RM (RAPID MANUFACTURING)

Rapid Manufacturing (RM) is an additive fabrication technique for manufacturing solid objects by the sequential delivery of energy and/or material to specified points in space to produce that part. Current practice is to control the manufacturing process by computer using a mathematical model created with the aid of a computer. Rapid manufacturing done in parallel batch production can provide a large advantage in speed and cost compared to alternative manufacturing techniques such as plastic injection molding or die casting. Rapid manufacturing may involve custom parts, replacement parts, short run production, or series production. (When the part is used in the development process only, the appropriate term is rapid prototyping.)

Rapid manufacturing for large products with layer-based manufacturing from metals, plastics, or composite materials is well known for several industrial applications in the military and aerospace sectors. Small products and microsystem applications are known in medical as well as consumer electronics, diagnostics and sensor technologies. Batch production of very small parts by rapid manufacturing techniques like RMPD offer cost and time advantages. Increasingly, rapid manufacturing is being applied to automotive, motor sports, jewelry, dentistry, orthodontics, medicine and collectibles.

Many differences for various RM processes	SRM (Silicone Rubber Molding)	CEM (Composite Epoxy Molding)	RT (Rapid Tooling)
1. Difference of quantity demand	Suitable for project below 100 pcs, and design with complex structure, such as undercut, which is hard to be demoulded from hard mould.	Suitable for project between 50-200 pcs, and design without complex structure, such as undercut, which is hard to be demoulded from hard mould.	Suitable for quantities between 200-5,000 pcs.
2. Difference of material choice	Use PU(Polyurethane resin) to simulate different performance of normal thermoplastic, such as ABS, PMMA, PP, PA, Rubber.	Use PU(Polyurethane resin) to simulate different performance of normal thermoplastics, such as ABS, PP.	Almost all possible plastic materials used in injection process, can be used on rapid tooling.
3. Difference of precision level	Because silicone mould is soft, when do casting, some factors would influence precision of final parts. Generally the tolerance could be about +/-0.15mm per 100mm.	Because composite epoxy mould is hard but normally big, when do casting, some factors would influence precision of final parts. Generally the tolerance could be about +/-0.15mm per 100mm.	Metal mould is hard, the final parts can reach much better precision, about +/-0.05mm per 100mm. The quality of final parts is smilar even same as those under conventional mass production.
4. Difference of material usage	Using PU(Polyurethane resin) to simulate different performance thermoplastic, just only approach limited kinds of plastic. And the final parts by SRM couldn't exactly reach the performance of real plastic material on mass production.	Using PU(Polyurethane resin) to simulate different performance thermoplastic, just only approach limited kinds of plastic. And the final parts by SRM couldn't exactly reach the performance of real plastic material on mass production.	Projects need special materials, such as high temperature resistance, flame resistance, anti-strike, food-grade material and medical-class material.