How to use a hydrometer
A hydrometer is a tool used to measure the specific gravity of a glaze, which will tell you how thick the glaze is.
– Thoroughly stir the glaze
– Put exactly 1,000 milliliters of the glaze into the beaker labeled “Hydrometer Testing”
– Wet the hydrometer
– Carefully lower the wet hydrometer into the beaker with the glaze in it
– Wait at least 15 seconds for the hydrometer to naturally settle into the glaze
– Gently tap the side of the beaker a few times to make sure hydrometer completely settles
REMEMBER: Glazes will have different hydrometer readings. Here is the list of approximate measurements that our glazes should read on our hydrometer:
|Liz Kraus Shino||50|
|Steve’s Copper Red||52|
|Jeff’s Long Beach Blue||53|
|Steven Hill Clear||49|
|Cushing Satin Black||52.5|
|Horsley’s Satin Matte White||50|
– When testing, if the number on the hydrometer is higher than listed above, add a little water and repeat the testing process until the hydrometer reads the correct number.
– If the number is lower than listed above, make a note on the bucket to have someone screen some water off the top of the liquid amount. (This of course has to be done AFTER the glaze has settled – usually after a day or so has gone by without anyone stirring the glaze) After screening some water off, then repeat the testing process until the hydrometer reads the proper number.
Here’s a Ceramics Arts Daily article on how to make your own hydrometer: http://ceramicartsdaily.org/clay-tools/making-clay-tools/how-to-make-a-floating-stick-hydrometer-for-the-cost-of-a-milkshake/