3D printing car parts IS the future ! 3D printing has made major advances over the last few years. While the principle of additive manufacturing is still the same (adding several layers of materials on top of each other) the selection of materials and the ways of adding layers have quite grown. About that we already have a blog entry here and a youtube video here.
3D Printing Car Parts With Resin
While modern consumer resin printers offer a layer resolution down to 0.02mm or even lower, the ratio of initial cost to build volume is still pretty big. In addition to that most resins do not offer the desired material capabilities we are looking for in car parts.
Resin printers on consumer level use small lcd screens to harden resin and allow a very high level of detail. This makes them very useful for small parts like, for example repro badges.
Hopefully we will have a more detailed look on SLA printing car parts in a future blog entry and video.
Talking about car parts, we most of the time talk about, metals like aluminum & steel, or synthetic materials like ABS & kevlar / carbon fiber composites. While there are a few ways for combining 3d printing and metal, we will first of all concentrate on the plastic side of view.
PLA, PETG, ABS & ASA
Those are all names, or to be more precise abbreviations of different materials used in FDM printing (Fused Deposition Modeling). FDM printing works by heating up the filament and extruding it via a nozzle onto a (often heated) print surface. The layer resolution with this method of 3D printing varies from usually 0.1mm to 0.4mm. While lacking the details of resin 3D printing, the usually far better rate of initial price to build volume and the variety of available materials makes more than up for it.
Different 3D Printing Material Examples:
- PLA – Polylactic Acid is by far the most common material / filament used today. It is very easy to use, has almost no shrinkage cooling down and needs the lowest print and heatbed temperatures. This makes it very good for rapid prototyping. For example for break caliper or steering rack adaptor. Since PLA has a very low glass transition temperature of around 60° celcius and is not oil, fuel or uv -resistant that’s about it for its usage in cars.
- PETG -Polyethylene terephthalate glycol-modified is a relatively new filament on consumer level. It combines the easy use of PLA with UV resistance and higher strength. That makes it a very good choice for interior parts like clips, gauge brackets or other kinds of non safety mounting brackets. Unfortunately it has a glass transition temperature of around 80°. Slightly higher than PLA, yet still low.
- ABS – Acrylnitril-Butadien-Styrol-Copolymer Yes that ABS of which the expensive bodykits were made back in the day. It has a glass transition temperature of 95°, is very resistant to all atmospheric conditions except UV rays and has a high strength and toughness. In addition to that it can be easily smoothed and “welded” with acetone. When well prepped and painted you can pretty much go from a 3D print design, to the printer, to the painter and onto the car. Unfortunately ABS needs higher temperatures, a well heated print bed and is prone to warping and shrinkage. It is by no means a big deal. But 3d printing beginners might struggle a while with it.
- ASA – Acrylester-Styrol-Acrylnitril Now we’re talking the good stuff! It combines the positive properties of ABS filament with a resistance against fats, oils, high temperatures and UV light. The glass transition temperature is above 110° celsius. The density of 1.07g/cm³ makes it very light for its strength.
Unfortunately with all its ups it has one downside of ABS, it is difficult to process. Warping, shrinkage, the whole shebang. But once mastered this is a very grateful material in versatile usage and / or post processing. It can be cut, milled, painted, glued, sanded and drilled without much of a hustle.
The Tools Of The Trade For 3D Printing Car Parts
Like with good tools in your workshop, a good 3D Printer makes 3D printing car parts a lot easier. And like with bad tools, a too cheap 3D Printer makes it much harder. Like working with cars, skill and experience can make do, but being a novice and having a low end 3D Printer can make it a slightly problematic endeavor.
Size Does Matter !
Having a huge build volume can make the difference between sanding, aligning, glueing, sanding again and after all of that noticing that your measurements were wrong – or just measuring and noticing your measurements were wrong. Don’t get me wrong. Do not spend ridiculous amounts of money to get the biggest 3D Printer ever, but be aware while selecting your first 3D Printer. 3D Printers are easy to upgrade (since they can print a lot of the upgrade parts themself) but build volume is harder to upgrade since most of the time you’ll need a completely new frame.