Not every single item that goes into production needs to be manufactured by the bulk. Some pieces and bits require just a small production run that goes accordingly to the budget of the planning stages and the prototype of a project. To determine the real production run of a single part, a study has to be made, and there will also be a need to crunch a few numbers to get a pretty clear picture of what is needed. Factors like size, design, complexity, and materials will determine the final costs of the run as well as the delivery time for it.
With that in mind we can check the most commonly used methods to handle low productions runs of plastics in modern manufacturing:
3D Printing
This is the most popular method of crafting prototypes these days by almost every manufacturer out there. The technique itself has brought down the costs of creating prototypes to an all-time low with the use of materials such as polymers and plastics to bring forward the parts needed to construct fully functional designs.
3D printing is especially useful when classic tooling becomes cost-prohibitive for something that is really small; it also allows handling future alterations on designs since the product is essentially created using computer software, so upgrading turns into a cheap process too.
The ideal batch size for this method is 200 pieces max, and they can be delivered between 3 to 5 days using Selective Laser Sintering while using other options of material such as nylon and fibers.
Silicon Molding
Also called vacuum casting, this the way to create plastic parts using silicon molds. The process is handled very much like 3D printing, using customary software specially designed to handle creation and modifications at early stages of production. The main difference with 3D printing resides in the use of a technique called stereo lithography that uses master patterns exclusively to create these molds under vacuum environments.
The word that best defines this technique is “precision” since silicone allows for a wide range of details and textures that replicate the original design and translate better in the creation of final molds. The ideal batch size for this method shouldn’t go up above 50 pieces with a turn-around time of 3 to 5 days while using other options of material such as Polypropylene, ABS and certain variations of PVC.
Injection Molding
While it’s classified as a different method of crafting, this is actually another branch of 3D printing by using more modern and detailed molds that allow further evaluation of the parts being produced. Polyjet materials are the optimal choice to cast these parts since they usually translate better into a good rendition of what the finished product will be once the testing phase it’s done.
When approval is passed, the same molds can be used with the actual manufacturing materials with higher production values and to ensure smooth finishes that needs little to no trimming when they are done. The ideal production runs of this method should not be more than 50 pieces with a planned delivery timed to 5 days tops and only using specialty molding thermoplastics.