Rapid Tooling

Rapid ToolingRapid Tooling

Most applications inMost applications in

Mold for injection molding

Mold for die casting

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Core and CavityCore and Cavity


Insert & molded componentInsert & molded component


Typical die cast partsTypical die cast parts


Global MarketGlobal Market

• Injection molded parts: $ 20 billion• Die cast components: $ 10 billionDie cast components: $ 10 billion


Conventional approach for fabricationConventional approach for fabricationCNC milling, grinding, EDM, etc. have design restrictions, accuracy problem and more fabrication timeaccuracy problem, and more fabrication time.


Modular ToolingModular Tooling


Injection Moulding InsertsInjection Moulding Inserts

• Ejector pins• Conformal colling channelsConformal colling channels


Cavity insertsCavity inserts


Rapid Tooling DefinitionRapid Tooling Definition

• Techniques employed to develop required tooling quickly enough so as to reduce g q y glead-time drastically.

• More stricter definition: Tooling• More stricter definition: - Tooling developed using rapid prototyping technology, directly or indirectly, at some point.p


ClassificationClassificationI di t T liIndirect ToolingTooling generated using a master pattern g g g p

(often a rapid prototype model, but also hand made or machined pattern).p )1. Cast Resin2 Cast Metal2. Cast Metal3. Metal Spray4 Nickel Shell & Galvanoforming4. Nickel Shell & Galvanoforming5. Sintered Metal Tooling


ClassificationClassification

Direct ToolingTooling directly manufactured on rapidTooling directly manufactured on rapid

prototyping machine.6 Di t AIM St lith h T li6. Direct AIM Stereolithography Tooling7. Laser Sintered Metal Tooling8. Laser Powder Melting Tooling9. Laminated Tooling9. Laminated Tooling


1 Cast Resin Tooling1. Cast Resin ToolingM t l d (t i ll Al i i ) fill d E• Metal powder (typically Aluminium) filled Epoxy Resin C t d ti l id t t• Cast around a conventional or rapid prototype master to form the tool cavity M t i d ft i iti l i • Master is removed after initial curing

• Cast Tool is post cured at elevated temperature • Specially formulated for injection molding• Placed inside a steel bolster during injection

molding to sustain the clamping/injection forces.


Cast resin tool of an automotive part


Di d tAd t Disadvantages– Limited production

l

Advantages– Very quick to

d volume– Prone to surface

d d ti

produce– Relatively cheap

degradation– Due to poor

d ti it f th

– Can be repaired quickly

conductivity of the resin moulding cycle time iscycle time is significantly (2-3 times) longertimes) longer.


•While aluminum molds will cool the part much faster, ppolymer molds show a bad thermal conductivity. •This leads to long cycle times and differing part properties, especially with semicrystalline materials like polypropyleneespecially with semicrystalline materials like polypropylene or nylon. •Longer cooling times lead to increased strength, butLonger cooling times lead to increased strength, but reduce toughness.


• Typically 50 parts in polypropylene and 50 parts in nylon could be manufactured with this cast resin mold

• Both the cast resin molds were 100% aluminum filled But the• Both the cast resin molds were 100% aluminum filled. But the second one was made of a different resin of low mechanical strength.

• While the parts from the first mold showed a very smooth surface• While the parts from the first mold showed a very smooth surface, the others became rough due to the high pressure .


Combination of techniques: Plastic vacuum casting

P P i i lProcess Principle– Casting of a (RP)-master pattern in silicon rubber & reproduction

CharacteristicsCharacteristics– Very detailed reproduction– Undercuts are possible–Silicon rubber mold can be used severalSilicon rubber mold can be used several times–Suited for small lots < 50

Material– Various reaction resins (like Poly-Urethane)– Properties comparable to numerous plastics

Housing for drilling machineplastics

Max. part size & accuracy– 1000x1000x1000 mm3 max– Accuracy high Depends on master


Accuracy high. Depends on master.

