So to the point. In our project (Robotics project) we mostly use sheet metal and PLA printed parts to build. But we want to level up and be ready for an advanced run and even low-volume production of the product. Right now we're in the last days of an advanced prototype (Phase II) . My question is, what do you guys recommend to level up the design and start to be ready for low-volume production (15 - 20 pieces)? What are the tips and tricks when designing a more finished product? For example, The two things we're considering to change are CNC machining the plastic parts that have high loads on them, and for other 3D printed parts we are considering using different technology than FDM printing. Right now plastic injection molding is not an option, we are not in mass production. Carbon composites are not an option too. I will be glad to hear from you about more ways of bringing the product closer to an industrial one and start thinking about low-volume production. Any article/guide will be great!
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1$\begingroup$ Have you tried outsourcing the components? A lot of times job shops will give you feedback to make the part easier to make for them, ie material selection, geometry, tolerances. Usually these changes are universally beneficial regardless who ends up making the parts. $\endgroup$– jkoApr 6, 2020 at 13:05
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1$\begingroup$ Can you define “low volume”? $\endgroup$– Eric SApr 6, 2020 at 13:19
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$\begingroup$ Injection moulding is not necceserily super expensive. For a run of 20 you can 3D print the mould with a sla printer... We do some injection moulding this way and our budgets are ridiculously low. Vacum casting, waterjet cutting and laser cutting also worth checking out $\endgroup$– joojaaApr 6, 2020 at 19:33
1 Answer
I believe your primary goal when transitioning from single prototypes to small batch production should be to improve manufacturability, and ensure that your design is scalable.
Examples of parts/systems that may need to be revised:
Parts that were made without drawings, for example by match drilling, or "freestyling"
Parts that are not easily obtainable in quantity
Parts/systems that have known issues, which were manageable for a single prototype.
Systems that require excessive manual labor for manufacture. For example hand soldered cable harnesses may need to be replaced with off-the-shelf options.
Parts that are functional, but not aesthetically pleasing may need to be replaced
I would recommend focusing less on methods, and more on results. Instead of asking "how do I level up", I would ask: "if I started making 20 of these right now, what problems would I run into".
To address the issue of 3D printed components. First ask yourself what the problem with them is, is it Aesthetics? Strength? Time? Cost? There is nothing inherently wrong with using 3D printed parts on a product.
There are other options, but they will all be more expensive than 3D printing (for 10-20 units) so you will probably want to have a good reason for choosing something else. Some alternatives:
- CNC, good looking and strong parts, but very expensive.
Laser cutting / water jet. Almost as cheap as 3d printing, strong materials, looks good. But the parts will need to be re-designed to be 2D
Resin molding. Not economical, in my experiance this is only used to simulate what an injection molded part will look like.
Other 3D printing. There are a lot of types, such as sintered plastic/metal, resin, etc that may be able to solve problems that your FDM PLA prints are having.
