Viscosity Cup

A viscosity cup is essential equipment for successful spray finishing. Any finish's viscosity, its resistance to flow (we usually call it "thickness"), can change very significantly in response to changes in temperature, humidity, atmospheric pressure. This simple tool lets you measure how a finish is behaving on any given day, so you can thin or modify it as needed to assure predictable, consistent spraying performance.

We suggest you record your measurements to provide a benchmark as a way to help troubleshoot things when spray frustration strikes; trouble spraying the same product that sprayed flawlessly for you just a few weeks earlier. Of course do not forget the other variables like the effects of the weather on the atomization & drying of the finish, the size of the fluid tip, how far away from the surface you are holding your gun, the overall cleanliness of your spray gun and the shelf life of the product. (Just to name a few). When you open a new can of finish, stir it well and dip in the viscosity cup, lift straight up and let it drain, timing the seconds it takes to empty (or with more viscous finishes, for the stream to break). Record your time on the can of finish for reference, noting the date & temperature as well.

Cup is based on the #4 Ford cup style. (Color of cup may vary from photo)

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