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document updated a month ago, on May 10, 2024

epoxy viscosity

how to increase viscosity

epoxy fillers

Epoxy fillers are incredibly handy, as they let you dial in the desired level of thickness — ketchup consistency, mayonnaise consistency, and peanut butter consistency.

wait some time

Epoxy gradually firms up as it cures, and there's a period where it's becoming somewhat stiff but can still be shaped some. Each epoxy product has a different quoted work time. If the epoxy is significantly colder or warmer than normal, that will definitely adjust the work time as well.

Some epoxies, such as Apoxie Sculpt, specifically advertise this feature. (On that page, they refer to "cure stages", such as waiting 10 minutes, or waiting 20 minutes. Total work time is quoted as 1-3 hours.)

cooling

If you cool the two components before mixing them, it will definitely thicken the epoxy [2]. However, air bubbles will stay trapped in the resin more easily.

how to decrease viscosity

additives

Adding lacquer thinner or denatured alcohol to epoxy will thin it out. [1] [2]

heating

Heating the two components before combining them also decreases the viscosity. However, I heard there's a limit, after which overheating decreases the working time significantly. (TODO — expand)