how can epoxy viscosity be reduced?

What’s the best way to reduce the viscosity of epoxy? Acetone, right? Nope. What about rubbing alcohol? You’re off again.

Cornstarch? Not a chance! There’s one thing that will thicken epoxy resin and it’s a little-known secret among working artists: glue sticks.

You may have seen these in your local art supply store—they’re often used by kids at school who want to make collages with paper cutouts and photos.

But there are several kinds that can be used as additives in paint or even as primary ingredients in some mediums like acrylic painting (which is basically just paint mixed with water).

So if you’re looking for an easy way to thicken up your epoxy resin or other paints without adding extra chemicals, give these sticky rectangles a try!

How do you thin out epoxy?

The most common way to thin out epoxy is by using a solvent. Solvents are substances that dissolve the epoxy and make it easier to apply. However, there are a few things you should keep in mind:

  • Make sure the solvent dissolves the epoxy. If it doesn’t dissolve the epoxy, it won’t help you!
  • Make sure the solvent is compatible with your application, whether that be a boat finish or a floor finish. If it isn’t compatible with your application or environment, then again: no good can come of this!

How do you make epoxy less runny?

First, you can use a thicker epoxy. The choice of the right viscosity is always important when you are using an epoxy product.

If the viscosity is too low, mixing may be difficult and application is not even. On the other hand, if it has too high viscosity you will have problems with spreading and filling in details like screw holes or seams.

Second, use slower curing epoxies so that your work time remains longer than what is required for proper filling of imperfections and voids in wood joints like knots, etc.

This way you can fill them properly before they cure out completely which would result in getting cracks on your woodwork projects at later stages (after several days).

Thirdly, select slow-hardening epoxy glues so that they don’t dry out before you have had sufficient time to fill up those imperfections using any kind of filler material such as sawdust or wood flour, etc.

How much acetone does it take to thin epoxy?

Acetone is a great solvent for epoxy. Acetone is also the most common solvent used to thin epoxy resin and glue. You can add acetone to your epoxy resin or glue in different amounts depending on how you want the final product to look and feel.

If you’re using clear epoxy resin, adding too much acetone will make it appear milky or cloudy. This means that there is more than enough solvent in your mix and more mixing won’t help this situation (you’ll just end up with an unattractive finish). If you’ve added too much acetone, just add some more catalyst until you get the desired viscosity back again.

Alternatively, if your project requires a higher viscosity product like an adhesive that’s not as runny as regular old paint but still thin enough for brushing onto surfaces without running off before application begins then adding too much catalyst will cause problems with adhesion.”

Can I thin epoxy with isopropyl alcohol?

It can be done, but you might not want to.

First of all, isopropyl alcohol (sometimes called isopropanol or 2-propanol) has a high evaporation rate and low viscosity.

This means it will evaporate quickly, which is great for thinning out epoxies that have thickened over time or have been stored in hot conditions. But because of this property and the fact that it’s flammable, isopropyl alcohol also has some negative side effects:

  • Vapors may cause eye irritation if inhaled or come into contact with your eyes; skin irritation if exposed to vapors or comes into contact with your skin; drowsiness; confusion; nausea; vomiting; dizziness; tremors; seizures (in severe cases); coma (in extreme cases). If ingested by humans or animals/pets/companion animals/etc., can cause gastrointestinal disorders including nausea, vomiting, and diarrhea.
  • Inhalation at high concentrations can cause respiratory tract irritation and damage.

What is low viscosity epoxy?

Low viscosity epoxy is used for thin films, bonding, sealing, adhering, and coating.

Low viscosity epoxy is a more liquid version of the high-molecular-weight epoxy resin. This resin has a very low specific gravity that allows it to flow easily when in use.

How do you make epoxy thicker?

To make the epoxy thicker, add more hardener and/or resin. This can be done by measuring out a certain amount of each component and mixing them together.

However, it’s easier to use a thickener for this purpose instead. Thickening agents are sold alongside epoxies in hardware stores or online retailers like Amazon and Etsy.

They’re usually powders that you add before pouring your mixture into the container for curing. Some thickening agents work better than others; some even reduce viscosity without changing the ratio of epoxy to hardener needed in order for it to cure properly!

How do you stiffen epoxy resin?

You can stiffen epoxy resin by adding a hardener, thickener, or filler. A catalyst, resin activator, or retarder may also be used to change the rate of cure.

Thickening agents are usually polymers that are added to the base resin in order to thicken it and decrease its working time (the amount of time you have before your project sets).

Some common thickening agents include polyester resins like West System’s 105 Resin Accelerator, polyamide-imide resins like West System’s 209 Marine Boating Enamel Thickener, and polyethylene terephthalate (PET) plasticizers such as Dow Chemical’s 628 Polyester/Polyamide Plasticizer Acetylated Bisphenol-A.

A filler is an inert material added to the base resin in order to increase its volume without adding much strength or stiffness.

Natural fillers include glass fibers; synthetic fillers include carbon fiber and Kevlar® brand yarns manufactured by DuPont Corporation.

Can I use cornstarch to thicken epoxy?

Yes, you can use cornstarch to thicken epoxy. You should add it according to the instructions for your particular epoxy. Most companies will tell you how much cornstarch (or another thickener) to use per gallon of epoxy.

The most common way to thicken epoxy is with a polyvinyl alcohol (PVA) or polyvinyl acetate (PVAc) solution that’s mixed into one-part resin and two-part hardener by volume.

This solution will work well with both polyurethane and polyester resins and achieve the correct consistency for most projects.


We have looked at some of the ways that you can reduce the viscosity of epoxy. There are lots of possible solutions, and they all have their pros and cons.

It is important to think about what type of finish you want before deciding which method will work best for you.

Leave a Comment