ABYC Fiberglass Boat Repair Certification
Practice Exam Questions And Correct
Answers (Verified Answers) Plus Rationales
2026 Q&A | Instant Download Pdf
Covers all major domains: fiberglass composition, lamination, structural
repair, safety, standards, tools, and troubleshooting.)
1. What is the primary resin used in most fiberglass boat construction?
A. Phenolic resin
B. Polyester resin
C. Epoxy resin
D. Vinylester resin
Rationale: Polyester resin is the most common resin due to its low cost
and adequate mechanical properties for marine laminates.
2. Which material provides the primary strength in fiberglass laminate?
A. Resin
,B. Fiberglass reinforcement
C. Catalyst
D. Gelcoat
Rationale: Fiberglass fibers carry the load; resin primarily binds and
transfers stress between fibers.
3. Which type of fiberglass reinforcement offers the best multi-directional
strength?
A. Woven roving
B. Biaxial fabric
C. Chopped strand mat
D. Unidirectional cloth
Rationale: Biaxial fabrics combine multiple fiber orientations, improving
strength in more than one direction.
4. The gelcoat layer primarily provides:
A. Structural rigidity
B. Surface finish and UV protection
C. Chemical bonding
D. Electrical insulation
Rationale: Gelcoat protects from UV damage and creates a smooth,
aesthetic finish.
,5. What catalyst is typically used to cure polyester resin?
A. Benzoyl peroxide
B. Methyl ethyl ketone peroxide (MEKP)
C. Amine hardener
D. Acetone
Rationale: MEKP initiates polymerization in polyester resins.
6. Excess catalyst in resin causes:
A. Slower curing
B. Excessive exotherm and brittleness
C. Stronger bonding
D. No effect
Rationale: Too much MEKP raises curing temperature, making the resin
brittle and prone to cracking.
7. The ideal resin-to-glass ratio for hand lay-up is approximately:
A. 30:70
B. 40:60
C. 50:50
D. 60:40
, Rationale: A 40% resin to 60% glass ratio yields optimal strength and
minimal excess resin weight.
8. Air bubbles trapped in laminate cause:
A. Better flexibility
B. Weakness and delamination
C. Faster curing
D. No significant effect
Rationale: Voids reduce bonding and structural integrity.
9. When repairing structural fiberglass, the first step is:
A. Sanding
B. Damage assessment and isolation
C. Applying gelcoat
D. Cutting reinforcement
Rationale: Assessment ensures correct repair design and prevents hidden
structural issues.
10. Core materials in sandwich construction are used to:
A. Increase resin absorption
B. Increase stiffness without adding weight
C. Reduce adhesion
Practice Exam Questions And Correct
Answers (Verified Answers) Plus Rationales
2026 Q&A | Instant Download Pdf
Covers all major domains: fiberglass composition, lamination, structural
repair, safety, standards, tools, and troubleshooting.)
1. What is the primary resin used in most fiberglass boat construction?
A. Phenolic resin
B. Polyester resin
C. Epoxy resin
D. Vinylester resin
Rationale: Polyester resin is the most common resin due to its low cost
and adequate mechanical properties for marine laminates.
2. Which material provides the primary strength in fiberglass laminate?
A. Resin
,B. Fiberglass reinforcement
C. Catalyst
D. Gelcoat
Rationale: Fiberglass fibers carry the load; resin primarily binds and
transfers stress between fibers.
3. Which type of fiberglass reinforcement offers the best multi-directional
strength?
A. Woven roving
B. Biaxial fabric
C. Chopped strand mat
D. Unidirectional cloth
Rationale: Biaxial fabrics combine multiple fiber orientations, improving
strength in more than one direction.
4. The gelcoat layer primarily provides:
A. Structural rigidity
B. Surface finish and UV protection
C. Chemical bonding
D. Electrical insulation
Rationale: Gelcoat protects from UV damage and creates a smooth,
aesthetic finish.
,5. What catalyst is typically used to cure polyester resin?
A. Benzoyl peroxide
B. Methyl ethyl ketone peroxide (MEKP)
C. Amine hardener
D. Acetone
Rationale: MEKP initiates polymerization in polyester resins.
6. Excess catalyst in resin causes:
A. Slower curing
B. Excessive exotherm and brittleness
C. Stronger bonding
D. No effect
Rationale: Too much MEKP raises curing temperature, making the resin
brittle and prone to cracking.
7. The ideal resin-to-glass ratio for hand lay-up is approximately:
A. 30:70
B. 40:60
C. 50:50
D. 60:40
, Rationale: A 40% resin to 60% glass ratio yields optimal strength and
minimal excess resin weight.
8. Air bubbles trapped in laminate cause:
A. Better flexibility
B. Weakness and delamination
C. Faster curing
D. No significant effect
Rationale: Voids reduce bonding and structural integrity.
9. When repairing structural fiberglass, the first step is:
A. Sanding
B. Damage assessment and isolation
C. Applying gelcoat
D. Cutting reinforcement
Rationale: Assessment ensures correct repair design and prevents hidden
structural issues.
10. Core materials in sandwich construction are used to:
A. Increase resin absorption
B. Increase stiffness without adding weight
C. Reduce adhesion
