What Are Epoxy Hardeners And Why Are They Used?

Epoxy Resin and Hardeners make up a versatile epoxy system that can be used for everything from basic, long-lasting repairs to the construction of high-performance composites.

When blended at the appropriate mix ratio, WEST SYSTEM Epoxy Resin and Hardeners will cure a high-strength plastic solid at 72°F. The resulting plastic adheres tenaciously to a wide range of materials, including woods, fibreglass and other reinforcing materials, and metals.

Select from a range of hardeners and additives to tailor your epoxy mixture’s handling characteristics and cured physical properties to suit your working conditions and specific coating or bonding application.

At their most basic, installation of epoxy floor coatings involves combining an epoxy resin with a hardening agent, which is then allowed to react with one another before being applied over a prepared concrete substrate.

The epoxy base resin may be clear or pre-pigmented depending on the specific system used. Some clear epoxy resins have compatible colour packs that can be added to tint the clear system at the job site.

Others employ special aggregate components to enhance specific performance properties, such as extra impact resistance, compressive strength or slip resistance. Examples of multicoloured elements include blended vinyl chips, and ceramic-coated quartz is a popular decorative addition.

How To Use Epoxy Resin And Hardener

Epoxy is a 2-compound system that consists of hardener and resin. These components are kept separately. Therefore, you have to mix these parts to start using this product.

This will trigger a chemical reaction, allowing the liquid resin to harden gradually. In most cases, the ratio of mixing hardener and resin is 1:1. However, you should read the manufacturer’s directions to be certain.

Before you apply this product, mix the hardener and resin completely until it has a uniform colour.

Measuring

The amount of resin you need for your project will depend on the type of craft you’re creating. To determine the exact resin you need, use a measuring cup. First, make sure the measuring tools are clean and dry. Next, measure an equal amount of hardener and resin, and then pour them into the mixing cup.

Mixing

After pouring the resin and hardener into the cup, stir the mixture thoroughly for 3 minutes.

Remember to scrape the sides and bottom of the cup several times as you go. This ensures that no unmixed epoxy is left stuck to the bottom of the sides of the container. But, more importantly, it ensures that the entire mixture catalyses.

Pouring

After mixing resin and hardener, you’ll have a working time of about 40 minutes. After that time period, the resin will harden and become too thick to spread. So, start pouring the resin mixture immediately after mixing.

Pour the mixture into the centre of your enclosure or mould.

The solution will automatically start to level. However, you can also use a spread to the solution to the edges. If you’re pouring the mixture into layers, let the previous layer cure fully.

Also, let the mixture reach room temperature before you pour additional layers.

Adding Dyes/ Glitters

The best thing about working with epoxy is that you can incorporate any additive to your pieces. For instance, you can add a powdered pigment, glitter, or a liquid colourant.

Regardless of the additive you choose, don’t put more than 6% of the total volume of the resin mixture. Remember, adding more dye to your mixture will affect its curing time.

To add dyes, add a few drops of dye to your mixture. Stir the mixture well until you get a uniform colour. Let the resin gel, then add glitter to the semi-cured solution for glitter.

Leave your piece for a couple of hours to allow the new layer set. After that, add more glitter and continue adding epoxy until the mould is full.

Pop-Out Bubbles

After pouring epoxy, air bubbles will start to rise to the surface.

The formation of these bubbles cannot be prevented. However, you can easily remove them from your mixture. To achieve that, apply a hot gun or an art resin torch over the resin surface in quick motions.

This will cause bubbles to rise to the surface and pop. Note, the heat source should be at least 10 cm away from the resin surface. Otherwise, your pieces will start to turn yellow or boil.

For stubborn air bubbles, use a toothpick for popping them. You can use this approach to remove dust and hair. Nonetheless, the surface should still be in its liquid state.

Finishing

If your pieces have healed fully, you can finish them. Here, you can use various finish tools like a hand block sander or 80- 120 grit sandpaper. Avoid using tools as they’ll remove too much resin.

Also, always wear a mask to protect yourself from the sanding dust. Afterwards, use acetone and vacuum to clean the dust.

