July 23, 2024
When it comes to structural bonding, you want to know that the bond will last even in the face of harsh weather, extreme temperatures, or frequent motion. While mechanical fasteners are the traditional means of bonding for many of these applications, adhesives have become more and more popular. We are taking a closer look at mechanical fastening versus adhesive bonding and comparing the two.
Mechanical Fasteners
Mechanical fasteners are general fixing like screws, nails, bolts, anchors, and rivets used to join together two components. They are used in a number of applications including structural bonding to hold together objects that may be exposed to a great deal of stress. Most mechanical fasteners create non-permanent bonds.
Adhesives
Adhesive is a term used to describe a non-metal substance used to bond two materials together at their surface. In layman’s term, adhesives are glues. They include a diverse collection of products designed for everything from arts and crafts to structural bonding.
Comparing Mechanical Fasteners vs. Adhesives
Traditionally mechanical fasteners have been used in structural bonding applications, but with the discovery of new adhesives with great strength and unique capabilities, some companies are turning to glues instead. We are looking at the pros and cons of mechanical fasteners versus adhesives to see which one might be best for your application.
Pros & Cons of Mechanical Fastening
Because mechanical fasteners are the traditional approach, they are sometimes considered the tried-and-true method of bonding. They are well tested in various applications and mostly successful. Generally, they are easy to install and because they have no cure time, they are ready immediately.
While they have some pros, many companies are replacing mechanical fasteners with adhesives for good reason. The biggest con to mechanical fasteners is their weight. When numerous are used, mechanical fasteners and their support systems (such as mending plates) can add a significant amount of weight to the final product. Especially for boats and automobiles trying to achieve great speed, this added weight can be problematic.
Along with more weight, mechanical fasteners can become corroded over time, are not fire resistant, and may not hold up in extreme temperatures. These flaws make them susceptible to damage and bond failure.
Pros and Cons of Adhesive Bonding
Some companies have made the switch from mechanical fastening to adhesive bonding. Compared to mechanical fasteners, adhesives are lighter weight. They are also usually resistant to corrosion, fire, extreme temperatures, certain chemicals, and more.
Another pro of adhesives over mechanical fasteners is their versatility. There are so many different adhesives out there. While some are made for more general purposes, others are designed with very specific applications in mind. You can often find similar products with various degrees of flexibility, resistance to chemicals, temperature compatibility, and more. This versatility can make adhesives more suitable for your application over mechanical fasteners.
One potential problem with adhesive bonding compared to mechanical fastening is the cure time. Adhesives need time to reach their full strength, but there are products with fast cure times available to minimize this issue. Some production lines may also need longer cure times depending on their setup. Another potential downfall is the application. The application of some adhesives may be more involved or require some training of staff, but some adhesives require minimal surface preparation.
Types of Structural Adhesives to Replace Mechanical Fasteners
If you are going to replace mechanical fastening with adhesive bonding, you need to make sure you are using the right adhesive. Not every glue is made for the job, but those structural adhesives that are can be a big difference maker.
MMAs 
Methyl methacrylate adhesives or MMAs are a type of two-part adhesive that cures when the two components are combined. They are known for their strong bonds as well as their great resistance to chemicals, heat, and vibrations. They also have a diverse collection of properties. For example, Infinity Bond MMA 500 is designed for plastics that other adhesives cannot bond to.
Acrylics
Acrylic adhesives are acrylic-based and can be used to bond together a diverse variety of different substrates. They are known for their great strength and durability. 3M DP8405NS is one popular choice made for general use. Not only is it impact resistant, but it also has a non-sag formula.
Epoxies
Epoxy adhesives are another type of structural adhesive that creates strong bonds. They generally have good temperature resistance and solvent resistance, and they are great for gap-filling and potting applications. The Infinity EP 100 epoxy is one such epoxy that is made for general use. It has a 5-minute open time and is resistant to chemicals, impact, shocks, and extreme weather.
Find the Right Product
If you need help finding a suitable adhesive to replace mechanical fasteners in your product, we want to help. Not only do we sell a diverse collection of products online, but also we have experts in the industry ready to answer all your questions. Just contact us today.