Process chain for vacuum moldingProcess chain for vacuum molding

1 M t tt1. Master pattern2. Casting with silicon rubber under vacuum3. Cutting off of mold in parting plane4. Vacuum casting with reaction resin5. Curing under heat6. Removal of cast model11/11/2013 P Saha IIT Kharagpur 22

Reproduction with silicon moldReproduction with silicon moldsilicon rubber

ldmold

Cast part


2 Cast Metal Tooling2. Cast Metal Tooling

Sand casting– used for manufacturing relatively large tools in g y g

aluminium or cast iron for low pressure molding process. g p

– Requires final machining.


EOSSINT S 750L i t i t fLaser-sintering system for the direct, tool-less production of sand cores and moulds for

• Uses different corning sands which are used in foundries

• Light weight casting usingmetal castings

Light weight casting using Aluminum and Magnesium

• Also cast iron & steel


Cast Metal ToolingCast Metal Tooling

Rubber-plaster casting (and very infrequently investment casting) q y g)

– A silicon rubber copy of the required tool cavity is cloned from a master patterncavity is cloned from a master pattern.

– A plaster of paris is cast around the silicon rubber copyrubber copy.

– It is suitable for casting non-ferrous (Zinc or Al i i ) t l i tAluminium) tool inserts.


• Advantages– Conformal cooling is

possiblep– High integrity solid metal

tools are produced– Repair of tool is possible– With rubber-plaster casting

multiple tools can be produced from one master patternpattern

• Disadvantages– Machining and good

amount of manual polishing may be required.Diffi l h ld i hCast metal tools by rubber

plaster casting – Difficult to hold tight

tolerances with large tools


Bridge ToolingBridge Tooling • Bridge tooling is, a way to bridge the typical 12

- 14 weeks gap between design confirmation and actual part production with a hard tool.

• At this point in the production cycle, y– the design has been approved by sales and

marketing, the functionality has been checked by engineers, and

– now 200 to 2000 parts are needed in order to t bli h bl li h t b ildestablish assembly lines or perhaps to build

market interest.


• Bridge tooling methods may produce several hundred to as many as several ythousand parts in 1 to 6 weeks time.


Direct AIMTMDirect AIMDi t AIMTM t d f Di t ACES• Direct AIMTM stands for Direct ACES Injection Molding.

• Process of directly injection molding thermo-plastics p

• Core and cavity inserts are built with stereolithography using ACES build stylestereolithography, using ACES build style.

• These inserts can then be mounted into a prepared mold frame and s itable plasticsprepared mold frame, and suitable plastics can be injected directly.


• The highest glass transition temperature for an g g pstereolithography resin is about 100 0C. But these AIM inserts may withstand injection

0temperatures of about 300 0C.

Parameter LDPE HDPE PS PP ABS

I j ti 1600 2300 2400 1900 3200Injection pressure (psi)

1600 2300 2400 1900 3200

Injection temperature (0C)

180 220 200 205 240

Cycle time (minutes) 3.5 4.5 4.0 4.0 5.0


Direct AIMTM ProcessDirect AIM Process

The SLA insert fitted SLA cavities and core into the mould base inserts for AIM mould


Direct AIMTM ProcessDirect AIM Process

After the alloy solidified,Alloy of low melting point is After the alloy solidified, excess alloy is removed and ejector pins are added. The assembled mould is then

Alloy of low melting point is poured into the void at back side of the mould. Copper tube is placed in the void so assembled mould is then

installed on injection machine.

tube is placed in the void so that it will be embedded in the solidified alloy


Direct AIMTM ProcessDirect AIM ProcessAdvantages

–Fast Tooling - No other post-processing, like building p p g, gup parting surface and casting of silicone rubber is required.q

–Precision - Directly produced from the CAD model. Therefore the

Finished product and the SLA core

accuracy of the mould is only dependent on the accuracy of the SLA process. An accuracy of +/-0.05 mm is achievable.


Limitations of Direct AIMLimitations of Direct AIME i C d t th RT• Expensive - Compared to other RT processes of plastics mould, this is relatively expensive for the large size of the ACES mould.the large size of the ACES mould.

