Glue for plastic to metal
To glue plastic to metal, there are different glues & adhesives available in addition to mechanical fixings. In this article we will look at how to stick plastic to metal together using glue & adhesive.
What is the best plastic to metal glue?
There are many different products that will stick plastic to metal, but to get a good strong long lasting bond, use the record breaking strongest Adiseal adhesive & sealant.
Why Adiseal is the best to glue metal to plastic
Adiseal adhesive & sealant is the best product at sticking metal to plastic together. In an independent adhesive strength test by Ultimate Handyman, Adiseal was the strongest. It was over 3 times stronger than the nearest competitor in the wood to metal bond strength test & also the strongest again in the metal to metal adhesive strength test. In fact it was so strong that the screws holding the metal sheet down started to rip out forcing the test on Adiseal to be stopped.
Strongest Adhesive Test Results
- Adiseal : 3123 psi
- SupaBond : 1115 psi
- Tec 7 : 1016 psi
- HB42 : 942 psi
- Loctite PL Premium : 873 psi
- Gorilla Grab Adhesive : 862 psi
- Bond It PU18 : 582 psi
- Bond It Saves Nails : 411 psi
Some of the other reasons why Adiseal is the best when trying to to bond plastic to metal:
- Adiseal is the record breaking strongest adhesive & sealant. It proved it’s the best in an independent adhesive strength test by Ultimate Handyman.
- Stays permanently flexible so it will absorb any vibration and allow any items to expand & contract without the adhesive becoming weak.
- Is waterproof so it is also suitable for use outdoors or indoors.
- Has very high gap fill properties.
- Has high initial grab meaning temporary supports may not be required while the adhesive cures. Adiseal Hi-Grab has even higher grab than the standard product.
- Is suitable for most plastics & all metal.
Problems with epoxy adhesives
There are several problems with using epoxy adhesives to glue plastic to metal. Listed below are the some of the problems of epoxy adhesives.
- Although epoxy adhesives might initially bond plastic to metal, epoxy adhesives are not flexible meaning the bond will become weaker over time. Air temperature & moisture changes cause items to expand & contract putting extra forces on an adhesive or glue. If the adhesive or glue is not flexible, it will become weak & brittle then eventually break. Metals are good heat conductors so are likely to expand & contract easily with temperature changes.
- Epoxy adhesives also come in 2 separate components which require mixing. To achieve optimum epoxy adhesive properties, the 2 components need to be the correct ratio therefore require careful measuring. They also need to be mixed thoroughly together. If these 2 are not done then the optimum properties of the epoxy may not be achieved.
- Epoxy adhesives have lower initial grab than Adiseal, meaning temporary supports will usually be required whilst the epoxy adhesive cures. This increases time & money with extra labour cost.
Problems with mastic adhesives
Just like epoxy, mastic adhesives also have many problems when being used as an adhesive to stick metal to plastic. Listed below are the main problems of mastic adhesives.
- The main problem with mastic adhesive is that the bond is weak in the 1st place. A mastic adhesive might be suitable at sticking light items indoors but will fail at more heavy duty applications.
- Another problem with mastic adhesives are they are not waterproof. This means they are not suitable for use where there will be water like bathrooms, kitchens or outdoors.
- Just like epoxy, mastic adhesives are not flexible meaning the already weak bond will become weaker over time.
- The initial grab of the mastic adhesive is also low meaning temporary supports will be required, increasing time & labour cost.
Problems with contact adhesives
Contact adhesives may be suitable at sticking light sheets to a surface but not suitable for more heavy duty applications. There are a number of problems with contact adhesives.
- Contact adhesives have low initial grab meaning temporary supports will be required until the adhesive has cured.
- Contact adhesives also has low gap fill meaning if there is a gap in certain places between the 2 surfaces of the items being bonded, the contact adhesive will not stretch between the 2 surfaces. This will create a much weaker bond as only in a few places where the surfaces are very close together will the adhesive successfully bond.
How to glue plastic to metal
When attempting to attach plastic to metal, preparing both the metal & plastic is vital to achieving a good strong long lasting bond.
Preparation of metal
To prepare the metal surface, make sure the surface is clean of any dust, grease, oil, paint, rust or any other dirt. UltraLube is an ideal penetrating oil & lubricant that can help in removing rust. Adisolve is the ideal product at removing oil, grease, tar & other stubborn deposits.
Preparation of plastic
To prepare the plastic surface, make sure the surface is clean of any dust, grease, oil, paint or any other dirt. Adisolve is the ideal product at removing oil, grease, tar & other stubborn deposits. Scratching the surface of the plastic will increase the surface area for the adhesive to stick to.
Applying the glue or adhesive between plastic & metal
Once both plastic & metal surfaces are clean, they are ready for the glue or adhesive.
Try to make sure there are no big gaps between the surfaces where the adhesive will be applied. If there are any big gaps then either cut or file down the surface of the plastic or metal so that they match closely when the plastic & metal are put together.
With Adiseal simply apply the adhesive to either the plastic or metal and push the metal and plastic together. As Adiseal has high grab, temporary supports should not be required but if the item does start to slide down then place temporary supports to hold the items in place until the adhesive has cured. Adiseal usually takes 24 hours to 48 hours to fully cure, with curing times increasing in colder temperatures.
Tip: If bonding plastic to metal where there is a chance of water, apply the adhesive in thin vertical strips. This allows any water to run down between the strips instead of building up on top of the adhesive. If there is a build up of water between the plastic & metal, in cold temperatures it will turn to ice which expands putting additional forces on the adhesive.
Glue plastic to metal with Adiglue
It is also possible to glue plastic to metal using our Adiglue. Although Adiglue is less brittle than super glues, it is still not as flexible or strong as Adiseal adhesive & sealant. Adiglue is a lot faster to cure than Adiseal, especially when used in conjunction with the Adiglue Activator. Instead of hours, Adiglue will glue metal to plastic in a few seconds when used together with the Adiglue Activator.
Stick metal to plastic with Adiseal Hi-Grab
The Adiseal Hi-Grab instant grab adhesive will also stick metal to plastic. It has a higher initial grab than Adiseal adhesive & sealant. We however recommend the Adiseal adhesive & sealant when attaching metal to plastic. The reason for this is because the Hi-Grab product is a very thick product. To push together the 2 items that need sticking together requires a lot bigger force if the Hi-Grab adhesive is between the items.
Sticking other materials to plastic
Both Adiseal adhesive & sealant & Adiglue will stick a lot more other types of materials to plastic. See the glue plastic page for more details.
Sticking other materials to metal
Both Adiseal adhesive & sealant & Adiglue will stick a lot more other types of materials to metal. See the bond metal page for more details.
Frequently Asked Questions
To attach plastic to metal, use the record breaking strongest adhesive, Adiseal. In an independent adhesive strength test, Adiseal was over 3 times stronger than the nearest competitor. Make sure both surfaces are thoroughly clean before applying the adhesive.
The best product to use is the record breaking strongest Adiseal. In an independent adhesive strength test, Adiseal was over 3 times stronger than the nearest competitor.
Adiseal will attach metal to plastic without screws. In an independent adhesive strength test, Adiseal was over 3 times stronger than the nearest competitor. Make sure both surfaces are thoroughly clean before applying the adhesive.
Adiseal adhesive & sealant will stick most types of plastic to all types of metals. Making sure both items are thoroughly clean will achieve the strongest bond. The strength of glue on plastic will depend on the type of plastic being stuck. There are many different types of plastics including PVC, ABS, polycarbonate, Plexiglas, perspex, acrylic, polyethylene, polystyrene & many others.