Concrete block mould Our moulds are made of high quality steel and available in various shapes and sizes. The mould is best placed on a steel or plastic base, release agent applied. Concrete poured in, indeally vibrated using a poker then left to cure for 24 hours. Once cured the catch pin is removed and the L shapes moved away and the remaining block turned over using a fork lift or equivalent, then moved using a scissor lift ideally). The finished blocks are often used for retaining walls, aggregate bays, silage pits, road blocks and temporary and moveable walling solution.