---
title: "Which glue works on metal?"
description: "Two-part epoxy for anything structural, cyanoacrylate for small dry parts, and MMA where the surface cannot be properly prepared. The ranked options, the technique t"
url: https://atoneplace.net/which/glue-metal/
site: "At One Place"
---

# Which glue works on metal?

**Which glue works on metal?: Two-part epoxy for anything structural, cyanoacrylate for small dry parts, and MMA where the surface cannot be properly prepared.**

Metals have very high surface energy, so wetting is never the problem — what fails is the layer between the adhesive and the metal. Every metal carries an oxide, and on aluminium that oxide regrows within seconds of being abraded, so the bond is really adhesive-to-oxide and only as strong as the oxide's grip on the metal beneath. That is why abrading immediately before bonding, or using an etch primer or adhesion promoter, changes the result so much. The other trap is thermal expansion: aluminium expands roughly twice as much as steel per degree, so a rigid epoxy bond between them builds stress with every temperature swing and eventually cracks along the glue line. Design the joint so the adhesive is loaded in shear across a large area, never peeled from an edge.

## The options, ranked

*Ranked best-first for the stated job. The third column is why the others exist.*

| Option | Good at | Bad at |
| --- | --- | --- |
| Two-part epoxy | High shear strength, gap-filling, and available in metal-filled and high-temperature grades. The default for metal-to-metal. | Rigid, so it is poor in peel and cracks where two metals expand at different rates; softens above its glass transition, often 60-80 °C. |
| Methyl methacrylate structural adhesive | Tolerates oily and less-prepared surfaces better than epoxy and is far tougher in peel — used to bond car and rail bodies. | Strong smell, short working time, cartridge and mixer needed. |
| Cyanoacrylate | Instant, invisible, and fine for a small close-fitting part under shear. | Brittle, weak in peel, and degraded by moisture and heat over time. |
| Anaerobic retaining compound | The right product for a cylindrical fit — a bearing on a shaft, a stripped thread — because it cures where air is excluded. | Only works in a close-fitting gap between metal parts; useless as a general adhesive. |
| Soldering, brazing or welding | The correct answer for anything load-bearing, hot, or safety-critical. | Needs equipment, heat and skill, and distorts thin material. |

## Technique that changes the outcome

1. Abrade to bright metal with 80-120 grit or a wire wheel, then degrease with acetone or isopropanol
2. Bond within minutes of abrading, especially on aluminium
3. Maximise overlap area — doubling the overlap does far more than choosing a stronger glue
4. Clamp with light even pressure and leave for the full cure, which is often 24 hours, not the 5-minute handling time
5. For a joint that gets hot, check the adhesive's service temperature, not its cured strength

## What goes wrong

- Bonding anything structural, load-bearing or safety-critical — exhausts, tow points, brackets carrying weight
- Gluing over paint, plating or primer and expecting metal-strength results
- Loading the joint in peel, where even a strong adhesive unzips

> Compiled practical guidance rather than a published standard. Product formulations vary by brand and market, so read the label — and where the work is structural, electrical or gas, the regulations that apply where you are govern rather than anything here.

## Other glue and adhesive questions

| For | Use |
| --- | --- |
| Plastic | It depends entirely on which plastic — identify it first, because solvent cement is unbeatable on some and useless on others. |
| Polypropylene and polyethylene | Ordinary adhesives cannot wet these plastics at all. Use a polyolefin primer with cyanoacrylate, an MMA structural adhesive, or weld the plastic. |
| Wood | PVA wood glue for anything indoors; a water-resistant grade (Type I / D4) or polyurethane for anything that gets wet. |
| Ceramic and pottery | Two-part epoxy for anything that will be handled or loaded, cyanoacrylate for a clean break on a display piece — and neither is dishwasher-proof. |
| Shoes | A flexible shoe repair adhesive — polyurethane or a neoprene contact cement — never superglue, which cracks within a day of walking. |
| Fabric | A washable fabric adhesive or a fusible bonding web — and never superglue, which reacts with cotton violently enough to burn. |
| Glass | UV-cure glass adhesive for an invisible joint, clear epoxy where it must hold load, and neutral-cure silicone where it must stay flexible or wet. |
| PVC pipe | PVC solvent cement with its matching primer — and PVC, CPVC and ABS cements are not interchangeable. |
| Tiles | A cement-based thin-set in almost every case; ready-mixed tub adhesive only on small dry walls, never on floors or in showers. |
| Phone screens | A pre-cut adhesive gasket, or a flexible B-7000-type adhesive around the frame — superglue destroys screens and is the classic mistake. |
| Rubber | Contact cement for large flexible areas and rubber-toughened cyanoacrylate for small ones — but silicone and EPDM need a primer or they will not bond at all. |
| Outdoor and waterproof joints | Polyurethane or epoxy for rigid joints, MS polymer where the joint has to move — and check the water-resistance class rather than the word "waterproof". |
| Acrylic (Perspex, Plexiglas) | A solvent cement run into the joint by capillary action — not a tube adhesive, which will always look like a repair. |
| Concrete | Epoxy or a construction adhesive for bonding to it, and a chemical anchor resin — not glue — for anything that carries load. |
| Leather | Contact cement for a permanent flexible bond, or a leather-craft PVA to hold pieces while you stitch them. |
| Silicone | Effectively only more silicone, and even that needs a primer — and any silicone residue left on a surface stops everything else sticking too. |
| Paper | A glue stick or PVA for everyday work; wheat starch paste or methylcellulose for anything you want to survive — and never tape. |
| Foam | A foam-safe water-based adhesive or low-temperature hot melt — solvent adhesives dissolve polystyrene on contact. |
| Polycarbonate | A urethane or silicone adhesive is safest; solvent cements work but polycarbonate is unusually prone to stress cracking days later. |

## Common questions

### Which glue works on metal?

Two-part epoxy for anything structural, cyanoacrylate for small dry parts, and MMA where the surface cannot be properly prepared.

### What should I avoid?

Bonding anything structural, load-bearing or safety-critical — exhausts, tow points, brackets carrying weight Gluing over paint, plating or primer and expecting metal-strength results Loading the joint in peel, where even a strong adhesive unzips

## Related pages

- [Which glue works on plastic?](https://atoneplace.net/which/glue-plastic/)
- [Which glue works on polypropylene and polyethylene?](https://atoneplace.net/which/glue-polypropylene/)
- [Which glue works on wood?](https://atoneplace.net/which/glue-wood/)
- [Which glue works on ceramic?](https://atoneplace.net/which/glue-ceramic/)
- [Which glue works on shoes?](https://atoneplace.net/which/glue-shoes/)
- [Which glue works on fabric?](https://atoneplace.net/which/glue-fabric/)
- [Which glue works on glass?](https://atoneplace.net/which/glue-glass/)
- [Which glue works on PVC pipe?](https://atoneplace.net/which/glue-pvc-pipe/)
- [Which adhesive should I use for tiles?](https://atoneplace.net/which/glue-tile/)
- [Which glue works on a phone screen?](https://atoneplace.net/which/glue-phone-screen/)
- [Which drill bit should I use for metal?](https://atoneplace.net/which/drill-bit-metal/)
- [Which blade cuts metal?](https://atoneplace.net/which/blade-metal/)
- [Which paint should I use on metal?](https://atoneplace.net/which/paint-metal/)

## Sources

- Typical range compiled from manufacturer specifications — At One Place (/about/)