Using 3D Printing to Make Strong Plastic Parts

Someone reached out to our M3D Pro community expressing interest in using a 3D printer for making spare parts for his veteran US car that are difficult to get. Replacements for the auto parts are likely to become one of the next frontiers for consumer 3D printing, especially for those looking to save (or even make) some money, as well as create parts that are otherwise not available on the market. We appreciate this application and just couldn’t pass on the opportunity to share some tips on how to use filament (3D Ink) based 3D printing as a tool for making extremely strong plastic parts for hardware, anchoring, fixing, enclosures, etc.

The Best Choice

Using resin SLA printers for mechanical parts like fittings would not be a good idea as they are gummy and break down in light. Your best choice for making strong plastic parts is undoubtedly a filament based 3D printer as no other affordable 3D printers can make structural 3D parts nearly as strong. We will be basing our suggestions on the M3D Pro 3D printer throughout this article as we found it to be quite suitable for the purpose in question.

It’s a Tool, Not a Hardware Store

You should see your M3D Pro as a tool, not so much a box of spare parts not yet printed. While a 3D printer will give you a base for your part, you should be prepared to do some post processing in order to achieve your desired finished product. For example, you can make nearly perfect nylon spacers but if you need nuts or press first, you should expect one simple post processing step like reaming or tapping to get maximum precision and roundness.

Optimal Resolution

For printing car parts and similar applications, we strongly recommend printing in the 350-500 micron resolution ranges, as well as getting a 0.5mm nozzle. This makes parts fuse together extremely well, so you can drill and not break the part in the z direction which is usually significantly weaker for smaller layers.

Please note that our recommended nozzle diameter applies to the M3D Pro printer only. The Pro has a standard nozzle of 0.4mm and the 0.5mm option is available for purchase as a replaceable add-on.

3D Ink

You will want to stay away from PLA that can warp even at 50°C temperatures and use higher cost filaments that are able to sustain higher temperatures instead.

  • For example, ABS-R shown above (which is similar to what is commonly known as PETG in many ways) would be good for replacement housings, mending parts, and spacers. It can handle 100°C temperatures and has a little more to give than PLA in terms of increased bonding, lower warp, and softer feel.
  • Tough 3D Ink handles 100°C just as well, and is a perfect replacement for rubber.
  • For the M3D Pro, we are also going to release POM (acetal) that can be used for very high-maintenance needs such as fuel resistance and low friction. On the down side, it can be a pain to print with just like nylon as it requires the maximum heated bed temps, smaller print sizes, and some patience.

All in all, correctly chosen 3D printer and printing materials together become one of the most powerful engineering tools (in line with a lathe, a CNC machine, or a reamer), but they still have their own capacity just like all other machines. We believe that it is very important to remember and respect the capacity of a 3D printer in the garage environment, as well as have fair expectations about its capabilities and its role among the rest of the tools in order to achieve the desired results successfully.

Posted in Helpful, M3D Answers on Jan 23, 2017

  • 3d-printer (1)
  • micropro (1)
  • cheap-3d-printer (0)