Yamaha 2014 Hull Repair Guide 90894-64680-42 - HullRepair

 

Hull Repair Manual

90894-64680-42

 

PREFACE FRP (Fiberglass Reinforced Plastic) has been widely used in various sectors of the industry. It is lightweight and free of corrosion, requiring no special care. After a long period of use, however, it may develop scratches or cracks. Such blemishes can easily be repaired, if you have the correct knowledge of FRP. With this in mind, we have prepared a manual with the aim of familiarizing you with the characteristics of FRP. Please keep this manual at hand so you can make full use of it as a readily available reference material. Yamaha Motor Co. Ltd.

Important information Particularly important information is distinguished in this manual by the following notations:  : This is the safety alert symbol. It is used to alert you to potential personal injury hazards. Obey all safety messages that follow this symbol to avoid possible injury or death.

A WARNING indicates a hazardous situation which, if not avoided, could result in death or serious injury.

A NOTICE indicates special precautions that must be taken to avoid damage to the outboard motor or other property. property.

TIP: A TIP provides key information to make procedures easier or clearer.

 

Basic Knowledge of FRP What is FRP? FRP stands for Fiberglass Reinforced Plastic. It is a composite material in which a woven fiberglass is impregnated with resin and then laminated, and allowed to cure into a rigid state.

Characteristics of FRP FRP has the following characteristics:  High strength strength yet yet light weight weight • Excellent Excellent mallea malleability bility • Corrosion Corrosion free • Easy to care for and easy to repair. repair. On the other hand, it is liable to get scr scratched atched during beach landings and is vulnerable to shocks coming from protruding objects such as rocks in water and, therefore, must be handled with care.

Manufacturing process Yamaha has employed several different processes in the manufacture of Yamaha Water Vehicles and jet boats including SMC (Sheet Molding Compound), HLF (Hand-Laid Fiberglass), and RTM (Resin Transfer Molding). For Water Vehicles, SMC molding process is employed. The outer surface is coated with urethane paint, and the inner surface is smooth but dull colored. On the other hand, HLF process is employed for jet boats. The outer surface of an HLF and RTM product consists of a gelcoat layer just like a boat hull. The inner surface, however, is a smooth thin layer made up of chopped brown fiberglass. RTM products use the same materials as those of HLF products. SMC molding process: A dough-like sheet of fiberglass and resin is first placed on a male mold, a female mold is placed on the sheet, and high pressure is applied to the mold at temperatures of 130–140 °C (266–284 °F), and then allowed to cure. Thereafter, Thereafter, the outer surface of the sheet is urethane painted.

Sheet of fiberglass and resin mixture

Pressed by the mold under high pressure Painting Demolding

Mold RTM molding process: First, the fiberglass mat is preformed so it fits a mold. Next, this preform is placed in a female mold coated with sprayed gelcoat, and then a male mold is placed on top. Thereafter, polyester resin is injected under high pressure into the gap between both molds. Male mold

Preform

Demolding

Female mold

Gelcoat

1

Injecting with resin

 

Difference in repairing methods The most appropriate repair method for the product depends on the type of manufacturing process used, SMC, RTM, or HLF. Depending on the repair method, the material to be used such as resin or coating differs. It is important to select the most appropriate method for the product you are going to repair.

 

• The urethane paint layer is softer and thinner than gelcoat paint layer. Therefore, special care should be exercised when polishing. • Roving cloth and mat are not used for repairs using epoxy resin. The binder that holds the mat together is dissolved by the styrene in polyester resins. Epoxies don’t contain styrene as a diluent. Additionally, if lamination was performed using roving cloth, the space between each layer is filed with epoxy resin, causing interface delamination and separation of roving cloth. Water Vehicles Manufacturing process Resin Paint Fiber materials for repairs Thickness of surface painting

Jet boats

SMC

RTM, HLF

Epoxy resin Urethane paint Gl a as ss cloth, chopped strand

Polyester resin Gelcoat paint/urethane paint Mat, rovi n ng g cloth

0.02–0 0.0 2–0.04 .04 mm mm (0.000 (0.0008–0 8–0.00 .0016 16 in)

0.3–0. 0.3–0.5 5 mm (0.01 (0.01–0. –0.02 02 in) in)

