Prototyping made faster with 3D printing
There has been a lot of promotion about how 3D printing or additive manufacturing (AM) is going to change the industry, and I consider them to be totally correct. But, through what mechanism is it going to improve the industry? There are multiple answers to this question, but the one I consider that has a major impact is in accelerating the prototyping speed. The ability to begin a new design by 9:00 am, finish it by 4:00 pm, send it to the printer by 5:00 pm, and have a prototype by the following day is a game-changer. Also, if the same designer knows how to use the 3D printer, the same person can drive the whole workflow I just mentioned. Avoid having to send emails; explaining to the manufacturing engineer the desired material, color, how the part is going to be used, tolerances, asking for a quote, etc. All with the added benefit of reducing prototyping expenses.
Let’s compare this process with injection molding (IM), which is one of the most common manufacturing processes for plastics. Common lead times for IM are around 4-8 weeks for machining an aluminum mold. Lead time will vary depending on the complexity of the model. After that, getting the first injections may take about 2 to 3 days. However, the worst part about IM is having very little room for design changes after the mold has been machined, and the price of the mold is going to be humongous compared with a low volume production run of 3D printed parts. There is an escape route from these two caveats, which is producing a silicone mold for IM, but nowadays manufacturing providers are going to print your model anyway to generate the negative mold.
On the other hand, CNC machining is another traditional method and it’s much faster than IM. How much faster? It depends on the complexity of the model (thankfully complexity comes almost for free in 3D printing), how fast your provider generates the quote, and how agile their production process is. A rough estimate of their lead time could be around 2 weeks and the cost is going to be significantly smaller compared to IM. Sometimes CNC machining is compulsory if your model heavily depends on tight tolerances or high mechanical stress durability. If this is not the case, 3D printing is likely going to fit your needs and budget better.
Another traditional method that is even quicker and cheaper is sheet metal fabrication. Having lead times of about 1 week and cutting costs significantly is very close to 3D printing in those two aspects. The problem here relies on the limited complexity and overall shape of the model that can be manufactured with sheet metal. Good luck trying to replicate a heart valve model with sheets of metal.
Below you can review two charts that display how lead time and costs differ from each technology.
Creating prototypes quickly and cheaply is crucial in the very competitive development world we work in. Having the ability to validate your model in less than a week and having almost negligible manufacturing costs is going to set you ahead of competitors. As a designer myself, having the ability to print models to validate my teams’ models generates a huge amount of value and effectiveness.