3D Printers

3D printing technology has been with us for quite some time (its roots date back to the 80s), but it has been truly popularized in the current decade, mainly thanks to the expiration of several patents strictly connected to the discussed technology and resulting in the decrease in 3D printer production costs.

At first, let us familiarize you with the process itself. We are going to briefly describe the SLA (stereolithography) process. It is based on additive element creation. The said procedure allows for gradually outlining horizontal cross-sections of a given element by means of laser. It scans a component soaked in a bath with a photopolymer (resin). Laser light stimulates the process of polymerization and solidification of a substance near the surface of a solution. After outlining a given layer, the platform is lowered by the exact thickness of the previous layer and the entire process is repeated until entire object is recreated by the printer.

The discussed technique ensures high precision and repeatability while at the same time maintaining remarkable surface quality and – in contrast to cheaper machining devices – allowing for recreating a complex internal structure of an element.

A CAD model has to be translated into a specific G-code, which can be properly handled by the machine. G-code generating software divides a model into layers and defines paths for the laser to follow. G-code may also generate fillings or supports in the model in order to strengthen the construction and allow for easier layer application.

Consecutive stages of SLA model creation are as follows:

  • Model creation in CAD
  • Exporting model to the *.stl format
  • Setting model design parameters: resolution, resin type, scraper type, minimum support height
  • Verifying the validity of *.stl files and geometry errors fixing
  • Designing the position and geometry of supporting elements
  • Verifying the geometry of supporting elements
  • Dividing the created 3D model into lays in accordance with the set parameters
  • Sending model-specific files to the device
  • Creating a physical model in the process of photopolymerization
  • Washing the model to remove remains of resin from it
  • Finishing the photopolymerization process in a PCA solidification device
  • Final processing of the model

 

Below, we present movie clips presenting the 3D printing process.

FormLab 2 printing process.

 

 

 

 

 

 

Photocentric printing process.

 

 

 

 

 

SLA spatial printing common use cases:

  • Prototyping – quick device or machine part prototype creation,
  • Device and machine parts production,
  • Product usability and shape tests, adjustment checks, durability analysis, attestations,
  • Verification of the validity of CAD models,
  • Specific tool creation,
  • Product presentation,
  • Recreating damaged elements or entire devices,
  • Creating parts, the manufacturing of which traditional methods are too costly or troublesome.

Advantages:

  • Ability to save time and limit the costs of prototyping,
  • High accuracy of models
  • High durability of printed products,
  • Ability to fully replicate the parameters of thermoplastic components (such as PLA, ABS, PET, and PMMA),
  • Mechanic processing of the prepared model (cutting, drilling, machining),
  • Ensuring model tightness,
  • Ability to print non-demountable moveable parts,
  • Possibility of applying various galvanic layers (chrome plating).

Disadvantages:

  • Layered layout of the model,
  • No possibility of replicating all the shapes,
  • In the case of filled elements, long printing time (several hours),
  • Limited mass production capabilities.

Below, there is a gallery presenting some of printed objects showing the possibilities granted by the utilization of the technology in question.