Concept and design of Float-Ram, a new human powered press for compressed earth blocks

Compressed earth blocks constructions are appropriate for the improvement of the housing conditions in poor contexts, in particular in developing countries. The blocks are produced using manually operated presses, preferably bidirectional. The bidirectional human powered presses currently available are mechanically complex, difficult to use and very expensive. In order to overcome these issues, the paper presents the concept and the design of a new bidirectional human powered press for compressed earth blocks, called Float-Ram. The press is characterized by: the adoption of a floating mold, which provides a bi-directional pressing action in simple way; an optimized kinematic structure, based on a cam-roller follower transmission system; a general mechanical simplicity, since the node of all kinematic pairs is constituted by a single shaft. The Float-Ram, tested on the laboratory and on the field, can be considered as an important media for the diffusion of highquality raw earth building in developing countries.