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*SMC includes NanoXcel

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Before Repair

The following warnings should be observed because chemical agents used in the repairs are flammable and may be hazardous to the health of the repairer. • Before using the resins and solvents, read the manufacturer's instructions, safety precautions, and warnings thoroughly. thoroughly. • Do not use the resins and alcohol near fire. Do not bring open fire, sparks and sources of ignition into the work area because the resins and alcohol are flammable. • When sandpapering and disk-sanding, the repairer should wear coveralls (or long sleeved work clothes), dust protective mask, safety goggles, working gloves. When using the resins, alcohol or an organic solvent, the repairer should wear coveralls (or long sleeved work clothes) and rubber gloves. • Carry out the repairs in a well-ventilated place. Avoid breathing resin vapors. • Should any solvent spill on your skin, immediately wash it off thoroughly with soap and water. • Do not work in the rain.

Obtaining the best results 1. Do not dampen fiberglass. fiberglass. Dampened Dampened fiberglass cloths and mat will not absorb resins resulting resulting in imperfect hardening and adhesion. Additionally, Additionally, this will affect the ability to completely wet out and remove air from the repair. Therefore, fiberglass should be kept clean and dry. 2. Keep all of the repair materials in a clean, cool, dry and dark area. Resin Resin will not fully cure on wet materials. It is advisable to carry out repairs on a relatively low humidity day. Temperatures most suitable for repair are between 20–30 °C (68°–86 °F). 3. The area to be repaired should should be free of dust and and grease. Resin will not adhere to dusty dusty or greasy area. 4. Different products vary vary in curing time. time. This can can be as short short as 5 minutes minutes and as long as 20–30 minutes. Have Have all materials ready to apply in accordance with the product used.

Tool cleaning Immediately after using the mixed resins, clean the tools (e.g., brush, squeegee, and defoaming roller) using the following procedure. Perform this cleaning procedure before the agent on them hardens (even if the repair is not yet completed). Refer again to the Warning given in “Before Repair” before carrying out the following cleaning: 1. Put an acetone acetone solvent solvent in in the bucket bucket and place the tools in it. 2. Remove Remove resin from the tools first by scrubbing the tools with each other and then by hand with gloves. 3. Wipe Wipe tool tools s with with a clot cloth. h.

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Disposal of remaining agents Dispose of the remaining resin mixture, putty, paint, and cardboard used for mixing the agents in accordance with the local ordinances or codes.

Do not dispose of the agents without observing the local ordinances or codes. Burning the agent produces a poisonous gas.

 

Workshop cleaning After the repair is completed, clear the tools and unused chemicals from the work area. Close the containers of resins, filler and paint tightly. tightly.

TIP: These agents harden/deteriorate on contact with fresh air.

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SMC Repair For repairs on Yamaha Water Vehicles, an epoxy resin should be used. The explanations on repairing procedures in this manual are given using a recommended resin material. * WEST SYSTEM resin products are recommended for repairs.

Materials and tools required Degreasing Resin Fibe Fiberr ma materi terial als s Defoaming tool Fina Finall fini finish shin ing g Cleaning Materials:

IPA (i (isopropyl al alcohol) Epoxy resin, hardener Gla lass ss cl clot oth, h, cho choppe pped st strand, and, fille illers rs Brush Uret Uretha hane ne pai paint ntin ing, g, sa sand nd-p -pap aper erin ing g and and com compo poun und d poli polish shin ing g Acetone

Glass cloth Glass cloth consists of continuous twisted strands of glass combined to form a woven fabric. Fiberglass thickness of glass cloth is categorized by the fabric weight (g) per 1 square meter which is indicated as a part of the product number. The thickness of a piece of resinimpregnated impreg nated glass clot cloth h is about 0.1 mm (0.004 in) ffor or #100 #100,, and about 0 0.25 .25 mm (0 (0.01 .01 in) for #200. It is recommended to use #100 or #200 for repairs. Chopped strand Chopped strand mixed with resin is used as a reinforcing material in areas where forming cannot be performed using glass cloth or areas where greater strength than paste is required. Used in areas where glass cloth cannot be attached or forming cannot be performed using glass cloth. Smooths repaired surfaces. Consistency

Un th th ic icke n ne ed mixt u urre SYRUP

Sl ig ig h htt ly ly t h hii ck cke n ne ed KETCHUP

Mo d de erat rate lly y th ic icke n ne ed MAYONNAISE

Ma x xii m mu u m th iic ckne s ss s PEANUT BUTTER

General appearance

Characteristics

Uses

Drips off off vertic cal al su surfac rfaces. es.

