OOAK Table Tennis Forum

MAKING THE HARDNESS TEST IN PROPER WAY.
-- First of all, be sure you use an another rubber sheet as "bottom layer".
-- Avoid testing on the sandwich rubbers having a thin sponge < 1.8 millimeters.

It follows directly from my own testing works --you will always get inadequate results if only using one rubber sheet. Be sure to combine at least TWO rubber sheets for testing.
Through comparison of the test results, you can see an obvious difference. For example, when testing on a sheet of SANWEI Ghost 2mm the Shore-O durometer gives 51* degrees, while testing on the combination of 2 sheets gives 45* degrees. The latter is very well in accordance with the official factory specifications of 44 dgrs.

GENERAL ADVICE :
Take care to use 2 rubber sheets together for the hardness testing.