How to glue metal to metal: the methods the pros use

There are several adhesives that can be used to glue metal to metal without welding. Considering the size of the project, the strength needed, and the conditions the part will be exposed to will help you choose the right type of glue.

For small surfaces and repairs, super glue is the easiest and most convenient. All super glues are not equal, however. You must use one that states it will bond to non-porous surfaces. An ideal glue will also state on the label that it bonds to metal.

For larger projects and especially when you need a bond with superior strength or gap-filling capability (due to a less-than-perfect fit), you’ll want to use epoxy. Epoxy is a two-part adhesive consisting of a resin and hardener that starts to set when mixed. See your label for setting time as different formulas will vary. 

Epoxy is extremely strong and resilient once cured. It is resistant to moisture, solvents, and temperature extremes and can even be sanded, drilled, or machined if needed.

Here’s how to glue metal together, step-by-step. We’ll use epoxy in this example, but using other adhesives will be similar.

1. Safety first: always work in a well-ventilated space and wear latex or nitrile gloves.
2. Prepare the surfaces. Ensure the surfaces are dirt and grease free and dry. Light sanding or using a wire brush to lightly roughen the surface will improve adhesion.
3. Pre-fit the pieces before mixing the epoxy.
4. If using a syringe-type applicator, cut the tips, turn the syringe upside down, and pull back the plunger. Then slowly press the plunger to expel the air.
5. Apply equal parts of resin and hardener to a piece of cardboard or another disposable surface. Use a paint stirrer or similar tool to mix the epoxy thoroughly for about one minute. Immediately clean the tips of the syringe and recap the tubes.
6. Apply a small amount of epoxy to both surfaces.
7. Press the parts together and hold them in position for about 10 minutes using a clamp or weight.
8. Allow to cure for 24 hours before use for maximum strength.

If you’re looking for the best alternative to welding two pieces of metal together, you need Loctite Universal Instant Epoxy Liquid 5 Minute. It’s a two-part system that, when mixed, quickly forms a rigid, high-strength bond to most types of metal. It dries transparent and can be sanded, machined, and painted once cured.

For smaller jobs and quick fixes, reach for Loctite Super Glue Control. This liquid glue is ideal for bonding to non-porous surfaces. It dries transparent and is highly resistant to moisture, shock, and temperature extremes.

If harsh conditions or vibration are a concern, you will appreciate Loctite All Purpose Extreme Gel. It stays flexible thanks to its exclusive Flextec formula. This powerful adhesive dries clear and withstands impact, vibration, UV light, and moisture.