metal?
Use coarse 80-to-120-grit sandpaper or a wire brush. Polished or mirror-smooth metal provides minimal mechanical keying; coarse sanding scratches create micro-grooves that dramatically increase the bonding surface area.