1. TCA and Contributions Made to Improve SMC Paintability
Mike Siwajek
ThyssenKrupp Budd Company
Society of Plastics Engineers
Automotive Composites Conference
September 9-10, 2003
Troy, MI

2. Goals and Objectives

3. Defect Root Cause Analysis
500+ defects from 10 assembly plants catalogued
Large percentage of defects due to microcracks from handling
Majority of “handling” defects occurred after primer application

4. Root Cause Breakdown
Cracks &
damage

5. Toughening the Matrix Targeting edge defects Evaluate all components
resins
fillers
LPA’s
additives
catalysts / inhibitors
glass

6. Improved Toughness
TCA
Control

7. Paint Pop Flex Test 2 x 18 x 0.1 test strips
8.25 diameter cylindrical mandrel
designed for 125% of ultimate stress
deformation creates micro-cracks on SMC surface
Paint with conventional Primer-sealers using E-coat bake simulation (380F for 30 min.)
count “paint pops” on surface of SMC

8. PP Flex Test Panels
Control
Tough Class ‘A’

9. Verifying TCA’s Effectiveness
Multiple DOEs performed
Ford Paint on Plastics Team / 6-sigma black belts
AOC
Red Spot
Studied effects of
SMC type
Humidity
E-coat
Stress after molding (molding plant damage)
Stress after priming (body shop handling damage)
Type of primer (standard 2K and UV Thermal)

10. TCA DOE Results TCA less affected than control
Sample Paint Pop Test Results
TCA less affected than control
humidity
temperature
handling extremes
90+% improvement in pop resistance over control
Desired

11. TCA Implementation TCA has afforded:
Conversion from double layer of primer to single layer of primer without degradation in quality
Up to 98% reduction in paint defects
Currently less than 10 defects submitted for microscope analysis (since May 2002) - Zero Microcracks

12. Ford Sport Trac
Process DOE completed in May 2002 (defect rate reduced to ~60)
Full conversion to TCA in June 2002
Defect rate has dropped from ~60 to below 10

13. Ford T-Bird Defect rate includes all parts fender converted July 2002
decklid 07/29/02
hood 09/2002
Level defect rate for TCA 1X primed vs standard SMC 2X

14. Ford Ranger Hood Full conversion to TCA 08/13/02
Defect rate dropped from ~200 to nearly 0
Pop rate data collection suspended by assembly plant
Conversion to TCA

15. Lincoln Navigator Hood
Converted hood to TCA on 06/17/02
Level defect rate for TCA 1X primed vs. standard SMC 2X

16. Lincoln Navigator Fenders
Converted fenders to TCA August / September ‘02
Level defect rate for TCA 1X primed vs. standard SMC 2X

17. Paint pop Data Collection Suspended
Ford Mustang Hood
Terminator, GT Hoods and Decklid converted to TCA
Defect rate reduced to 0-20
Mach 1 launched with TCA
Paint pop Data Collection Suspended
by Assembly Plant

18. Paint pop Data collection suspended
Ford Mustang Decklid
Paint pop Data collection suspended
by assembly plant

19. Ford Econoline Hood
Converted to TCA February 2003
Conversion to TCA

20. What next??? Remove the Class ‘A’ SMC Stigma at OEMs
Tough Class ‘A’
UV Thermal Primer
New primer-sealer technologies
SMC Consistency Program
Best practices (compounding and molding)
Defect traceability
Eliminate variability

21. SMC Consistency Improvement Plan
Target programs for improvement
Identify Key Performance Criteria (KPCs)
as defined by customer (molding plant or OEM)
Target broad cross-section of causes for inconsistencies (Control Factors / CFs)
Form cross-functional teams to focus on this effort
Stepwise regression of defects vs. CFs
Develop a sound engineering basis for the effort

22. SMC Consistency Roadmap
Data Analysis - identify
Data Gathering
possible CF's
Brainstorm - understand
failure mode
failure
mode
identified ? no
yes
Conduct experiments to
Implement in production
verify failure mode
Establish CF statistical
Data Gathering to verify
capability
improvement

23. Acknowledgements
SPE
Ford GPE
AOC
Red Spot
TK-Budd Team