The Gillmore Apparatus determines initial and final set times of Portland cement, masonry cement, hydraulic hydrated lime and certain mortars. Its adjustable support features horizontal arms to guide 2 stainless steel weighted needles with flat-end cylindrical tips.
It also features a base with an ample flat shelf for positioning specimens. A 1/4 pound and 1/12 inch diameter needle tests the molded specimen for the initial time of setting. A 1 pound and 1/24 inch diameter needle is used for the final set.