• Relatively weak in strength - Mould is quite fragile. Tool life is around 100 shots. g

• Poor thermal conductivity - Very long molding cycle is needed.

• Uncertainty - The process still needs quite a number of refinements before it can be widely applied in industryapplied in industry.

• Can be used for plastic parts only.


3 Metal Spray Tooling3. Metal Spray Tooling

Metal spray coating of zinc from SLA master (showing excellent(showing excellent replication detaail)

Arc spraying process

Spray forming p y gprocess for creating

thick steel shells


Metal Spray ToolingMetal Spray Tooling• Advantages

– Low Melting Point • Disadvantages

– Line-of-sight materials give excellent reproduction of master pattern

limitations – Low melting point

t l h li it dof master pattern surface.

– Process suitable for

metals have limited durability. Spraying of higherProcess suitable for

manufacture of relatively large tools

– Spraying of higher melting point materials is relatively complexis relatively complex process.


4. Nickel Vapor Deposition Technology

Ni + 4Co <-> Ni(CO)4 Heat at 110 -190 0C


Galvano FormingGalvano FormingIt i th d t d C d it i tIt is a method to produce molds quickly and cheaply is to use plastic plating

• Core and cavity inserts are built by rapid prototyping methods. p p g

technology. p yp g

• The inserts are plated with a 2 - 4 mm layer of i k l th t hnickel or other tough,

anti-corrosive metal. • The material is removed• The material is removed

by melting and draining, and the shell of a tool is fill d ithfilled with an epoxy bonded filler.


(A) Electroformed nickel (B) NVD nickel( ) ( )


Motivation behind Direct ToolingMotivation behind Direct ToolingT diti l h d t l d i i b th ti i d• Traditional hard tool design is both time consuming and costly. A large block of steel is typically CNC machined to create cores and cavity inserts. An experienced y pdesigner must machine the mold keeping in mind correct sprue placement, draft angles, vents, cooling lines, and ejection pin locations Fine details require EDMejection pin locations. Fine details require EDM. Polishing and grinding is usually required to achieve a good surface finish.

• If a mistake is made, the entire steel block may have to be scrapped and the process begins again. It ld b t i t t b bl t b ild• It would be most convenient to be able to build something as complex as a hard mold with something as efficient as rapid prototyping.


efficient as rapid prototyping.

Time savings with Rapid ToolingTime savings with Rapid Tooling


3D Systems’ KeltoolTM Process3D Systems KeltoolTM Process• Master pattern is built on a SLA machine• Master pattern is placed in a box.• Box is filled with RTV silicone rubber.• Extracting the master leaves a cavity• Extracting the master leaves a cavity.• Cavity is filled with mixture of powder metal and binder.

(normally tool steel/ tungsten carbide and expoxy ( y g ymixture.

• Green or week part is fired in a furnace. Binder burns off.• Copper is infiltrated into the space between remaining• Copper is infiltrated into the space between remaining

metal.• Finally we get a metallic duplicate of SLA master which

i 100% dis 100% dense.• The tool steel insert (70% tool steel, 30% copper is

ready for production)11/11/2013 P Saha IIT Kharagpur 45

eady o p oduct o )

3D Systems’ KeltoolTM Process3D Systems KeltoolTM Process

F tFeatures– Keltool inserts are restricted to about 6" in all

directions, which limits part size to about 4".– 3 weeks is typically required to turn around

the Keltool insert (plus time to prepare the SL pattern), as opposed to months to prepare a t diti l h d t ltraditional hard tool.

– Keltool can generate 50,000 to 1 million parts I j ti ldi hi d dion an Injection moulding machine, depending

on the injected material.