Sag Sags s dow down n ve vertical rtical surfaces.

Clings to vertical surfaces, peaks fall over.

Clings to vertical surfaces, peaks stand up.

Coating, “Wetting “Wetting-out” -out” before bonding, applying fiberglass, graphite and other fabrics

Laminating/bonding flat Laminating/bonding panels with large surface areas

General bonding, filleting, hardware bonding

Gap filling, filleting, fairing, bonding uneven surfaces

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Epoxy resin (105 Epoxy Resin) This is the resin normally used in SMC repairs. Epoxy resins give good adhesion to SMC. Additionally, epoxy resins have less viscosity compared to polyester resins and thus permeate easily, making defoaming process easier.

 

Hardener Epoxy resins are cured by the addition of hardener. The mixing ratio of resin and hardener is 5 : 1. This quantity may be altered slightly, however, excessive amounts may cause discoloration, deformation, air bubbles, and brittleness. On the other hand, too little will cause under cure. Additionally, the cure speed varies depending on the temperature and the hardener. Select the most suitable hardener for your repair work. In general, 206 is commonly used. The type of hardener to be used depends on the type of the resin. Make sure to use the correct type of hardener for the resin and refer to the product specification sheet for the correct mixing ratio.

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H AR AR DE DEN ER ER T EM EM PE PER AT ATU RE RE RA NG NG E HARDENER

U SE S Re sin/Hardener

Room Temp. 4.4 (40)

10 (50)

15.6 (60)

Fast cure:

205 206

General bonding, fabric application and barrier coating Slow c ure: General bonding, fabric application and barrier coating

21 (70)

26.7 ( 80)

C UR UR E SPEEDS at room temp.

°C (°F) 32 (90)

37.8 (100)

POT LIFE 100g 100 g cupful

WORKING TIME thin film

CURE TO SOLID thin film

9–12 minutes

60–70 min utes

6–8 hours

20–25 minutes

90–110 min utes

10–15 hours

TIP: For bonding applications, use a shallow and wide container to retard self-heating and extend the working time. Conversely, using a deep, small container accelerates self-heating and shortens the working time.

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IPA (isopropyl alcohol) IPA is used to degrease SMC surface before applying laminations because IPA has less effect than acetone on urethane paint.

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Acetone Acetone may be used to remove oil and stains, clean tools, and in general clean up. Excessive use of acetone on surfaces may remove or deteriorate the gloss and texture.

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Filler (407 Low Density Filler) The filler is low density powder made from glass microballoon. This is mixed with epoxy resin and used as paste. This paste is used to fill small gaps or bond reinforcement materials.

Consistency

Un th th ic icke n ne ed mixt u urre SYRUP

Sl ig ig h htt ly ly t h hii ck cke n ne ed KETCHUP

Mo d de erat rate lly y th ic icke n ne ed MAYONNAISE

Ma x xii m mu u m th iic ckne s ss s PEANUT BUTTER

General appearance

Characteristics

Uses

Drips off off vertic cal al su surfac rfaces. es.

Sag Sags s dow down n ve vertical rtical surfaces.

Clings to vertical surfaces, peaks fall over.

Clings to vertical surfaces, peaks stand up.

Coating, “Wetting “Wetting-out” -out” before bonding, applying fiberglass, graphite and other fabrics

Laminating/bonding flat Laminating/bonding panels with large surface areas, injecting with a syringe

General bonding, filleting, hardware bonding

Gap filling, filleting, fairing, bonding uneven surfaces

Tools: The following tools are required. • Scis Scisso sors rs For cutting glass materials • Tapes and paper paper for for masking • Blade of of utility utility knife knife For trimming glass prior to full cure

• Pure bristle bristle brush, spatula, squeegee For impregnation of glass materials, mixing/applying resins, and removing air bubbles

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• Grindi Grinding ng tools tools May include grinding discs, disc sander, files, sanding blocks, etc. • Spray Spray gun For urethane paint

 

• Electric Electric polisher polisher For finish buffing

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• Sandpaper Sandpaper and sandin sanding g discs #40–#120 grit • Waterproo Waterprooff sandpaper sandpaper #400–#1200 grit For finish sanding

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• Graduated Graduated measur measuring ing cups Measuring of resin and hardener • Contai Container ners s For mixing of resin and washing of tools. Using a disposable container is recommended. • Weighing Weighing instru instrument ment For measuring glass cloth weight

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• Dust protective protective goggles, coverall

mask, mask,

gloves, gloves,

safety safety

SMC material life Hardeners and epoxy resins will deteriorate after extended periods of storage and will, therefore, not cure properly. Typical shelf life is as follows: Material Epoxy resin Hardeners

Life 3 to 6 months 1 year

Conditions of storage These values apply to temperatures of 25 °C (77 °F) or lower and in a cool, dr y area, not in direct sunlight. Keep all containers clean and tightly closed when not in use.

