Viscosity Testing

[rhodes2010]

I would like to hear from those that have done any viscosity testing.
Below is the definition of the SUS method, which I have seen quoted in technical articles.

I am looking at used viscosity equipment, but thought that some of you may have devised some simple DIY, at home use, methods for viscosity.

I would think that some of the important parameters would be:

1. temperature - being able to test at different temps. Equipment to take fluids to needed temps.
2. graduated containers - lab supply store pipettes or other cylinders.
3. A container with a hole that has a known flow rate at a given viscosity, or ability to determine the flow rate for testing.
4. Stop watch.

So, if I know the ambient temp, the temp of the fluid being tested, drop the measured quantity into the flow rate device, check the time = viscosity ?

SUS (SSU)—Saybolt Universal Seconds: The time, in seconds, for 60 ml of fluid to flow through a capillary tube in a Saybolt Universal viscosimeter at a given temperature. Usually measured at 100°F and 212°F. This term is being replaced by the centistoke, cSt.

I hope not to have endless links to heavily scientific journals with copius amounts of reading that tend to obfuscate the needed information.

Obfuscate: Def. To make so confused or opaque as to be difficult to perceive or understand.

Let's make this easy to read and understand.

[Lycoming-8]

I would be interested to know why you are interested in viscosity testing, as this would help to answer your questions. However just based on what you have provided so far, I would say your parameter list is pretty good.

The commercial viscometers that I have used to test viscosity of liquid fatty acids and esters, consisted of a temperature controlled bath, a viscometer tube, and a stop watch. The bath has to be controlled to quite a high tollerance if you expect to get absolute values, but probably not quite so well if you are only after comparative numbers. The bath has a high temp fluid, a mixer/stirrer, a thermostat, and a fixture for holding the special viscometer tubes. The tubes I have used had a built in reservoir, orifice, and exterior etched scratches defining the measurement start and stop points.

You fill the reservoir and set tube in the bath. After a specified time, you pressure or vacuum the fluid to the start point and then release and start the watch. Stop the watch when test fluid reaches the end point.

Calculation of the final number involves calibratiion constants for the tube and other values from a table for the bath temperature used. Unfortunately that is where you need to refer to the ASTM method write-up, or other technical info.