Raw materials and basic properties

      The raw materials are mainly divided into two categories: resin and glass fiber; the structure needs unsaturated polyester resin, and must have good waterproof and impact resistance. To be suitable for large-area operation and with good manufacturability, glass fiber uses a variety of materials, including surface felt, chopped felt, checkered cloth, composite felt cloth, reinforced core material, etc.

1. Glue shell (gel coat resin) is used in the appearance of FRP products, improve water resistance and weather resistance, and can keep the color from yellowing for a long time.
2. The laminated resin is used under the rubber shell, which is generally vinyl resin + o-phenyl resin.
3. The non-alkali surface felt is used between the gel coat resin layer and the load-bearing layer, which is easy to construct and ensures that the fiber traces of the felt cloth will not penetrate through the surface of the rubber shell.
4. Alkali-free chopped mat includes various types of chopped mat, woven mat and composite mat, which are good materials for contact molding.
5. Non-alkali checkered fabrics include thick and thin checkered fabrics of various models. In addition to the same characteristics, it can save resin usage and increase product strength.
6. Alkali-free composite felt cloth includes various types of composite felt cloth, which can increase strength and reduce product weight when molded except for the same characteristics.
7. Reinforced core materials include basa wood, PVC Form, honeycomb board, etc., which can reduce product weight and cost.

Construction method

      The general construction methods of glass fiber reinforced plastic yachts are roughly two types: hand lay-up method and vacuum adsorption method.

      The hand layup method is the basic construction method of FRP yachts. Most of them are the best construction methods for yachts under 60 feet. It is not easy to fail during construction, and there is no restriction on the appearance of the product. However, if the construction hull weight is inexperienced, it is not easy to control the best situation. As the name implies, the resin, felt and cloth are layered by hand, and the required construction period is relatively long. The hull, deck, flybridge and yacht all fiberglass accessories can use this method.

      Vacuum adsorption method is a relatively new process in recent years, and is generally used for the construction method of fast ships over 60 feet. The construction method is to place the glass fiber layer on the mold, lay the catheter and some auxiliary equipment, use vacuum bag and sealant to seal, and then vacuum the glass fiber layer, and then introduce the resin to form one time. Effective molding method. And save labor and time, light product quality, low porosity, less resin usage, increased strength and other advantages. However, there are also many disposable auxiliary materials needed, and the comprehensive cost calculation is comparable to the hand layup method. It is certain that the weight of the ship will be lighter. This construction method has not been used for many years, and the evaluation in the US yacht industry is still controversial.

Common fiberglass problems on yachts

      Common FRP problems include: cracking of rubber shells at structural joints, water leakage and water seepage at joints / openings, blistering of plastic shells on the surface of the FRP hull deck, or black spots, blisters on the deck, Cracking, leakage at the bottom of the ship, scratches and cracks during collision. And the color of the plastic shell on the surface of the glass fiber reinforced plastic will change color and produce color difference ... The reason may be negligence in manufacturing, or the abnormal condition of FRP caused by improper use.

The cause of the problem and the solution

      The problem often occurs on the surface of FRP and the reasons and different treatment methods are described as follows:

1. Discoloration, blistering and black spots on the surface of the shell:
due to the instability of the ratio of the curing agent at different times during local repair and construction, or the color difference of different batches of shells will cause the future of the shell Discoloration (dark and light color difference, yellow discoloration), especially on dark plastic shells.
Failure to completely exclude tiny air bubbles and dust particles during stacking will cause blistering and black spots on the external rubber shell in the future.
Treatment methods:
a. Color difference; polish off the surface rubber shell layer, recoat the same type of rubber shell, water grind to # 1000 or above sandpaper, and then polish and wax. The amount of curing agent should be controlled according to the manufacturer's recommendations during production and repair.
b. Foaming / black spots; chisel the shell layer at the foaming place / black spot, recoat the same type of plastic shell, water grind to # 1000 or above sandpaper, then polish and wax.
c. If there are deep blisters or black spots; it needs to be dug to the bottom, then fill the depression with crushed felt and build-up resin, and then recoat the same type of rubber shell after curing, and water grind to # 1000 or above The sandpaper is then polished and waxed.

2. Cracking at the joint between the hull and the deck:
Most of the accidents will occur at the joint of the side (hull and deck) due to accidental collision.
Treatment methods:
a. Local minor collision; remove the side fender bead to repair the glass fiber reinforced plastics, use structural glue and bolts to re-fix and then reinforce / repair.
b. Large area collision; please find a dealer to arrange professional repair.