Repair chemicals can be flammable. Follow manufacturer's instructions for proper storage. Do not store in vicinity of fire or open flames.

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Types of damage Types of SMC damage are shown below. Repair procedures will vary accordingly. accordingly.

 

Examples of damage: Scratches on painted surface Polish the painted surface using the compound. The thickness of urethane painted surface is 0.02–0.04 mm (0.0008–0.0016 in). Use extreme care as too much sanding will

Urethane painting

SMC

remove all the urethane painting and new painting will have to be applied.

3

Deep scratches reaching SMC Repair using chopped strand instead of constructing lamination depending on the depth of SMC repair.

Urethane painting

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SMC

5 Damage (hole) to the SMC Repair with lamination.

Urethane painting

SMC

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Deep scratches reaching SMC Repair area:

Procedure: 1. Polis olishi hing ng Polish the repair area using a sander. Remove the damaged area, making sure that the damages in SMC such as cracks, frayed edge, or whitened surface is eliminated completely.

2.

Degr egreasi easin ng After degreasing the polished area with IPA, allow it to dry throughly.

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3. Prepar Preparati ation on of epoxy epoxy resi resin n Weigh glass cloth and determine the required amount of epoxy resin. This will avoid a shortage of epoxy resin during the repair work.

 

Amount of epoxy resin = Weight of total glass cloth  2 Weight of total glass cloth (g) 50

Amount of epoxy resin (cc) 100

100 150 200

200 300 600

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4. Addi Additi tion on of har harde dene ners rs The mixing ratio of epoxy resin and hardener is 5 : 1. Thoroughly stir the mixture.

Hardener

1

Epoxy resin

5

TIP: For best results, the hardener used with the epoxy resin should be the one that is most suitable for the working time and working conditions. For details, refer to “Hardener”. “Hardener”.

5.

4 5

Masking Outline the area to be repaired with masking tape to minimize mess and work.

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6. Applying Applying epoxy epoxy resin/hard resin/hardener ener mix Apply a thin coat of epoxy resin/hardener mix to the repair surface.

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7. Addi Adding ng chop choppe ped d stran strand d Put epoxy resin/hardener mix in a separate container, add chopped strand, and mix them. (Consistency: Mayonnaise)

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TIP:

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Chopped strand is used on the areas where forming cannot be performed using glass cloth or areas where greater strength is required.

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8. Formi Forming ng the the repa repair ir into into shap shape e Apply chopped strand to the repair surface and form it into shape. Make sure that the surface of the applied chopped strand is higher than the original hull surface.

9. Appl Applyi ying ng gla glass ss clo cloth th To achieve better adhesive strength, cover the chopped strand with glass cloth. Apply epoxy resin/hardener mix using a br ush, avoiding entrapment of air. After applying the epoxy resin/hardener mix, leave it overnight to cure. For details, refer to “Hardener”. “Hardener”. 10. Removing Removing maskin masking g Once the epoxy resin/hardener mix is hardened, remove the masking. 11. Surface Surface treatment treatment After the chopped strand and glass cloth is completely cured, smooth the surface using #80 sandpaper. sandpaper.

12. Degrea Degreasin sing g After degreasing the polished area with IPA, allow it to dry throughly. Remove sanding dust and degrease the surface completely. 13. Mixing Mixing of paste paste Put epoxy resin/hardener mix in a separate container, add filler, and mix them. (Consistency: Peanut butter)

TIP: Once smoothed out, the surface will have many tiny pin holes which will trap air when applying the urethane paint. A paste may be applied and then sanded smooth prior to urethane paint application to eliminate these holes. Avoid application of automotive body fillers as these tend to shrink and/or crack.

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14. Applying Applying paste paste After applying the paste, leave it overnight to cure.