The Function Of The Epoxy Hardener

On their own, epoxy resins are very stable fluids with relatively long shelf lives. Only when mixed with an epoxy hardener, can they cure properly. If applied onto a floor without the hardener, the resin would remain a near liquid indefinitely and could not transform into a durable flooring system.

Unlike paints, which rely on moisture evaporation to eventually harden into a thin film, an epoxy floor coating achieves its high-performance protective characteristics by undergoing a controlled chemical reaction between the carefully calibrated resin and hardener components.

Once the different elements of the floor coating are mixed, some may require “induction”, wherein they are left for 15-30 minutes to react to each other and allow the chemical process to take place before installation.

Still, other systems may have very short pot lives that demand the blended liquid be immediately “ribboned” out onto the prepared concrete substrate and spread since leaving the mixed product as a mass in the bucket would further accelerate the reaction speed.

When this does occur, the container and contents can become very hot and, in some cases, even emit smoke due to the extreme molecular activity. 

While individual components may be kept on the shelf for months or longer, once the epoxy coating and hardener have been mixed, the contractor may have only 15 minutes to install the combined material.

Multiple layers of the product may be installed, with the next coating being applied within a recoat window typically falling within the 4 to 12-hour range.

The method of application may vary based on the specific formula’s chemical makeup, thickness, and cure time.

With so much skill and knowledge required, it only makes sense that highly experienced specialty flooring contractors best install many commercial grade epoxy and other resinous floor coatings systems.

How Formula Impacts Performance

The amount and type of hardener needed to depend on the epoxy resin used. Do-it-yourself epoxy paints (different from true floor coatings) are often water or solvent-based.

They rely mainly, if not exclusively, on evaporation to harden and dry the final product.

These systems may require little or no hardener and often contain light-duty latex paints with added epoxy resin rather than true epoxy floor coatings.

True epoxy floor coating resin, though a liquid, contains 100% solids and relies on a compatible catalysing hardener to create the tightly cross-linked molecular structures that impart incredible strength, resilience and virtual impermeability into the cured film.

The type and amount of hardener used vary depending upon the specific product being installed. 

The term “epoxy” refers not to a single specific substance but rather to a wide range of prepolymer and polymer groups, and the type of epoxy used will impact the amount and type of hardener needed.

Manufacturers’ polymer scientists use the molecular weight of an epoxy floor coating formula and other methods to determine how much hardener is needed for an effective cure.

Different formulations have different characteristics, with some systems able to handle heavier loads, greater temperature fluctuations, higher levels of moisture, or increased chemical resistance.

Group Size Packaging

Epoxy resin and hardeners are packaged in three “Group Sizes.” For each container size of resin, there is a corresponding sized container of hardener. When purchasing epoxy resin and hardeners, be sure both containers are labelled with the same group size letter: A, B, C, or E.

Storage And Shelf Life Resin And Hardeners

Store epoxy resin and hardeners at room temperature. Keep containers closed to prevent contamination. Epoxy resin and hardeners should remain usable for many years with proper storage.

After a long period of storage, verify the metering accuracy of your epoxy pumps. Mix a small batch of epoxy (3 pumps strokes of resin and three pump strokes of hardener), stir thoroughly for one full minute and leave in the mixing cup.

The epoxy should cure a solid within the time frame listed on the hardener can for the temperature of your working environment.

This lets you know that your epoxy resin and hardener has not become contaminated and should be suitable for use on your project.

Over time, 105 Epoxy Resin will thicken slightly, so it will require extra care when mixing. Repeated freeze/thaw cycles during storage may cause crystallisation of 105 Resin. If this occurs, warm the resin to 125°F and stir to dissolve the crystals.

Hardeners may darken with age, but the colour does not affect cured physical properties. If clear finishing, be aware of a possible colour shift if you plan to use very old and new hardeners on the same project.

Dispensing And Mixing Epoxy Resin And Hardener

It is critical that you dispense epoxy resin and hardener at the correct ratio. Altering the amount of hardener does not control cure speed. Instead, it creates an epoxy mixture that can never fully cure and will have greatly reduced physical properties.

Epoxy can be accurately metered by volume or weight. Mix ratio information is on the hardener label and our technical datasheets. Our 300 Mini Pumps are hard to beat for the price when metering small amounts of epoxy.

