SFF Layered Manufacturing Technologies Powder Solidification 3D Printing (3DP) Selective Laser Sintering (SLS) Additive With Sacrificial Supports Stereolithography (SLA) {= Liquid solidification} Thermoplastic deposition Fused Deposition Modeling (FDM) Solid Object Printing w/ Multi-Jet Modeling (MJM) Solidscape’s ModelMaker {previously: Sanders} “Subtractive” Laminated Object Manufacturing (LOM) SFF Layered Solidification Processes Liquid-Based Approaches Stereolithography (latest process needs almost no “supports”) Powder-Bed Based Approaches 3D Printing (Z-Corporation) Selective Laser Sintering SFF Stereolithography (SLA) First commercial layered manufacturing technology (1988) Photo-curable liquid resin www.3dsystems.com SFF Stereolithography (SLA) UV laser beam solidifies the top layer of a photosensitive liquid. UV Laser Beam Photopolymer Build Stage SFF Stereolithography: Apparatus SFF Stereolithography Pre-process: Orient part. Choose Slice slice thickness. parts and plan supports. SFF Stereolithography Process: Position build platform (stage) just below liquid resin surface. Smooth surface with re-coater blade. Scan the outline of the current slice, loosely hatch part interior with laser. Lower the build platform for next layer. SFF Stereolithography Post-process: Raise part and drain out liquid. (except liquid trapped by loose hatch) Break off supports. Rinse in isopropanol and water. Dry with air hose. Post-cure (strengthen) in UV oven. SFF Stereolithography Characteristics: Slow process Supports must be removed by hand Lab environment necessary (gasses!) Needs trained operator Laser lasts 2000hrs, costs $20’000! Little material choice, ($700 per gallon) Parts can be brittle, fragile SFF Stereolithography Characteristics (cont.): High accuracy Layer thickness 0.001 - 0.006” Minimum feature size 0.003 - 0.012” Large build volume Up to 20 x 20 x 23” SFF Powder-based Approaches Key Properties: Needs no supports that must be removed! Uniform This bed of powder acts as support. powder gets selectively (locally) glued (or fused) together to create the solid portions of the desired part. SFF 3D Printing -- Principle Selectively deposit binder droplets onto a bed of powder to form locally solid parts. Head Powder Spreading Printing Powder Feeder Build SFF 3D Printing: Some Key Players Z Corporation: http://www.zcorp.com/ Plaster and starch powders for visualization models. Soligen: http://www.zcorp.com/ Metal and ceramic powders for operational prototypes. ProMetal: http://www.prometal-rt.com/ Metal sintering process for operational prototypes and art work. Therics Inc.: http://www.therics.com/ Biopharmaceutical products, tissue engineering. SFF 3D Printing: Z Corporation The Z402 3D Printer Speed: 1-2 vertical inches per hour Build Volume: 8" x 10" x 8" Thickness: 3 to 10 mils, selectable SFF 3D Printing: Z Corporation SFF 3D Printing: Z Corporation Digging out SFF Optional Curing: 30 min. @ 200ºF Keep some powder in place <-- Tray for transport SFF 3D Printing: Z Corporation Cleaning up in the de-powdering station SFF 3D Printing: Z Corporation The finished part Zcorp, 6" 6 diam., hrs. SFF 120 Cell -- Close-up SFF Parallel Projection of the 4D 120-Cell Zcorp, 6" 6 diam., hrs. SFF Morin Surface 3D-Print 6" diam. 5 hrs. This is the half-way point of a sphere eversion (without causing creases or tears). SFF 3D Color Printing: Z Corporation The Z402C 3D Color Printer Differences compared to mono-color printer: Color print head with: Cyan, Yellow, Magenta, Black, and Neutral. Smaller build area. Specs: Speed: 0.33 - 0.66 vertical inches per hour Build Volume: 6" x 6" x 6" Layer Thickness: 3 to 10 mils, selectable Color depth: 80 mils below surface SFF 3D Color Printing: Z Corporation SFF 3D Color Printing: Z Corporation Use compressed air to blow out central hollow space. SFF 3D Color Printing: Z Corporation Infiltrate Alkyl Cyanoacrylane Ester = “super-glue” to harden parts and to intensify colors. SFF 3D Color Printing: Z Corporation “Lizard-Frame”: Final Infiltrated Part SFF Hypercube, Perspective Projections SFF Two Ways to Make a Hypercube 3D Color Print Assembly of flat FDM parts ==> SFF What Can Go Wrong ? -- Parts may brake before infiltration SFF What Else Can Go Wrong ? Blocked glue lines Crumbling parts SFF What Else Can Go Wrong ? Some blocked glue lines Uneven coloring Art ? SFF Post-Processing for 3D-Printing Surface is porous, dusty. Seal and strengthen the part: Dip in wax: Nice smooth finish Needs separate waxing station Infiltrate with “superglue”: Tedious, dirty manual labor Spray-paint with a sealant: Polyurethane (yellowish, smelly) Krylon (invisible) SFF Post-Processing for 3D-Printing Spray-paint surface with Krylon SFF 3D Printing: Z Corporation An Informal Evaluation Fast ! Running expenses: moderate, (but overpriced powder) Color print head and tubes need some care in maintenance. Somewhat Lot’s messy cleanup ! of dust everywhere ... SFF Selective Laser Sintering (SLS) Key Points: Powder gets solidified with a laser. Powder is kept just below melting point, heat from laser will fuse powder grains. Un-fused powder acts as support, can easily be removed later. Many different materials can be used when mixed with a suitable binder: nylon, metal, ceramics … SFF SLS: Conceptual View SFF SLS Players 3D SYSTEMS Representing the fourth generation of SLS® (selective laser sintering) technology, Vanguard™ and Vanguard™ HS (High Speed), are the first SLS® systems developed specifically for advanced manufacturing applications. With the Vanguard system you can move directly from a CAD file to a durable, functional plastic or metal part or tool — in a fraction of the time required for traditional machining and tooling. http://www.3dsystems.com/products/sls/vanguard/index.asp SFF SLS from 3D SYSTEMS Use • • • • • Vanguard or Vanguard HS system for: Plastic or metal parts, patterns & prototypes Complex metal tooling inserts Highly Durable Parts Parts with small features Short runs of plastic & metal parts Benefits: • High part accuracy • Fast build speed • Unattended operation • Uses plastic or metal materials • Respond to customer demands • Worldwide service and support SFF SLS: Laserform Parts SFF The Most Challenging SFF Part 3rd-order 3D Hilbert Curve: much weight much length no supports only two tubeconnections between the two halves. SFF Fabricated by ProMetal SFF ProMetal Process A ‘green’ part is first formed, composed of stainless steel powder and a selectively applied binder. This part is built bottom-up, layer-by-layer under direct computer control. This green part is then sintered, the binder is drained out and replaced by liquid bronze. ProMetal is a division of ‘The Ex One Company’, Irwin, PA. SFF The Objet PolyJet Process SFF The Objet PolyJet Process Pointer to the company: http://www.2objet.com/ See the movie ... http://www.youtube.com/watch?v=oMQWGBgNCtg SFF Which Process Should You Pick? Do you need a prototype (not just a model)? SLS, FDM (for robustness, strength). Do you need a mold for a small batch? SLA (for smooth, hard surface). Does part need multiple colors? 3D Color-Printing. Does part have convoluted internal spaces? 3D-Print, SLS, SLA (easy support removal). SFF Informal Process Ratings Matrix Hollow Hollow 2 Nested, Sphere Sphere with Perforated Drain/Vent Spheres 3D Hilbert Pipe Preassembled Gear Mechanism LOM (F) F F D F SLA FDM 3D-P SLS (F) (F) (F) (F) A F A A B C A A B C C B C D B B