  15. Surface Surface treatment treatment After the paste is completely cured, smooth the surface using #80 sandpaper. sandpaper.

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16. Degrea Degreasin sing g After degreasing the polished area with IPA, allow it to dry throughly. Remove sanding dust and degrease the surface completely.

4

17. Applying epoxy resin/hardener mix Apply a thin coat of epoxy resin/hardener mix to coat the repair surface. After applying the epoxy resin/hardener mix, leave it overnight to cure. For details, refer to “Hardener”. “Hardener”.

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18. Surface Surface finishin finishing g Wet the surface with water and sand the coated patch area with #320–800 grit waterproof sandpaper, and then wipe down with a clean, dry rag.

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19. Urethane Urethane paint For urethane painting procedures, refer to “Urethane painting”. painting”.

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Damage (hole) to the hull Repair area:

Procedure: 1. Marking Mark the area of sanding (scarfing) with tape or marking pen. The width of scarf (from the edge of the broken area to the edge of scarfing) should be 12 times larger than the hull material thickness.

Scarfing In general, for repairs using epoxy resins, the width of scarf should be 12 times larger than the hull material thickness.

TIP: Scarfing making a scarf along the the edge of means the broken area to ensure adhesive area. The larger the adhesive area, the greater the adhesive strength. Thickness of hull

Example: Thickness of hull (4 mm [0.16 in])  12 = Scarfing (48 mm [1.89 in]) Thickness of hull [mm (in)] 2 (0.08) 4 (0.16) 6 (0.24) 8 (0.32)

Width

Width of scarfing [mm (in)] 24 (0.94) 48 (1.89) 72 (2.83) 96 (3.78)

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of scarfing

 

Width

of scarfing

 

2. Sand Sandin ing g (Sca (Scarf rfin ing) g) Make a scarf. While sanding the surface, thoroughly smooth out the broken area at the same time. Make sure all delaminated material has been removed. After scarfing, clean the sanded area with a rag or brush.

3.

 

Degr egreasi easin ng After degreasing the polished area with IPA, allow it to dry throughly.

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4. Preparing Preparing a reinfo reinforcing rcing back back plate plate Place a glass cloth (2 ply) on a flat surface and apply the epoxy resin/hardener mix to the cloth until it penetrates the cloth throughly. The piece of glass cloth must be larger than the hole in the hull.

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TIP: Another option is to make a template by placing the cloth on the hull surface.

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Once it is cured, cut it to a size a little larger than the hole in the hull.

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5. At Attac tachin hing g the the back back plate plate Remove any moisture within the urethane layer. Make a space between the urethane layer and the hull for installing the back plate.

Hull

Back plate

Urethane layer

If there is no urethane layer, attach a handle to the center of the back plate using a screw or the like, and pull up the handle so that the back plate is firmly adhered to the hull. Use epoxy adhesive, if necessary, when adhering the back plate to the hull.

Hull Screw

Epoxy adhesive Back plate

6. Cutt Cuttin ing g glas glass s clot cloth h Cut glass cloth in the proper size for lamination. Before cutting, verify the construction of lamination. The first-laid glass cloth should be 5 mm (0.2 in) larger than the repair area at one side. The glass cloth to be placed next should be 5 mm (0.2 in) smaller smaller than the first first laid glass cloth at one side. Prepare the necessary number of glass

mm (in) 5 (0.2)

cloths so that the thickness of the cloth is the same as the thickness of the hull to be repaired.

First-laid glass cloth

Thickness of hull = thickness of glass cloth  number of glass cloth Thickness of hull (mm) 1 2 3 4 5

5 (0.2)

Number of glass cloth #100 #200 10 4 20 8 30 12 40 16 50 20

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7. Prepar Preparati ation on of epoxy epoxy resi resin n Weigh glass cloth and determine the required amount of epoxy resin. This will avoid a shortage of epoxy resin during the repair work.

 

Amount of epoxy resin = Weight of total glass cloth  2 Weight of total glass cloth (g) 50

Amount of epoxy resin (cc) 100

100 150 200

200 300 600

3

8. Addi Additi tion on of har harde dene ners rs The mixing ratio of epoxy resin and hardener is 5 : 1. Thoroughly stir the mixture.

Hardener

1

Epoxy resin

5

TIP: For best results, the hardener used with the epoxy resin should be the one that is most suitable for the working time and working conditions. For details, refer to “Hardener”. “Hardener”.

