Bonding metal to metal is not always easy. Smooth impervious metal surfaces offer little key for chemical bonding agents, while soldering and welding are unsuitable in small, delicate or heat sensitive areas and cannot bond large surfaces except in localised spots or edges.


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New adhesives address the problem, creating bonds that are often stronger than welding. Metal bonding adhesive is now often the method of choice, even in critical industries such as aeronautics. Here are the steps that ensure success.

Select the right adhesive

The most common mistake people make is thinking any glue will do. Most adhesives are only effective between certain materials, under specific conditions (temperature, moisture, light) and against specific kinds of movement (impact, sheering, vibration).

There are other considerations, including how quickly or slowly you need the adhesive to set, whether it can be released again, whether it needs to fill voids in the surfaces, whether it should conduct heat and electricity, and whether it should run into grooves or stay in place. Manufacturers list an enormous range of chemicals to match all possible combinations and it is often neither simple nor cheap to find the perfect one.


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Fortunately, new powerful adhesives from manufacturers such as are highly effective across a broad range of applications.

Clean surfaces thoroughly

A clean wet cloth with a minute amount of detergent will remove grease. Follow this with fine sandpapering to remove rust and oxides and to microscopically score the surface. It is pointless cleaning off grease and then touching the surfaces again, so consider wearing gloves.

Apply glue correctly

Follow the manufacturer’s instructions exactly, applying neither too much nor too little and leaving surfaces exposed to air or light for the specified time before pressing together. Many adhesives benefit from clamping while the agent hardens, typically for 24 hours.

Safety and removal

A well-ventilated area to work in is essential with some adhesives, and always advisable. Ensure you know whether your adhesive is safe to touch; for example, some organic solvents pass through the skin.

Removing overflow or splashes may depend on the glue, but even epoxy can usually be removed with vinegar and nail varnish remover (acetone). If the glue is nearly dry, try isopropanol; if it is already dry, you may need paint stripper and a heat gun.