Want to learn everything you need to know about how to glue plastic back together? We’ll explain how to select the best adhesives as well as the methods to get a strong permanent bond in this handy guide.
The best way to glue plastic: The most common adhesives
There are so many types of plastic used in a wide variety of applications that it can be hard to know what type of glue to use to make repairs. Your choice of adhesive will depend on several factors. When wanting to know how to stick plastic together, the information below will help you make the best selection.
The most used adhesives for gluing plastic together are super glue, plastic bonder, and epoxy. Each of these has unique traits that make them the best choice in certain situations.
Super glue dries quickly and is very convenient to use for small repairs. In most cases, only a drop or two is needed and the precision tip makes it easy to place the glue right where you need it. LePage Super Glue Gel Control, for instance, is an excellent overall adhesive for plastics and most other common materials. It sets fast and holds stronger than most other super glues thanks to a special additive. It dries crystal clear and doesn’t need clamping.
While super glue will bond to most plastics, there are certain types that it will not adhere to, such as polyethylene (PE) and polypropylene (PP). Special plastic bonding systems are called for in such cases, such as LePage Super Glue All Plastics. The primer/activator prepares the surface to accept the adhesive. The glue sets in seconds without clamping and dries clear for an invisible bond.
Your other option for repairs is epoxy. This two-part adhesive excels when the parts of the item don’t fit together tightly, or you are joining plastic to an uneven surface. Epoxy is strong enough once cured to span gaps, fill in surface imperfections, and can even be drilled or machined as needed. Choose an epoxy formula designed for plastics. Try LePage Epoxy Gel – it bonds to most rigid plastics as well as metal, glass, ceramics, and wood. Once dry it can be sanded and painted.
Still unsure whether you’ve chosen the right adhesive? Read the manufacturer’s instruction to make sure you’ve got the best product for the job at hand.
How to glue plastic: Detailed instructions
We’ll now cover the basic instructions for how to use these common types of glue.
In each case, make sure the parts to be glued are clean and free of dust or oily residue. If the surface is smooth or shiny, lightly sanding it with some sandpaper will improve adhesion. Also, pre-fit the parts before adding adhesive to make sure they fit properly.
How to stick plastic together with super glue
- Apply a small amount of glue to one surface.
- Press the parts together and hold them still until a bond begins to form (usually less than a minute).
- Allow the glue to fully cure before using the item. This usually takes about 24 hours.
- Clean up excess wet adhesive immediately with a damp cloth or paper towel. Dried adhesive must be carefully scraped away with a razor blade.
How to glue hard plastic together with plastic bonder
Plastic bonding systems are usually a two-step process. An activator or primer prepares the plastic to accept the adhesive, creating a stronger bond.
- Clean and pre-fit the parts as above.
- Apply the activator to both surfaces and allow it to dry.
- Apply the adhesive and join the parts.
- Check the label for curing time and allow to fully cure before use.
How to glue plastic together with epoxy
The two parts of epoxy (resin and hardener) must be mixed before applying. Once mixed, you have a limited working time before it hardens. See the label for more details.
- Open the tubes and dispense equal amounts of the resin and hardener onto a disposable surface.
- Mix the epoxy thoroughly. The epoxy will become uniform in colour.
- Apply the adhesive immediately after mixing and press the parts together.
- Allow the item to fully cure before sanding, painting, or using the repaired item.
Remember to work in a well-lit and ventilated area. Avoid contact with the glue by wearing nitrile gloves and safety glasses.