4 5

9. Applying Applying epoxy epoxy resin/hard resin/hardener ener mix After degreasing the sanded surface and reinforcement back plate, apply epoxy resin/hardener mix.

6 7

10. Adding Adding chopped chopped strand strand Put epoxy resin/hardener mix in a separate container, add chopped strand, and mix them. (Consistency: Mayonnaise)

8

TIP:

9

Use chopped strand to increase the strength of patched hole and smoothen the repair surface.

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11. Applying Applying chopped chopped strand strand Apply chopped strand so that the glass cloth attachment surface becomes smooth.

12. Maskin Masking g Outline the area to be repaired with masking tape to minimize mess and work. 13. Applying Applying glass glass cloth cloth As shown in the lamination construction diagram, start the lamination by placing a cloth that is large enough to cover the scarfing first. Lay the glass cloth correctly, let it adhere thoroughly, then permeate it with the epoxy resin/hardener mix using a brush.

Construction of lamination As shown in the figure, laminate glass cloth layers. Prepare 2 pieces of glass cloths of the same size. The glass cloth to be placed next should

mm (in)

Glass cloth

be 5 mm (0.2 in) smaller than than the first laid glass cloth at one side.

14. Removing Removing bubbl bubbles es Using a brush, remove trapped air bubbles carefully from the applied glass cloth. Any remaining air will cause layer separation. Do not allow epoxy resin/hardener mix to dry between lamination layers. Another option is to attach l aminated layers of glass cloths, which were prepared separately, to the repair area.

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5 (0.2)

 

15. Completio Completion n of lamination lamination By repeating the above procedure, laminate the necessary number of glass cloths. The glass cloth on top must be higher than the surface of the hull to be repaired. After completing the lamination, leave it overnight to cure. For details, refer to “Hardener”.. “Hardener”

 

16. Removing Removing maskin masking g Once the epoxy resin/hardener mix is hardened, remove the masking.

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17. Surface Surface treatment treatment After the lamination is completely cured, smooth the surface using #80 grit sandpaper.

4 18. Degrea Degreasin sing g After degreasing the polished area with IPA, allow it to dry throughly. Remove sanding dust and degrease the surface completely.

5 6

19. Mixing Mixing of paste paste Put epoxy resin/hardener mix in a separate container, add filler, and mix them. (Consistency: Peanut butter)

7

TIP: Once smoothed out, the surface will have many tiny pin holes which will trap air when applying the urethane paint. A paste may be applied and then sanded smooth prior to urethane paint application to eliminate these holes. Avoid application of automotive body fillers as these tend to shrink and/or crack.

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20. Applying Applying paste paste Apply paste to the surface to be repaired and flatten out using a spatula. Wipe off excessive paste with IPA. After applying the paste, leave it overnight to cure.

21. Surface Surface treatment treatment After the paste is completely cured, smooth the surface using #80 sandpaper. sandpaper. 22. Degrea Degreasin sing g After degreasing the polished area with IPA, allow it to dry throughly. Remove sanding dust and degrease the surface completely.

23. Applying epoxy resin/hardener mix Apply a thin coat of epoxy resin/hardener mix to coat the repair surface. After applying the epoxy resin/hardener mix, leave it overnight to cure. For details, refer to “Hardener”. “Hardener”.

24. Surface Surface finishin finishing g Wet the surface with water and sand the coated patch area with #320–800 grit waterproof sandpaper, and then wipe down with a clean, dry rag.

25. Urethane Urethane paint For urethane painting procedures, refer to “Urethane painting”. painting”.

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Urethane painting Air compressor adjustment: Drain any water from the air compressor (tank and air filter), and adjust the air pressure to 2–3 kgf/cm2.

 

Procedure: 1. Masking Mask the surrounding areas to prevent adhesion of the paint.

TIP: Wipe the surface with a lacquer thinner. For SMC plastics, lacquer thinner gives the paint better adhesive strength than acetone.

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2. Spra Sprayi ying ng surf surfac acer er Surfacer has the following effects: • Removes Removes traces traces of sanding sanding • Improves Improves adhesion strength of paint • Prevents Prevents the color of primer from having influence on the top coat.

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3. Uret Uretha hane ne pai paint nt Hold a spray gun at right angles to and 30 cm (11.8 in) off the surface to be sprayed. Spray urethane paint at a steady speed. (Avoid spraying outdoors, if windy.)

