How to make and test ceramic slip How to test your slip There are two properties of slip that we want to test frequently. They are specific gravity and viscosity.
Specific gravity means how much more than water does the slip weigh.
Lets say we weight out a gallon of slip and it weighs 14.4 lb. 1.73.This is a ratio, it is generally accepted that 1.75 is good for slip casting. So our slip is a little light at 14.4 lb. Okay, now we weigh the slip again and it is 14.5 pounds plus a little. Do the math and you can tell that you are right at 1.75.