3D Printing in Schools

How 3D printing works

Export the part/assembly from your 3D modelling software as an STL file Software that comes with the 3D printer slices the computer model into horizontal slices. The 3D printer the ‘builds’ the model slice by slice.

 

Stages showing the process of a 3D printed model car (support material is not shown for clarity). The printed model Time = circa 8 hours

Stages showing the process of a 3D printed model car (support material is not shown for clarity).
The printed model Time = circa 8 hours

Direct Digital Manufacture

One of the most significant growth areas in 3D printing is direct digital manufacture. 3D printing was developed as a faster way of prototyping parts for new designs. It has replaced many of the model makers who might take weeks to create an accurate mode of a design. 3D printing has developed to the point where production parts and even full assemblies are easily attainable. Recognising this, the terms additive manufacture (AM) and direct digital manufacture (DDM) are increasingly used to describe the process of 3D printing.

3D printing technologies

Extrusion deposition
Fused Deposition Modelling (FDM) extrudes material onto a platform. ABS, Clay, Eutectic metals, HDPE, Nylon, PLA, Plasticine, Porcelain, Precious Metal Clay, RTV, Rubber, Silicone.

Wire deposition
Electron Beam Freeform Fabrication (EBF3) can be used with most metal alloys.

Binding of granular materials
Processes include: Direct Metal Laser Sintering (DMLS), Electron Beam Melting (EBM), Selective Laser Melting (SLM), Selective Heat Sintering (SHS), Selective Laser Sintering (SLS).
Materials include: aluminium, ceramics, cobalt chrome alloys, corn starch, most metal alloys, magnesium, plaster of paris, thermoplastics, titanium alloys, stainless steel.

Lamination
Laminated Object Manufacture (LOM). Paper, card, MDF, metal foils, plastic film.

Photo polymerisation
Stereo Lithography was the first process to be widely adopted by industry and remains popular where accuracy and precision is important and can justify the high cost of the equipment. The process uses light curable resins and includes Stereolithography (STL) and Digital Light Processing (DLP).

Mask image projection
In this process, a jet deposits layers of liquid photopolymer and cures them with UV light. Multiple materials can be printed and parts with varying properties are possible by mixing polymers. With the budgets available to schools two technologies are gaining popularity in the classroom; Fuse Deposition Modelling (FDM) and the binding of granular materials.


Download complete article [download id=”9″]