Best Glue for Metal – Looking at the Best Metal Adhesives
This post may contain affiliate links. We may earn a small commission from purchases made through them, at no additional cost to you.
When dealing with the bonding of metals, there are a number of methods that come into play. Welding is certainly one of the most widely known methods used. Gluing metal is still unfamiliar to the home DIY user, for the most part, however, it is growing in popularity for applications in domestic and industrial sectors. Stick around, and the guide that follows will show you more about metal adhesives and their various application methods.
Table of Contents
- 1 What is Metal Glue?
- 2 Considerations for Choosing a Metal Adhesive
- 3 Pros and Cons of Metal Bonding
- 4 The Different Metal Adhesives in Overview
- 5 Considerations When Choosing the Best Metal Glue
- 6 Practical Applications of Metal Adhesives
- 7 Adhesive for Metal on Other Materials
- 8 Gluing Instructions for Metal
- 9 How to Glue Metal to Metal
- 10 Safety Instructions
- 11 Frequently Asked Questions
What is Metal Glue?
When discussing the various methods used for merging metal, welding is certainly the first to come up, but other ways like riveting are also used. Currently, bonding metal is a joining technique that is growing in popularity. When we join metals we are confronted with a unique set of obstacles, so generally a highly durable and effective adhesive is needed. There are certain considerations to take into account when using specialized metal adhesives, so the following information will help familiarize you and assist you in your choices.
Considerations for Choosing a Metal Adhesive
When considering the use of a metal adhesive, certain aspects may need your attention. Give these questions some thought before deciding which metal adhesive to use, as they cover factors crucial for effective metal bonding.
- When joining metals, especially of two different types, be sure you understand the characteristics of each surface. For this purpose, will also require a specialized metal glue product.
- What qualities does the surface you are bonding possess? Aluminum, for instance, requires the surface to be repeatedly oxidized. Certain types of metal have different textured surfaces and some may require smoothing out for effective adhesion,
- What size is the area and what are its structural properties?
- How long will the glue need to set and what conditions are present during the process?
- What environment will the bonded metal be used in and how much weight will it need to support effectively?
- Are the materials supplied with pre-coated surfaces?
Pros and Cons of Metal Bonding
Metal adhesive bonding has several characteristic benefits which the home DIY user should consider:
PROS
CONS
- As metal adhesive bonding does not penetrate the metal’s surface, the bond is not as durable or steadfast as a joining method like screws, rivets or welding would produce.
- Numerous adhesives and primer products require you to wear safety equipment when applying them, in compliance with typical safety standards.
The Different Metal Adhesives in Overview
For a metal adhesive product to meet high-quality standards, it must have certain essential characteristics:
- Effective resistance to heat and adverse weather
- Resistance to impact shock
- Allows file and drill work
- Chemical resistance
- Resistance to oxidation common to metals over time
There are numerous metal adhesive products available offering these qualities:
- Epoxy-based metal adhesive is formulated with epoxy resin. It is commonly used for costume jewelry manufacturing and in the processing of wood. Epoxy adhesive is also well suited for the bonding of metal.
- Adhesive products formulated with the characteristically resilient substance, polyurethane, provide several user benefits. PU adhesives offer durability in exterior applications, as they are both UV and water-resistant, and not prone to yellowing.
- Super glue products are commonly used household items, well-suited for with most adhesive bonds. While they offer an incredibly rapid drying permanent bonding solution, superglue is mostly suitable for covering very small regions or fixing irregular items like chipped crockery.
Another difference between one and two-component adhesive types is that singular compound adhesive products can also be used for sealing and filling applications. These hybrid adhesive types are more readily applied than dual-component formulas and offer more elasticity when they are set. These are especially well-suited for the bonding of iron, allowing for its specific thermal reactivity and expansion properties.
Epoxy Resin-Based Adhesives
Epoxy resin formulated adhesives offer a high durability solution for joining metals. These dual-component adhesives require mixing before application. Although you can mix and measure the formula yourself, there are also dual-chamber cartridge products that mix during application, for your convenience.
There is a wide range of different applications for epoxy resin adhesives, so each product has its own characteristics best suited for its specific purpose. Some adhesive products may dry slowly or rapidly and produce a high elasticity or a non-flexible bonding solution when they set, depending on their particular formula.
Additives like colorant or filling products can also be combined and used in conjunction, but are usually available in a black, grey, or transparent finish. These are well suited to load-bearing due to the durability and shock resistance, as well as being able to withstand extreme temperatures. Specialized epoxy-based adhesive types are especially well suited for use with non-ferrous metals, which are usually problematic.
- Strong, permanent, fast, and gap-filling glue for multiple surfaces
- Best for tough repairs requiring a durable bond and solvent resistance
- Dries clear, sets within 5 minutes, and is ideal for clean, easy finishing
Liquid Metal Based on Epoxy Resin
Bonding stainless steel and other heavy metals require a strong and extremely durable adhesive. This is available as a product called Liquid Metal from Petec. It resists temperatures of 120° C and also serves as a filler or sealant. This makes it an extremely versatile repair solution for numerous types of materials. It is extremely effective for joining cast iron, aluminum, stainless steel, and numerous different alloy types.