3D Systems’ KeltoolTM Process3D Systems KeltoolTM ProcessP P i i lProcess Principle

– Duplicate molding of SL-master patterns by long low temp. sintering

CharacteristicsCharacteristics– Very high hardness, stiffness and surface quality– Process chain two weeks

Material– Tool steel/ WC mixture infiltrated with copper

Max. part size & accuracy– 150x215x120 mm3 max– Tolerance +/- 0.2% Tool inserts made by Keltool

Facility Costs– System price approx. 200 000 US$


Process chain of Keltool processProcess chain of Keltool process

1. Master pattern2 Silicon casting2. Silicon casting3. Casting with tool steel/ WC/ epoxy mixture4. Burn out of binder, sintering and infiltration with copper4. Burn out of binder, sintering and infiltration with copper

in a furnace5. Tool insert ready for production


“Direct Tooling” DevelopmentsDirect Tooling - Developments

• Three Dimensional Printing – ExtrudeHone Corp. USA• RapidTool – 3D System USA • DMLS – EOS, Germany• LENS – Optomec, USA• EBM – Arcam, Sweden• Ultrasonic consolidation – Solidica, USA


3D Printing – Direct Metal Tools for Injection Moulding(Li d t E t d H C ti USA)(Licensed to ExtrudeHone Corporation, USA)

Injection molding tools and molded Metal tool with 3D truss structure for j gpart (conformal cooling) thermal isolation of injection mold cavity

A cooling Fast thermal response t li ith f l

gpassage printed conformable to the tooling cavity.

tooling with conformal cooling passages with a cellular/truss structure behind it for thermal isolation.


Indirect Metal Laser Sintering3D System’s “RapidTool” ProcessP P i i lProcess Principle

– Indirect selective laser sintering of metal powders–Burning out polymers and infiltrationBurning out polymers and infiltration with copper

Characteristics– Production of tool inserts for injection jmolding and die casting– Tool life upto 50000 shots

Material– Approximately 60% steel and 40% copper

Max. part size & accuracy380x330x440 mm3 max Tool insert– 380x330x440 mm3 max

– Accuracy +/- 0.1 mmFacility Costs

System price approx 275 000 US$

Tool insert


– System price approx. 275 000 US$

Process chain of “RapidTool” processProcess chain of RapidTool process

1. SLS of polymer coated steel powder2. Burning out binder & infiltration with copper2. Burning out binder & infiltration with copper3. Polishing and insertion into tool frame


M ld D i Th DTM R id T l P Infiltration & Furnace Treatment

3D System's “RapidTool” Process

Sinterstation 2000 System

Polymer Infiltration and Drying Oven

Mold Design The DTM Rapid Tool Process Infiltration & Furnace Treatment

CAD Workstation with

Green Part

Controlled atmosphere Furnace

3D Software for Part and Mold Design

Infiltration of Copper

Fully-Dense PartDebinding

Injection Molding

Injection Molding Machine

Polish and Integrate with Mold Base

50,000+ Finished Part


Injection Molding MachineFinished Part

Direct Metal Laser Sintering3D System’s “DirectTool” ProcessP P i i lProcess Principle

– Direct SLS of metal powder particles (DMLS)

CharacteristicsCharacteristics– Production of tool inserts for injection molding and die casting– No burn-out of binder required, qadvantages in accuracy and time

Material– Steel or bronze nickel, infiltration with

iblepoxy possibleMax. part size & accuracy

– 250x250x150 mm3 maxAccuracy +/ 0 1 mm DMLS insert in tool frame– Accuracy +/- 0.1 mm

Facility Costs– System price approx. 320 000 US$

DMLS insert in tool frame


Process chain of “DirectTool” processProcess chain of DirectTool process

1. SLS of meta powder directly2. Bronze or nickel powder: infiltration with copper2. Bronze or nickel powder: infiltration with copper3. Steel powder: not necessarily required4. Polishing and insertion into tool frame


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Rapid tooling process for injection moulding inserts

Batch Size10-200

Batch Size200-2,000

Batch Size2,000-20,000

StereolithographyCast resin

Cast resinMetal spraying

Metal sprayingGalvano forming

3D-KeltoolLaser sintering

3D-KeltoolLaser sintering g

(metal)Aluminum

g(metal)Aluminum and

Investment casting steel investment casting


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Rapid Tooling

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