Contents

57 Foot Plastic Boats — Research, Development, and Construction

Section Pages
Introduction 1

Process Investigations, Chronological Sequence

The Marco Method7
The Open Mold, Hand Layup Process10
The Wet Layup10
Layup With Preimpregnated Cloths11
Wet Layup With Thixotropic Resins12

Tests, Chronological Sequence

3" x 16" Panel Tests15
Water Transmission Tests17
5" x 20" Panel Tests18
Dow Chemical Co. Tests21
University of Michigan Tests22
New York Naval Shipyard Tests23
9" x 60" Panel Tests25

Basic Design Considerations

Basic Design Considerations 28

Local Design Details

The Hull Shell30
The Stem30
Deck Construction31
The Keel31
Internal Structural Components32
Bulkheads32
Longitudinal Girders33
Transverse Bracketing33
Walking Flats33
Bolting Provisions35

Tooling Development

The Male Plug37
The Female Mold38
Scaffolds and Staging41
Reference Location41
Molding of Internal Components43
Deck Molds43

Production of MSB-23 (First Boat)

Mold Preparation44
The Outer Skin44
Core Material and Internal Reinforcements45
The Inner Bonding Layer48
Internal Structural Components49
Bulkheads49
Girders49
Flats49
Deck Beams and Longitudinals50

Destruction By Fire

Destruction By Fire52

Interim Developments

Interim Developments53

Production of ExMSB-23 (Second Boat)

The Male Mold56
The Inner Skin57
Core Mat'l, Internal Reinf. and Outer Bonding Layer59
The Outer Skin and Stem Reinforcement61
The Keel62
Inversion and Mold Removal63
Installation of Internal Structural Components63
Deck Fabrication65
Installations and Outfitting68
Launching, Trials, and Delivery71

Quality Control

MSB-2373
ExMSB-2377

Materials

Materials81

Problems

Problems91

Conclusions

Conclusions97

Appendix A, List of References

Appendix A, List of References100

Appendix B, Test Data and Load-Deflection Curves

3" x 16" Panel Tests102
5" x 20" Panel Tests103
New York Naval Shipyard Tests, 99" Square Panels115
9" x 60" Panel Tests116

Appendix C, Comparison of Three Building Methods

Appendix C, Comparison of Three Building Methods143

Appendix D, Basic Strength Analysis

Appendix D, Basic Strength Analysis150

Appendix E, Photographs

Appendix E, Photographs177