How to check the balance of your D20 with the dice float test - Original
A 2015 video on YouTube with instructions for the salt water test.
The salt water test or dice float test is a way to test the mass distribution (weighting) of certain dice (i.e. those that can float like those made of plastic, but not metal), in particular to test whether the weighting favours specific results more than others. In brief, a large amount of salt is dissolved in warmer-than-room-temperature water and then a die is placed in it to float. If the die consistently rolls in the water to show the same face on its upside when disturbed, then it is unfairly weighted and biased.
It is a simple test of dice bias, although not hugely precise, and in practice when rolled on a table dice bias is more likely to be caused by imperfections in the die's shape rather than its internal mass distribution. Rolling a die many times and counting how often each of its results happens remains the most reliable way to check for dice bias.
External links[]
- Discussion "Is the Saltwater Float represented in this question a good way to test for loaded dice?" at RPG StackExchange, including commentary and tips about how to perform the test properly