One full pump stroke resin to one fuel pump stroke of hardener delivers the correct ratio. One pump stroke of each will total around one fluid ounce of epoxy. Depress each pump head fully, then allow it to rise to the top before beginning the next stroke.

To measure resin and hardener by volume, pour each component into a straight-sided container like our 805 or 806 Mixing Pot. Another method for metering by volume in a straight-sided container is to mark a paint stick at five parts 105 Resin and 1 part 205 Fast or 206 Slow Hardener.

For example, put a mark at 1.25″ for the resin, then another 0.25″ above that, put a mark for the hardener, for a total of 1.5″.

Pour the resin into a straight-sided container to the 1.25″ mark, then add hardener to the 1.5″ mark. This can also be done for 207 Special Clear and 209 Extra Slow Hardener but at three parts resin to 1 part hardener.

When mixing, stir the epoxy for at least two minutes to ensure it is thoroughly blended. In cooler temperatures, you will need to mix the epoxy longer. Scrape the sides, bottom, and inside corners of the container when mixing to ensure thorough blending.

How To Use Epoxy Resin And Hardener For Crafts 

Resin is a fun and interesting product for doing various craft projects. It allows you to create beautiful and personalised pieces with ease. You can even use it to make customised gifts for your friends and loved ones. It’s a great product to use on various crafts like coasters making.

Besides, you can use it to cast charms or unique pendants. Better still, it enables you to embed your favourite inclusions.

You can also add different colours to your pieces. Before you use epoxy for your crafts, there are some fundamentals you should be familiar with. They include;

Epoxy Resin Working Time And Curing Time

Using epoxy is a quite simple process. Nonetheless, there are simple precautions you need to take to ensure the safe use of the product. For instance, you should always have proper hand protection when handling epoxy.

More importantly, you need to understand that epoxy dries rather quickly. For this reason, it’s good to mix the resin and hardener in small batches. In other words, always mix as much hardener and resin as you’ll use in 10 – 30 minutes.

This duration is referred to as working time/ pot or gel time. Observing working time ensures that epoxy maintains adequate penetration and proper viscosity. On the other hand, the curing time refers to the duration taken by epoxy to harden completely.

In most cases, epoxy has a curing time of about 24 hours.

However, this will vary depending on type and room temperature factors. You need to note, though, that it’s only about 95% of the full cure after 24 hours. So to get the 100% full cure, you’ll need another 48 hours, giving you a total of 72 hours.

Supplies Needed When Using Epoxy Products

Epoxy offers endless possibilities! You can use various moulds to create multiple designs and embed different items. You can even mix it with different colours and pigments.

In this case, the supplies you need will depend on what you’re working on. However, you are some general supplies, regardless of the project you’re working on. They include;

• Resin and hardener
• 2 Mixing bowl or cup
• Protection hand gloves
• Wood stirring sticks for mixing
• Resin colour pigments
• Toothpicks
• Respirator mask
• Silicone mould
• Heat gun

If you’re overwhelmed seeing so many supplies to pick from here and there, here’s what we’ve got! This is a Beginner Kit for any Resin Art Lover who’s about to start their first project right away –

General Preparation And Precautions

Epoxy is certified as harmless and non-toxic. Yet, it can cause problems like skin irritation. Therefore, you should handle this product with care. On top of that, there are some precautions you need to take before you use it, and these include;

Wear Protective Clothing

Epoxy can irritate your eyes, skin, and respiratory system in its uncured form. Moreover, it is very sticky and difficult to remove from skin and clothing. To protect yourself from these harmful effects, put on protective clothing.

This includes wearing hand gloves and protective clothing to cover your entire skin.

Also, wear a pair of safety goggles for eye protection. Lastly, wear a respirator to avoid breathing in the fumes.

Clean The Work Area

As they stated earlier, epoxy adheres to most surfaces out there. Therefore, it’s important to cover your work area from any spillage during the project. You can use wax paper since epoxy doesn’t stick to it.

You also need to ensure that the surface you’re working on is free from dust and other pollutants.

This is because dirt affects epoxy’s feel, look, and effectiveness. So, start by cleaning the surface with dish soap and warm water.

Let the surface dry completely before you apply epoxy to it.

