There are lots of various rapid prototyping methods that you can adopt in terms of product phases and functional requirements. Here, we list six top prototyping ways, such as polyurethane vacuum casting, CNC machining, and three Plastic Three D printing methods: SLA, FDM and powder bed melting. And the pros and cons of each approach. In this way, you can make the most wisest decisions and choose the fast prototyping that works for you.
Six Fast Prototyping Ways
1. CNC machining: many people do not realize that NC machining is a desired molding method for the correct project. It is fast, accurate and versatile because it is suitable for almost any solid material, including plastics and metals. There is no minimum quantity, so one part can be made as easily as 1,000. You will want to use the way of CNC machining if you need powerful mechanical parts that are fully functional and have precise tolerances -- basically, complete production quality but in limited quantities. Numerical control processing is not ideal for thin-walled box or deep cavity. For these shapes, you can consider thermoforming, 3d printing or vacuum casting.
2. Polyurethane vacuum casting or vacuum casting, called “cast urethane”in US as well, uses solid master molds to make silicone rubber molds. Patterns can be made of any material, but usually plastic 3D printed parts. In the process, the master model is hanged in an empty casting box. The box is fulled of liquid silicone, which solidifies, cuts and removes the pattern, leaving a empty cavity that can now be refilled with cast resin to reproduce the original. If the master mold has a glossy or textured surface, this will faithfully replicate on the surface of each casting. So in many cases need to be secondary finishing. You can have a clear part as well, or any color you want. Vacuum casting is ideal for making plastic parts that look and behave like plastic injection molds and are close to producing quality without having to invest in expensive metal tools. Parts can also be reshaped, resin comes in various shore hardware, therefore you may make software and bendable parts-these things you can’t do with CNC machining for example. Silicone molds can make up to 20 copies, which is a great way to create shells and other small, semi-hollow forms that you can paint, sand and machine if you need to.
3. This was the first three-dimensional printing process for Stereo Lithography, and it has been improving. It went into commercial operation in 1980'. In order to use the SLA, you need to get a 3d cad model firstly and add support for it. Then separate the data into thousands of very thin layers. Employing a UV scanning laser, they pull each layer out one by one, curing the resin into a solid plastic 3D prototype. The Resin is fast and flexible, with a wide selection of resins that offer different cosmetic and mechanical properties. These are commonly separtated into various grades, such as standard, engineering or medical and dental. You can even add fiberglass or aluminum powder for greater strength. The Surface finish is very good, but remember that after printing, the part still needs to be cleaned and then cured again for maximum strength and stability. SLA components are hygroscopic too, meaning they absorb moisture over time. That’s the reason that we should keep them in a sealed bag, or in a drying cabinet.
4. The selections of laser melting SLM includes the use of high power lasers for the manufacture of metal parts, not only for sintering but also for the production of fully dense parts. The process actually happens in a sealed room with lots of inert gas, such as Argon. Nowadays, this method is becoming more and more fashionable not only in fast prototyping but also in small batch production. This is mainly because SLM is well suited for complex technical design, including hidden pockets, conformal cooling ducts, and other internal features. It allows you to lose weight while gaining strength, which is vital for aerospace, automotive and medical needs. Nevertherless, high-quality lasers can make this process expensive, and smaller scanning speeds many cause longer manufacturing cycles.
5. Fused deposition modeling is a 3D printing system that most people are familiar with. It uses ordinary plastic filaments such as polylactic acid or ABS, or engineered resins such as polyetherketone and vinyl ether. If you’re interested, you can read more about it here. The filament is extruded through a heated nozzle, melted, and then the melt layers pile up to form the part. It’s kind of like streamers. FDM is one of the cheapest three-dimensional printing methods and is the most popular for home enthusiasts and small carburetors. For prototyping developers, it’s usually easy to find a local manufacturer, spatial or digital printing bureau, that can help you print your design quickly and cheaply, but at a low resolution, so your parts may need more work done.
6. There are two main types of powder layer melting, Selective laser sintering melting (sls) and multi-nozzle melting (mjf) . They all use a sealed chamber filled with a powder substrate where the rollers are used to smooth and compress the top surface. Both systems are primarily nylon based. The Sls uses lasers to melt nylon, and mjf uses complex chemicals and infrared energy to melt nylon. Ultimately, both systems will provide you with a stable and moderately accurate functional test prototype. Mjf tends to reduce costs as quantities increase and is therefore somewhat more suitable than sls for small-batch production. There are several advantages to powder bed fusion. There are several advantages to powder bed fusion. First of all, the parts are self-supporting, so no additional construction is required. Second, the entire building volume of the combustion chamber can be used to achieve maximum efficiency. When using SLS, 75% of the original powder can be mixed with the original powder to save the cost of raw materials.