Molding machines and methods of performing molding processes are described. One embodiment includes a base, a carriage disposed movably on the base, a first mold secured immovably to the carriage, a second mold disposed slidably on the carriage, a driving unit for moving the second mold on the carriage and toward and away from the first mold, a push shaft inserted telescopically into a pressure cylinder and pushing the second mold against the first mold, a synchronous transmission unit for moving said carriage synchronously with the second mold so that the first mold is moved to said second mold, and a pressure booster including a booster tube, and a telescopic booster rod extendable into the booster tube to transfer pressure in the booster tube to the pressure cylinder so as to boost the pressure inside the pressure cylinder.