- A welding alternative two-part epoxy system
- Steel reinforced for serious tensile strength
- Easy to use over various applications
Polyurethane Adhesives for Bonding Metal
As a permanent metal repair solution, polyurethane adhesives are well suited for home use. This type of adhesive is ideal for exterior application due to its effective resistance to heat, UV-rays, and water. The formula sets rapidly and remains relatively pliant over time, and also allows painting, varnishing, or mechanical treatments once dry.
- Incredibly strong and versatile glue that can bond to many surfaces
- Best for tough repairs on dissimilar surfaces, both indoors and out
- 100% waterproof and won't break down when exposed to elements
Superglue
Superglue products produce an instantaneously high-durability join, even when used on metals. Should you be repairing or joining metal items that are small and intricate, then superglue is a great option. As the setting phase is so short, it limits the application to suit only single-surface bonds effectively.
- No run control gel formula that is great for use on vertical surfaces
- Gorilla tough anti-clog cap helps keep glue from drying out
- Specially formulated for increased impact resistance and strength
A Durable Solution: Wrought Metal
If you’re planning on joining stainless steel or metal types that require an extremely durable bond, epoxy putty is the right option for you. QuikSteel modeling clay comes highly recommended as one of the best sealing and bonding adhesives available, and it also offers a straightforward application procedure.
As a plus, this product is well-suited for quick repair jobs like an on-site bicycle repair. The product allows you to press and shape it around the join and, as it offers high durability adhesion, it can be used to fix a multitude of materials. Once the wrought metal has set properly, it can be simply finished with additional tools.
- A steel reinforced epoxy putty stick
- Easy to use and works on multiple metal surfaces
- Extremely durable 900 PSI strength
Considerations When Choosing the Best Metal Glue
Deciding on which metal adhesive is the best for your purposes is entirely dependent on the specifics of your repair job. You may find a simple glue product at your local hardware store that does the trick perfectly for your purposes. The choice isn’t about right or wrong, but rather which product is the best suited and most cost-effective solution.
Bond Time
Start by assessing the application method and how much time is required. Epoxy-based metal adhesive products and superglues have specific preparation, application, and setting times. When a metal glue product requires 48 hours to set, but you need assembly in 24 hours, you must select a more rapidly setting adhesive. Be sure that in doing so, this choice will not compromise or decrease the quality or durability of the joining.
Mechanical Challenges
Next, we can evaluate the metal join in terms of its flexibility and shock resistance. Your choice of metal adhesive will depend on the nature of mechanical forces present, the impact or vibration the bond will endure, and the level of pressure or weight exerted upon it.
Element Resistance
Your choice of the best glue for metal will also be affected by environmental factors. When used outdoors, the bonded metal may endure extreme temperatures and weather conditions, as well as being exposed to dust and dirt over time. So take note when selecting a metal adhesive.
Chemical resistance
As with environmental degradation, exposure to chemical agents such as acid, gasoline, or solvents can damage or corrode your metal bond over time. If the joined metal is situated in a factory, gas station, or warehouse where contact with chemicals may be a factor, then your metal adhesive will need to compensate for this.
Amount of Glue Required
Make an assessment of the joining work needed, as this will give you an idea of what area you need to cover. This will determine the quantity of adhesive necessary and what your expenditure will be.
User-Friendliness
The application procedure has many variables for adhesives and the purpose each product is designed for. Some adhesives may require concise mixing, some will need you to wear protective equipment when working with them, due to their chemical formulas. The fluidity of the adhesive and its drying process are also factors that contribute to the overall ease of use.
Practical Applications of Metal Adhesives
A metal adhesive is perfect for high durability bonding applications, in a range of different situations. It may be useful to add superglue to your puncture repair kit, so when you are out cycling you’ll be able to easily see to your bike’s metal repairs should you need to.
A decent metal adhesive will also be well suited for use with motor vehicles, like repairing the cracks on your car’s bumper for instance. Certain products will provide not only metal bonding but plastic as well, making them perfect adhesives for the job. When using metal glue on your car, you must take the following qualities into account:
- Gasoline or break fluid resistance
- The level of heat resistance
- Resistance to motor oil
The other characteristic aspects will vary from product to product. Some adhesives offer flexibility, while others may be more durable. Repairing your exhaust presents very different requirements to your side mirror, so ensure you take the specific area of application into account before repairing it.
Metal adhesive can also save the day at home, for the repairing of a child’s broken toy. These mishaps are part of growing up, but at least you may avoid the catastrophe and bring a smile back to an unhappy face. These adhesives offer many other uses than simply the bonding of metals.
