Abstract: A hand operated ratchet tool includes first and second pivotally coupled jaws, first and second links pivotally coupled to the first and second jaws, respectively, a third link pivotally coupled in common with the first and second links, and first and second handles pivotally coupled with the first and third links, respectively, and with one another. First and second pawls are mounted on the pivots between the third link and second handle and between the first link and first handle, respectively. Each alternately engage with teeth provided along a semi-circular edge of the second link to rotate the second link in a direction which closes the adjoining working faces of the jaws. The first pawl has two separate sets of teeth configured to respectively engage with the link teeth when the second link is being rotated in either of two opposing directions to open and close the jaws.

Abstract: A mold or parts of the mold are removed from a casting following solidification and cooling by immersing the casting with mold or mold particles still attached in a liquid such as oil or water and focusing shock waves onto interface portions to obtain ablation and spalling of the mold material to be removed from the casting.