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4. Surf Surfac ace e trea treatm tmen entt Damp #600 grit waterproof sandpaper with water and lightly polish the surface.

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5. Surf Surfac ace e fini finish shin ing g Coat the polished surface with compound, and while smoothing out the trace of sandpapering, finish the surface. Avoid polishing the same area too much or paint will soften and peel off.

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Examples of repair Broken parts and debonding parts When any part has debonded or broken, the portion of the part remaining on the hull should be thoroughly removed so repairs can be done by bonding in a new part. Procedure: 1. Remove Remove the remaining remaining portion portion of the broken part and bonding agent by sanding the hull. Use of an abrasive Sanding

grinder will greatly speed up the process. 2. Thoroughly Thoroughly clean the sanded sanded surfa surface. ce. Coat the hull with the specified epoxy resin/hardener mix, and place two glass cloths, which are cut into a proper size, on the coated area so the epoxy resin/  hardener mix permeates the glass cloth.

Remaining broken part Bond

Hull

3. Apply Apply the epoxy epoxy resin/ha resin/harden rdener er mix mix to the contact area of a new part with the glass cloth, place the part on the glass cloth, then press it against the glass cloth.

New part

Sanding

Glass cloth

TIP: To bond the new part to the glass cloth firmly, roughen both the contact and the overlay surfaces with #40–#80 grit sandpaper, and

Hull

wipe surfaces clean with IPA. 4. Permeat Permeate e two glass cloths, cloths, which which are are cut to a proper size, with the epoxy resin/  hardener mix, and overlay the new part with each glass cloth, as shown. Apply chopped strand on corners to increase adhesion strength of the glass cloth.

Glass cloth

Chopped Strand

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Glass cloth

Chopped Strand

 

Hole in double-hull (reinforced hull) If it is difficult to repair from inside the hull, use filling material to fill the hole and then cover the hole in outer hull.

Filling material Glass cloth

Glass cloth

 

Inside hull

Outer hull Glass cloth

Breakage of strake Use chopped strand or glass cloth in cases where it is difficult to form a shape using lamination forming method.

3 4 Glass cloth

Chopped strand

5 6 7

Maintenance after repair Occasionally check the repaired area to be sure it is adhering properly. If any crack or separation is found, stop using the water vehicle and perform the repair.

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RTM/HLF Repair Materials and tools required Degrease/Clean Resin Fiber materials Defoaming To Tool Fi Fina nall Fin Finis ishi hing ng

IPA or or ac acetone Polyester resin Mat, roving cloth Defoaming ro roller Pai aint nt/g /gel elco coat at spra sprayi ying ng,, san sandd-pa pape peri ring ng and and com compo poun und d pol polis ishi hing ng

MATERIALS: Mat (Chopped Strand Mat) The mat is made up of chopped fiberglass strands approximately 50 mm (2 in) long which are spread evenly to form a sheet. It is categorized by weight (g) per 1 square meter which is indicated as a part of the product number. EM450 or EM600 is commonly used.

Roving cloth Roving cloth consists of continuous glass strand bundled together and combined to form a woven fabric. It is designated in weight per square meter. #320 or #580 is commonly used.

Polyester resin This is the resin normally used in HLF/RTM repairs. Before using a polyester resin, add hardener and mix them well.

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Hardeners Polyester resins and gelcoats are cured by the addition of hardeners. Resins are normally cured 1% by weight and gelcoats are cured 2% by weight. A volume of 5 cc of hardener per pint of resin will equal 1%. Therefore,, 10 cc per pint will equal 2% for the Therefore gelcoats. This quantity may be altered slightly, however, excessive amounts may cause discoloration, deformation, air bubbles, bubbles, and brittleness. On the other hand, too little will cause under cure.

 

The type of hardener to be used depends on the type of the resin/gelcoat. Make sure to use the correct type of hardener for the resin/  gelcoat and refer to the product specification sheet for the correct mixing ratio. Resin (cc) 100 200 300 400 500

Hardeners (cc) 1 2 3 4 5

Gelcoat (cc) 100 200 300 400 500

3

Hardeners (cc) 2 4 6 8 10

4 5

IPA (isopropyl alcohol) or acetone IPA or acetone may be used to remove oil and stains, clean tools, and in general clean up. This is also used to degrease RTM/HLF before applying laminations. Excessive use of acetone on surfaces may remove or deteriorate the gloss and texture.

