MST MST Hull & Fiberglass Repair 3

Question 1

When fairing a hull repair, fairing compound should be applied in how many thin layers?

Accepted Answer

Multiple thin coats, allowing each to cure

Answer

Multiple thin coats prevent shrinkage cracking and allow proper cure between applications for a durable, fair surface.

Question 2

Which safety precaution is most critical when working with MEKP catalyst?

Accepted Answer

Wear chemical splash goggles and nitrile gloves

Answer

MEKP is highly corrosive to eyes and skin, requiring chemical splash goggles and nitrile or neoprene gloves at all times.

Question 3

What is the recommended approach for repairing a through-hull fitting that has corroded and is leaking?

Accepted Answer

Haul the vessel and replace the fitting with a properly sized bronze or composite unit

Answer

A corroded through-hull is a serious safety risk and must be replaced with a properly rated fitting after hauling the vessel out of the water.

Question 4

What tool is used to cut out a damaged section of fiberglass hull cleanly for a patch repair?

Accepted Answer

Oscillating multi-tool or rotary cutter

Answer

An oscillating multi-tool or rotary cutter allows precise, controlled cuts in fiberglass without excessive vibration or cracking adjacent laminate.

Question 5

What causes print-through on a fiberglass hull, where the weave pattern is visible through the gel coat?

Accepted Answer

Insufficient gel coat thickness over the fiberglass weave during original lay-up

Answer

Print-through occurs when gel coat is applied too thinly or the weave pattern telegraphs through during cure and shrinkage.

(MST) Marine Service Technician Practice Test