Electroforming enables metallic parts manufacturing with good mechanical properties and high level of accuracy and reproducibility. A thin metallic shell is deposited on a model and later released from it. There are several applications of electroforming combined with rapid prototyping: injection moulds, EDM electrodes, moulds for rotational moulding, complex metallic parts, etc. However the two main disadvantages of electroforming are the non uniform thicknesses distribution and high time of shell manufacturing. The paper focuses on a new development in order to achieve uniform thickness and otherwise a faster shell manufacturing. A new device and software have been developed, named Elecform3D™. The device is an automatic machine controlled by computer and assembled into the electroforming equipment. Otherwise the software not only controls the device but also simulates and calculates the optimal positions of the cathode based in the electrolytic parameters of the bath. The software recommends an automatic program of movements or allows the operator to decide another alternatives programs if necessary. Elecform 3D is an important step beyond electroforming so far. RP 3D printer combined with Elecform 3D is a cheaper alternative for high quality metallic parts manufacturing in comparison with SLS-SLM technologies or high speed machining, mainly for rapid tooling and even rapid manufacturing.

Rotomoulded plastic parts have no internal stresses, as it is a process carried out at lower temperatures than injection moulding and no pressure is applied. The main disadvantage is the high cycle times needed. This paper focuses on reducing this cycle time and in producing a mould using standardized parts. For cycle time reducing, it is proposed to heat the mould by thermal fluid in continuous circulation; heat transfer processes have been studied for over 20 different configurations of the oil’s inlet – outlet, obtaining acceptable results with a manifold with 25 perforations in the front and rear faces. This configuration has been optimized by computational fluids dynamics, allowing reducing heating and cooling time and improving the energetic efficiency and the uniformity of heating. Design, simulations and testing of a 100 mm3 cube have been carried out in order to produce a standardized mould; this mould consists in some standardized parts and a nickel shell, obtained by rapid prototyping and electroforming process. This shell can be removed from the rest of elements in the mould, allowing thus to obtain parts with any other geometry just by changing the nickel shell. An experimental machine for testing has been developed as well.

Rotational moulding is a method to produce hollow plastic articles. Heating is normally carried out by placing the mould into a hot air oven where the plastic material in the mould is heated. The most common cooling media are water and forced air. Due to the inefficient nature of conventional hot air ovens most of the energy supplied by the oven does not go to heat the plastic and as a consequence the procedure has very long cycle times. Direct oil heating is an effective alternative in order to achieve better energy efficiency and cycle times. This research work has combined this technology with new innovative design of mould, applying the advantages of electroforming and rapid prototyping. Complex cavity geometries are manufactured by electroforming from a rapid prototyping mandrel. The approach involves conformal heating and cooling channels, where the oil flows into a parallel channel to the electroformed cavity (nickel or copper). Because of this the mould enables high temperature uniformity with direct heating and cooling of the electroformed shell. Uniform heating and cooling is important not only for good quality parts but also for good uniform wall thickness distribution in the rotationally moulded part. The experimental work with the manufactured prototype mould has enabled analysis of the thermal uniformity in the cavity, under different temperatures.

Nowadays, the natural fibres market is having an important growth due to the commitment of contemporary society with the sustainable development that leads the natural resources preservation and the environment protection. Fibres from banana food wastes provide high mechanical properties related to other natural fibers such as flax, sisal, hemp, etc. The aim of the present research work is to compare different banana fibres processing in order to improve the matrix fibre adhesion and behavior of fibre under processing conditions. Simple Anova analysis has been implemented on four different formulations: 1. No fibre processing, 2. Alkaline processing with Caustic Soda (NaOH), 3 Maleic Anhydride, 4. Combination of Soda and Maleic Anhydride. Several samples of MTT 8040 resin, under vacuum casting, with silicone moulds, conditions, have been done. Mechanical properties and efficiency factors of adhesion fibre-matrix have been determined and compared.