INITIAL SETTING TIME
Place the test block confined in the mould and resting on the non-porous plate, under the rod bearing the needle.
Lower the needle gently until it comes in contact with the surface of test block and quick release, allowing it to penetrate into the test block.
In the beginning the needle completely pierces the test block. Repeat this procedure i.e. quickly releasing the needle after every 2 minutes till the needle fails to pierce the block for about 5 mm measured from the bottom of the mould. Note this time (t2).
(C)FINAL SETTING TIME
For determining the final setting time, replace the needle of the Vicat’s apparatus by the needle with an annular attachment.
The cement is considered finally set when upon applying the final setting needle gently to the surface of the test block; the needle makes an impression thereon, while the attachment fails to do so. Record this time (t3).