Abstract
Generally moisture control of the raw sand without coating, as raw machine molding sand, needs skill at the time of sand-mixing, moreover if it is not controled in proper moisture, it can not be called the good sand. Ther upon I investigated about ideal moistures of sands, especially in connection with its fineness number, in accordance with the relation of moisture sand and its physical test values. The results of this experiments are as follows : 1) The moisture is nearly same when permeabiliry and transverse strength of sand showes the maximum. 2) The ideal moisture of sand is increased gradually, according as its fineness number becomes greater.
