Epoxy resin is a solid material that can be utilized as a sealant and an adhesive, as well as many other things. One issue with epoxy resin is how thick and viscous it can be. This can create problems when using the epoxy such as air pockets in the finish, streaks, and self-leveling problems. The best way to settle this issue is to thin the epoxy. Let's review the different methods for thinning epoxy.
Note: It is important to understand the different methods of thinning epoxy and how they can be harmful to the strength characteristics of the product and the final cure.
Thinning with Solvents
By the most possible and the most used method for thinning epoxy. But, also the most harmful. Thinning the epoxy resin using a solvent is very damaging to the strength characteristics of the epoxy. Epoxy resin varies from brand to brand but, on average, there is a 35% decrease in its strength properties of the epoxy for ever 5% of thinner added to the mixture. Tread lightly when using a solvent with your epoxy. These methods can significantly affect the way you epoxy resin performs and also increase the total cure time of the epoxy.
Acetone or Paint Thinner
When using acetone or paint thinner for thinning epoxy, the general rule of thumb is a maximum of 10% added to the epoxy resin. An example would be if you had 32 ounces of epoxy that you were mixing you would only add up to 3.2 ounces of acetone to that mixture.
Recommend over acetone and other solvents. Denatured alcohol allows you to add more solvents to the batch without affecting as much of the physical properties of the epoxy. The general rule of thumb is a maximum of 20% added to the epoxy resin. An example would be if you had 32 ounces of epoxy that you were mixing you would only add up to 6.4 ounces of denatured alcohol to that mixture.
Thinning With Heat
Not as popular as thinning with solvent but still a very effective method of maintaining most of the strength characteristics in the epoxy. This process is accomplished by applying heat to the surface or the epoxy directly before applying the epoxy to your finished product. Heating the resin will drastically thin the epoxy down to a level that becomes more usable and main almost all of the physical traits of the epoxy.