Contrary to popular belief superglue is not always as super as it is made out to be and not every superglue is made equal. That £1 bottle you can pick up in your local discount store may make bold promises to stick everything it comes into contact with but the reality can be quite different, in essence with superglue you get what you pay for.
In fact superglues are really only suitable for relatively small jobs and that is because of the way they cure. Superglues, or cyanoacrylates as they are more technically known, cure with moisture from either the atmosphere or from the materials being bonded. This means that if you have a large surface area and you try a superglue the section in the middle won’t actually bond because there won’t be enough air and therefore moisture able to get to it.
Also superglues are really only suited to very smooth surfaces as they have little to no gap fill capability. This means if you have a rough surface such as brick then again superglue is not the best choice.
All of that said superglue and especially Bondrite’s range of cyanoacrylates which has been specifically formulated for industry can give you an incredibly strong bond between a wide range of materials in a very short time. They are also non-flammable and solvent free.
In terms of materials our superglues are excellent at bonding metals such as stainless steel, aluminium and copper, rubber such as neoprene, NBR and SBR, plastics (polymers) such as polycarbonate, PVC and ABS, ceramics, wood and leather. Most bonds grab very rapidly in less than 10 seconds but for the more complex bonds this may take up to a minute.
How to choose the right superglue
Superglue is a bit like Velcro in the way it forms a bond, so essentially the bond is made up from lots of little hooks and eyes which once linked together are really hard to pull apart. That said unlike Velcro superglue doesn’t like to be repositioned as the hooks and eyes break and thereby weaken the bond.
Consequently there are different viscosities (thicknesses) of superglue, the thicker the glue the more repositioning time it gives you but the slower the bond. The more viscous glues will also give slightly better gap fill capabilities but this is still less than 0.5mm.
Our B200 is a very low viscosity glue particularly suitable for bonding plastic or rubber (EPDM) parts, where very fast fixing is required.
B300 is a low to medium viscosity glue which can be used for virtually any type of fastening job and contains a catalyst to help it cure more quickly even though it is thicker.
B400 has been specially formulated to achieve the strongest possible bond between rougher or irregular surfaces, on most metals, plastics or rubbers. It is normally used for mitre joints in kitchen cornices to give a little more positioning time.
B600 is our most viscous glue to give the best gap fill capability possible on rough and irregular surfaces.
If you need more time for repositioning but don’t want to have to wait for the B400 and B600 to cure then an activator is a great option to bring the curing time down. That said you have to be careful when spraying the activator as it is important to only spray one of the two surfaces. The superglue is then applied to the other surface and the two surfaces brought together. Activators can slightly weaken the final bond but this is generally less than 10% so it is a trade off between loss of strength and time saved.
How to get the best bond
- Make sure the surfaces to be bonded are clean and dry (preferable to solvent-wipe plastics and rubber, and to acid-treat metals).
- Dispense a drop or drops to one surface only. Apply only enough to leave a thin film after compression.
- Press parts together and hold firmly for a few seconds. Good contact is essential. An adequate bond develops in less than one minute. (Maximum strength is achieved in 24 to 48 hours).
HINT – blowing on a bond can actually help to speed up the curing process due to the moisture in your breath.
So don’t get stuck when choosing the right superglue for your job, it’s just a matter of viscosity and time.