Ensure Adequate Ventilation

Epoxy products produce a low odour in their liquid state. This is an indication that they give off fumes. To protect yourself from these fumes, you need to consider room ventilation.

Luckily, there are various things you can do to ensure the room has enough ventilation. For instance, you can open windows, doors, and other openings.

This will increase air movement in the workspace. If you’re unable to open the windows, turn on the ceiling fan. This will help to remove the produced fumes away from the workspace.

You can also install other fans like desktop fans to keep the air flowing.

Gather Your Supplies

Remember, the resin has about 10 to 30 minutes of pot time. So time will get away from you quickly with such a short duration. Besides, this will make it very difficult to leave between the tasks to get some items.

That’s why you need to gather all the supplies you’ll need before you start your project. They also suggest that you create a resin supply checklist to help you with that.

FAQs About Epoxy

Do You Need Hardener For Epoxy Flooring?

These systems may require little or no hardener and often contain light-duty latex paints with added epoxy resin rather than true epoxy floor coatings. Do-it-yourself epoxy paints (different from true floor coatings) are often water or solvent-based.

They rely mainly, if not exclusively, on evaporation to harden and dry the final product. These systems may require little or no hardener and often contain light-duty latex paints with added epoxy resin rather than true epoxy floor coatings.

Can I Use Any Hardener With Epoxy?

On the other hand, epoxy resin can be used without hardener, but it will not cure or dry. Instead, it will remain in a liquid state until you add the hardener. For this reason, epoxy resins are often referred to as “two-part” systems because they require both resin and hardeners for curing.

As a rule, if the mixing ratio is the same, you can probably use someone else’s resin or hardener. It’s important to note the cure type and any peculiarities between the two, but they usually will be comparable.

Can I Use Epoxy Without Hardener?

Yes, it can. A lot will depend on the type of epoxy you are using and what method is recommended for curing without a hardener. The first thing to consider when curing epoxy resin without extra hardener would be how many catalysts were initially used in the mixture.

The Function of the Epoxy Hardener It is only when mixed with an epoxy hardener that they can cure properly. If applied onto a floor without the hardener, the resin would remain a near liquid indefinitely and could not transform into a durable flooring system.

What Is The Ratio Of Epoxy And Hardener?

Typically, this is 1: 1 or 2: 1 between resin and hardener, but there are also much more complicated ones, such as 100: 45. You can usually find the details on the packaging or containers.

The mixing ratio has to be very precise; otherwise, the epoxy resin will not harden, or it will not work optimally.

The equivalent weight can know the ratio of epoxy resin and hardener. For example, if the equivalent weight of the epoxy resin is 160 and the equivalent weight of the hardener is 40, the ratio of epoxy resin to hardener must be 160:40, which is 4:1.

What Happens When You Mix Resin And Hardener?

Mixing the resin and hardener prompts a chemical reaction between the two, transforming them from a liquid into a solid. Measuring accurately and mixing thoroughly is essential to making sure your epoxy resin cures properly.

Epoxy resin comes in two parts: a resin and a hardener. Mixing the resin and hardener together prompts a chemical reaction between the two, transforming them from a liquid into a solid. Measuring accurately and mixing thoroughly is essential to making sure your epoxy resin cures properly.

Are epoxy floors a good idea?

Extremely safe – Epoxy is a very safe coating for your hard floors. It’s slip resistant, shock resistant, and less abrasive than concrete and other types of industrial flooring. It’s also water resistant, and will protect your floor from any spills, including harsh chemicals that would harm other types of floor.

What are the disadvantages of epoxy flooring?

Cons of Epoxy Flooring

• Strong Application Fumes. During the epoxy application process, wet epoxy gives off an unpleasant smell. …
• Long Curing Time. …
• Slippery When Wet. …
• Economical Flooring Choice. …
• Resistant to Damage. …
• Weather-withstanding. …
• Aesthetically Pleasing. …
• Protects and Decreases Wear & Tear.

How long do epoxy floors last?

10 to 20 years   Long-Lasting, Environmentally-Friendly Floors Epoxy floors typically last 10 to 20 years and can last even longer with the proper maintenance and touch-ups. When it finally comes time to replace your floor, there will be no need for removal, and no need to throw away your old flooring.