Adhesive for Metal on Other Materials
Epoxy resin-based adhesives are suitable for a range of uses other than just metals. They will effectively bond cast iron and other metals, but they are also highly effective with other materials such as:
- Wooden items
- Glassware
- Porcelain and ceramic items
- Stone
- Several different plastic types
It will be beneficial to research the various kinds of surfaces. If, for instance, you aim to bond metal to wood, you might assess the porous quality of the wood and the even surface of the metal.
Gluing Instructions for Metal
The guide that follows provides details of the processes involved when working with metal adhesive products.
Preparatory work
To ensure the effective adhesion of the joining procedure, the surfaces you intend to bond must be prepped. This is essential for metal bonding, as it is likely to experience pressure from mechanical force and heat. Should the adhesion of the metal glue become diminished from insufficient cleaning of the surfaces, the join may not hold effectively. The surfaces must therefore be free of the following materials:
- Any type of oil or grease
- Traces of dirt or dust
- Any residue of previously applied sealants or adhesives
- Presence of grate
We suggest wearing protective gloves to avoid touching the adhesion surface with your fingertips. The presence of any oil from the skin will reduce the adhesion. Any rust should be completely removed prior to applying the adhesive. Grinding or sandblasting can free the surface of rust, but it will create dust in the process which will also need to be cleared. To optimize the bonding capability of the surfaces, they can also be grinded or sandblasted. Completely remove any traces of dust, dirt, or grime from the surface, as this will reduce the adhesion considerably.
There are a multitude of products with which to remove oil, grease, metal-to-metal, or any sealants. An HG-Cleaner will be well suited for this, which is also generally a recommendation from the manufacturers of metal adhesive products.
The Bonding Process
Give the surfaces a chance to dry properly after they have been completely cleaned. While following the instructions carefully, we can now apply the specialized metal adhesive. You may need to coat one or both bonding surfaces and allow the flash-off duration, depending on your choice of adhesive.
After the application, the two surfaces are then fixed and held together, depending on the type of adhesive applied. Epoxy-based metal adhesives require pressure exerted upon the join for up to an hour. Acetone can then be used for removing any excess adhesive present.
Curing and Loading the Joints
Pay attention to the product instructions for details about the time it takes the adhesive to set completely. Superglue dries incredibly rapidly, while epoxy adhesives may require 24 hours to set. Should you have any doubts, simply let the joins dry for a longer spell. Once this is complete they can hold weight and be finished with machine power tools.
Rework
Once the adhesive has set completely, the join can be finished, either by sanding and drilling or by applying a paint or lacquer coating.
How to Glue Metal to Metal
By carefully preparing the substrates, we can make sure of an effective metal to metal glue bond. The surfaces will require thorough cleaning, to remove any traces of paint, rust, or corrosion by scraping or sanding the areas. You can then use a cloth or paper towel doused with a degreasing agent or detergent to get rid of any dirt, dust, oil, wax, or grease. You can roughen the adhesion surfaces using sandpaper with a finer grit factor. Place the surfaces together to ensure the surfaces align evenly, being mindful not to touch them with your fingers.
Follow the product directions for applying the adhesive. Metal to metal glue products will generally suggest working either outdoors or in an area with adequate airflow and wearing a respiratory device in the presence of any fumes during the process.
Safety Instructions
Safety is crucial when using metal adhesive products, and even more so with epoxy and polyurethane-based adhesives. Your workspace should have decent airflow and you will need to wear a protective respiratory device in the presence of fumes and vapors. Safety gloves will also protect your hands from contact with the adhesive. Ensure the gloves are manufactured from nitrile rather than PVC or cotton, as this is far more chemically resistant.
Take careful note of all product warnings before using them. Should the adhesive touch your eyes or if you inhale fumes, rinse your face with warm water and seek a medical practitioner without delay. Make sure to keep the ingredients list from the adhesive with you to inform your doctor.
Frequently Asked Questions
What’s the Best Glue for Metal?
This is completely dependent on the specifics of the application, such as the type of metal and its purpose, the environmental and mechanical forces in effect as well as the presence of any chemical agents that may come in contact with the metal bond.
Which Metal to Metal Adhesive is the Most Durable?
Epoxy-based adhesives offer the highest durability. They often require mixing the adhesive with a hardener in equal amounts and then apply this mixture to the surfaces with a specialized implement.
Does Super Glue Work on Metal?
Super glue products are perfect for metal-to-metal glue bonding, and with other types of materials too. Ensure the surfaces are clean and make use of a clamp to join the surfaces evenly as they dry.
How Well Does Metal Adhesive Hold?
When used with the appropriate substrate, the best glue for metal provides a bond with lasting durability. This will not produce a bond as strong as a welded join though.
How to Bond Metal?
Any large gaps between the two surfaces need to be evened out to ensure effective adhesive bonding. Next, remember to remove all traces of oil, grease, paint, or dirt prior to the application.
Selecting the correct metal adhesive for your purposes can be difficult, with many variables to take into account. The application process itself is rather straightforward when you are using the right adhesive. We hope the methods outlined in this guide will help you to achieve perfect results!
