It’s no surprise that concrete has been the epochal building material in the last century, but without metal, it wouldn’t have been as pivotal when it comes to modern buildings. Part of reinforced concrete metal is mainly used to create a building’s framework. That’s because metal is more versatile than it looks, which is why it’s been a popular building material, as it can be glued together, not just fastened. But to do the former, you need to choose the right type of glue, the same way you’d choose, say, between a drywall and an orbital sander.
Types of Metal-to-Metal Glue
Adhesive
When gluing two of the same metal surfaces, an adhesive is the best solution as it makes bonding two of the same surfaces rather easy. There are different types of metal-to-metal adhesives that are made for different occasions. You can get an adhesive metal-to-metal glue that sets slowly or quickly, or one that is transparent or opaque.
Epoxy
An epoxy is a more versatile option than an adhesive since it allows you to bind together two different types of metal surfaces. That’s because you can find epoxy glues in the form of two-part systems made of a resin and hardener. When mixed, these substances make for a strong bond between any type of surface, as long as you get the right combination of chemicals.
Super Glue
If you’re after the most versatile and easiest to use metal-to-metal glue, then you should go for a super glue. Keep in mind, though, that with it you can glue metal surfaces in your home with a super glue, but not for heavy-duty applications.
What to Consider with Metal-to-Metal Glue
Material
The type of metal you want to bond helps determine the type of glue you need for the job.
Steel, being an alloy of iron, is often coated and the bonding can be applied either before or after the metal has been coated, depending on the type of glue you go for.
Stainless steel, also an alloy of iron, has carbon added for improved corrosion resistance. Since the metal is already coated, you can pick from a larger number of metal-to-metal adhesives.
Aluminium is a light and durable material that is always alloyed as it improves its strength. Like stainless steel, since it is corrosion-resistant, aluminium can also be used with more adhesives than steel.
Flexibility
The level of flexibility of the metal also plays an important role in the type of glue you should get. More flexible materials dissipate energy more easily, while less flexible materials don’t, which is why you should match it with the glue’s flexibility. Otherwise, a metal-to-metal adhesive that is too rigid won’t be able to hold the two surfaces together when under tension.
Temperature
If the metal surfaces that you’re going to bond together are going to be exposed to heat, this means that the glue will be as well. Make sure that the glue you get can withstand the same temperatures the metal is exposed to.
Mechanical Stress
Another factor to keep in mind, alongside thermal resistance, is the mechanical abuse the metals will take. Be it to drill holes or to keep a part from moving, the glue should also be able to withstand the same amount of force, no matter how flexible it needs to be.
Corrosion
While the bond created by a metal-to-metal adhesive or an epoxy might not be corrosion-resistant on its own, it can help provide a protective layer between the two surfaces. This later can help improve the current corrosion resistance of the metals, but it depends on the type of glue you go for.
How to Use Metal-to-Metal Glue
Preparation
1. The first and most important step to glue two metal pieces successfully is to prepare them accordingly. Make sure to clean them and then dry them off any oil residue and dust, as this helps ensure proper adhesion.
2. You can use some sandpaper to roughen the surfaces so that the glue sticks even better. If you’re using an epoxy glue, you should prepare it by cutting the tip of the syringe that you’ll use to apply it with and then pulling back the plunger to let some air out.
Apply & Join
To apply the glue to the metal, you should wait 1 to 2 minutes after mixing the epoxy. Start by applying a little bit to both surfaces. To bond them together, after applying the rest of the glue, press the two pieces together and keep them like that for about 10 minutes. You can use a clamp or a weight for this.
Drying
Once the glue has had pressure applied to it for 10 minutes, leave it to dry for about 24 hours, as usually this is the time needed for it to fully cure. This period lets it get its full strength.
Cleaning
Before the glue cures, you should clean up the area where you glued the two metal pieces together. Get a damp cloth soaked in acetone to take off excess glue and if the adhesive has cured, you can remove it with a sharp blade.