3. Cracking of the surface rubber shell at the junction of the hull, deck, flybridge and glass fiber reinforced plastic parts:
most of them occur at the joint between the single-piece glass fiber reinforced plastic fittings such as stairs and Wet Bar and the main body of the deck. Due to the combination of two glass fiber reinforced plastic parts The corner part is easy to crack at the surface rubber shell due to long-term use.
Treatment method:
remove the excessively thick surface rubber shell layer, reinforce it with felt cloth and build-up resin. After curing, recoat with the same type of rubber shell, water grind to # 1000 or above sandpaper, and then polish and wax.

4. Deck surface area water:
Poor drainage on the deck surface or teak deck produces partial water accumulation.
Solution:
a. Local drain near the edge can add a drain.
b. Large area of ​​accumulated water must be rearranged surface drainage slope.

5. Bubbling of the scratch-proof board on the deck and cracking and water accumulation on the floor at the junction with the wall: the
bubble of the scratch-proof board is prone to occur after long-term use. The cracked water at the joint is generally caused by poor construction.
Solution:
a. Cut off the baffled scratch plate, and replace it with a new one with the same pattern. When repairing, pay attention to the continuity of the pattern.
b. Cracked water accumulation at the joint; chisel the cracked water accumulation part, and repair it again.

6. Leakage between the opening of the large window and the glass fiber reinforced plastic wall: the
general cause is leakage caused by deformation or poor construction of the large window after impact.
Solution:
a. Leakage of large window deformation; replace it with a new large window of the same model-please find a dealer to arrange a professional to deal with.
b. General leakage; first remove the wooden decorative bead in the cabin, re-glue the reinforcement and then install the decorative bead, the repair is completed.

7. Leakage between the porthole opening and the FRP hull:
Leakage caused by poor construction.
Solution:
first remove the wooden decorative bead in the cabin, re-glue and reinforce, and then install the decorative bead, repair is complete.

8. Leakage of equipment installation opening and glass fiber reinforced plastic body / floor:
due to construction negligence , leakage often occurs at the joint of hull / deck at the opening of various equipment installation, such as the import and export of engine and pulp shaft system, generator Intake and discharge ports, bow / stern thruster installation, related oil circuits / circuits / drain pipes, stabilizers, etc. are likely to occur throughout the hull deck.
Solution: The
above are all work in the field of professional technology and have security considerations. -Please find a dealer to arrange professional treatment.

9. Water leakage at the installation / opening of the
windlass : the windlass is above the chain warehouse. Poor installation causes water leakage to the windlass, which may penetrate the windlass motor and cause the windlass to malfunction. Or the drainage of the windlass opening is poor, which may cause water accumulation or flow into the anchor chain warehouse.
Solution:
a. Leakage of windlass installation; bolt fixing after reinstalling windlass.
b. Water leakage at the opening of the windlass; check the function of the drainage system and strengthen the drainage slope.

10. Minor leakage (Osmosis) on the surface of the bottom glass fiber reinforced plastic:
due to poor construction of the bottom of the hull, after the yacht is used for several years, small leakages in the local area or most of the area of ​​the bottom of the ship may occur. This slows down the cruising speed and causes premature aging of the FRP hull structure.
Solution:
Hang the yacht on the dock or dock for full inspection below the FRP waterline. -Please find a dealer to arrange professional treatment.

11. Leakage at the opening of the bottom of the ship:
the hull below the waterline has many inlets and outlets. If the construction is negligent or improperly used, it may also leak.
Solution:
Hang the yacht on the dock or dock for full inspection below the FRP waterline. -Please find a dealer to arrange professional treatment.

12. Scratches and cracks on the exterior of the FRP during an accidental collision:
Solutions:
a. Local minor scratches; if the scratches do not damage the FRP part, first remove the surface rubber shell, fill the depressed area with soil, and recoat On the same type of rubber shell, water grind to # 1000 or above sandpaper and then polish and wax. 
b. If the scratches have damaged the glass fiber reinforced plastic part; first remove the surface plastic shell, then use glass fiber crushed felt and build-up resin to fill in the recessed area, and after the curing is completed, recoat the same type of plastic shell and water mill to # 1000 Or above sandpaper is then polished and waxed.
c. Cracking occurred during
the collision ; this is a crack caused by a severe collision, and safety has been involved. -Please find a dealer to arrange professional treatment in time.

Simple maintenance method of fiberglass yacht

• Daily cleaning and care-remove seawater and dirt accumulated on the surface, keep it dry at any time.
• Regular waxing and polishing – keep the surface of the FRP bright and protect the rubber shell.
• Treat scratches in time – avoid leakage.
• Avoid long-term sun exposure-when not in use, cover the FRP instrument panel and the driving chair / whole boat on the fly bridge with a canvas cover / boat cover. Pack the yacht on the shore in winter.
• Drive the correct mooring carefully – use anti-collision balls when the boat is docked ... wait for the implementation, avoid direct contact with stones, concrete structures, metal parts on the shore, etc.
• User's Manual – Carefully reading the owner's manual is the most effective method for yacht maintenance.