Post on 15-Jan-2017
DESIGNING FOR THE DMLS PROCESSJONATHAN BISSMEYER Senior Quality Engineer
ADDIT IVE MANUFACTURING | CNC MACHIN ING | IN JECTION MOLDING
ABOUT PROTO LABS
ADDIT IVE MANUFACTURING | CNC MACHIN ING | IN JECTION MOLDING
OUR EQUIPMENTConcept Laser M2 and Mlab machines
ADDIT IVE MANUFACTURING | CNC MACHIN ING | IN JECTION MOLDING
DESIGNING FOR DMLSNot a replacement for traditional machining, casting, sheet metal fabrication or metal injection molding (MIM)
ADDIT IVE MANUFACTURING | CNC MACHIN ING | IN JECTION MOLDING
Reduction of components Reduction of weight Quicker assembly times Reduction of cost Complexity
DESIGN GOALS FOR DMLS
ADDIT IVE MANUFACTURING | CNC MACHIN ING | IN JECTION MOLDING
Complex geometriesDESIGN GOALS FOR DMLS
ADDIT IVE MANUFACTURING | CNC MACHIN ING | IN JECTION MOLDING
Urban utility bike, EVOAllows riders to easily attach and
detach different components
CASE STUDY: HUGE DESIGN
ADDIT IVE MANUFACTURING | CNC MACHIN ING | IN JECTION MOLDING
DMLS was used to create the lugs, crankset shell and fork crown
CASE STUDY: HUGE DESIGN
DESIGN LIMITATIONS
ADDIT IVE MANUFACTURING | CNC MACHIN ING | IN JECTION MOLDING
SMALL FEATURE RESOLUTIONMinimum feature size:
0.150 mm (0.006 in.)
Mesh structures
ADDIT IVE MANUFACTURING | CNC MACHIN ING | IN JECTION MOLDING
THIN WALLS(<1 mm/0.040 in.)
Rule of thumb: 40 : 1
height : wall thickness
ADDIT IVE MANUFACTURING | CNC MACHIN ING | IN JECTION MOLDING
SURFACE ROUGHNESS
Material
Build parameters
Part orientation
ADDIT IVE MANUFACTURING | CNC MACHIN ING | IN JECTION MOLDING
SURFACE ROUGHNESSMachine Material Vertical
Sidewall (Ra)
Angled Upfacing Surface (45°) (Ra)
Upfacing Surface (Ra)
Angled Downfacing Surface (45°) (Ra)
Concept Laser M2 (250 mm)
Stainless Steel (316L) 195 225 395 565
Titanium (Ti64 ELI) 215 250 305 335
Aluminum (AlSi10Mg) 250 295 415 435
Inconel 718 350 405 610 960
Concept Laser Mlab (90 mm)
Stainless Steel (316L) 135 170 355 275
Stainless Steel (17-4 PH)
155 185 440 420
Cobalt Chrome 255 135 325 340
ADDIT IVE MANUFACTURING | CNC MACHIN ING | IN JECTION MOLDING
SUPPORTS
Connect the part to the platform
Hold features in place
Prevent warpingPhoto courtesy Concept Laser
ADDIT IVE MANUFACTURING | CNC MACHIN ING | IN JECTION MOLDING
SUPPORT removal processCan be intensive and may require machining, EDM
Design tip: Design parts that will require minimal supports. This will also improve part quality
Photo courtesy Concept Laser
DESIGN CONSIDERATIONS
ADDIT IVE MANUFACTURING | CNC MACHIN ING | IN JECTION MOLDING
INTERNAL FEATURES
Support and powder removal access
Design tip: Lattice structures can be used internally to reduce weight and provide support
Channels, overhangs, self-supporting angles, bridge dimensions
ADDIT IVE MANUFACTURING | CNC MACHIN ING | IN JECTION MOLDING
SELF-SUPPORTING ANGLES
CAD 50 degrees 45 degrees 40 degrees
35 degrees 30 degrees 25 degrees 20 degrees
ADDIT IVE MANUFACTURING | CNC MACHIN ING | IN JECTION MOLDING
OVERHANGSIf the next layer is larger than the previous layer,
it will create an overhang
DMLS has a small allowance for
unsupported overhangs (0.5 mm/0.020 in.)
ADDIT IVE MANUFACTURING | CNC MACHIN ING | IN JECTION MOLDING
CHANNELS AND HOLES
Channels and holes are self-supporting features
Great for conformal cooling applications
ADDIT IVE MANUFACTURING | CNC MACHIN ING | IN JECTION MOLDING
CHANNELS AND HOLESAs the diameter increases, the overhangs increase
8mm(.31”)
6mm(.24”)
5mm(.2”)
15mm(.6”)
12mm(.47”)
ADDIT IVE MANUFACTURING | CNC MACHIN ING | IN JECTION MOLDING
BRIDGES
1mm 2mm 3mm 4mm 5mm
Minimum allowable unsupported bridge distance is small (~2 mm/0.080 in.)
ADDIT IVE MANUFACTURING | CNC MACHIN ING | IN JECTION MOLDING
INTERNAL STRESSES | WARPAGEChanges in cross-sectional areas can lead to warpage
Large flat surfaces can bend build plates and shear bolts
Design tip: Design in additional material to gradually transition into larger cross-sections
ADDIT IVE MANUFACTURING | CNC MACHIN ING | IN JECTION MOLDING
DESIGN EXAMPLE: REV 1Three-component assembly Supports!
ADDIT IVE MANUFACTURING | CNC MACHIN ING | IN JECTION MOLDING
DESIGN EXAMPLE: REV 2Reduction of components/assembly time/weight …
BUT…
ADDIT IVE MANUFACTURING | CNC MACHIN ING | IN JECTION MOLDING
DESIGN EXAMPLE: REV 3Best surface finish, small warpage potential
Self-supporting features eliminate need for most supports
ADDIT IVE MANUFACTURING | CNC MACHIN ING | IN JECTION MOLDING
PROTOTYPING OR PRODUCTION
DMLS can be a production method for
complex geometries
DMLS is also a low-cost, quick-turn
method for prototyping
components using actual end-use
materials
OPTIMIZE DESIGN HIGHER VOLUME
ADDIT IVE MANUFACTURING | CNC MACHIN ING | IN JECTION MOLDING
CASE STUDYTRANSITION TO CONVENTIONAL MFG
Total Cost (Tooling + Parts)DMLS
MIM
Part Quantity
Cost
0 100 200 300 400
Breakeven point
CONCLUSIONDMLS opens up new design options,
but it will not replace conventional manufacturing methods
Understanding constraints will maximize benefits of DMLS for part
design
QUESTIONS?