6 7

Paste Paste is a formulation of polyester resin containing fillers such as glass powder or asbestos. This paste is used to fill small gaps or bond reinforcement reinforce ment materials.

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Primer The primer is a base paint formulated for better adhesion of paint to RTM/HLF.

Tools: The following tools are required. • Scis Scisso sors rs For cutting glass materials • Tapes and paper paper for for masking • Blade of of utility utility knife knife For trimming glass prior to full cure

• Pure bristle brush, spatula, squeegee, and small grooved mat roller For impregnation of glass materials, mixing/applying resins, and removing air bubbles

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• Grindi Grinding ng tools tools May include electric drill with grinding discs or rotary files, disc sander, files, sanding blocks, etc. • Spray Spray gun For applying gelcoat

 

• Electric Electric polisher polisher For finish buffing

3 4 5

• Sandpaper Sandpaper and sandin sanding g discs #40–#120 grit • Waterproo Waterprooff sandpaper sandpaper #400–#1200 grit For finish sanding

6 7

• Graduated measuring measuring cups and buckets buckets For measuring resin and gelcoat • Contai Container ners s For mixing of resin and washing of tools. Using a disposable container is recommended. • Weighing Weighing instru instrument ment Measuring of mat and roving cloth • Graduated Graduated cylinder cylinder Measuring of hardener • Dr Drop oppe perr Measuring of hardener

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• Dust protective protective goggles, coverall

mask, mask,

gloves, gloves,

safety safety

RTM/HLF material life Hardeners, polyester resins, and gelcoats will deteriorate after extended periods of storage and will, therefore, not cure properly. Typical shelf life is as follows: Material Polyester resin, gelcoat

Life 3 to 6 months

Hardeners 1 year Conditions of storage These values apply to temperatures of 25 °C (70 °F) or lower and in a cool, dr y area, not in direct sunlight. Keep all containers clean and tightly closed when not in use.

Repair chemicals can be flammable. Follow manufacturer's instructions for proper storage. Do not store in vicinity of fire or open flames.

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Types of damage Types of RTM/HLF damage are shown below. Repair procedures will vary accordingly. accordingly.

 

Examples of damage: Scratches on painted surface Gelcoat

RTM/HLF

3 Scratches reaching RTM/HLF Gelcoat

4

RTM/HLF

5 Damage (hole) to the RTM/HLF

Gelcoat

RTM/HLF

6 7 8 9

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Scratches on painted surface Procedure: 1. Wet s san and ding ing Begin by sanding area with #400–#600 grit waterproof sandpaper on a block until scratches are gone. Once scratches have disappeared, use #1200–#1500 grit waterproof sandpaper with lots of water. For best results, final sanding should always be in the same directions (e.g. back and forth). The surface should now have no scratches and have a dull shine. 2.

Polis olishi hing ng Clean the gelcoat surface with water and neutral detergent. Polish with a fine rubbing compound. If no polisher is available, polish with a rag and compound.

3. Appl Applyi ying ng mar marin ine e wax wax After polishing, apply several coats of a good marine wax, allowing each coat to dry prior to buffing and applying the next coat. Repeat this step.

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Scratches reaching RTM/HLF Repair area:

 

3

Procedure: 1. Clean scratch scratch out as much much as possib possible le using a small grinder, or sandpaper. The recess should resemble a shallow “U” or “V” when done.

4

2. Mask Mask the the surrou surroundi nding ng areas areas of of the scratch to minimize mess and work. 3. Mix desired desired quanti quantity ty of gelcoat gelcoat and hardener and spread into scratch.

5

4. Cover Cover scratc scratch h with a piece piece of plastic plastic film film using a flat end instrument to squeegee the gelcoat down flush with top of tape. Do not remove the film until gelcoat has dried. Once the gelcoat has cured,

6

remove the film and, using a small flat block, sand the area with #400–#600 grit waterproof sandpaper until level. 5. Finish Finish and and polish polish as in in scratc scratches hes on painted surfaces.

Plastic film Tape

6. For areas with numerous numerous scratche scratches, s, itit may be easier to sand the scratches out. Use a small fine-tip brush to apply the gelcoat, then coat the surface with PVA. When the gelcoat has fully cured, wash off the PVA, then block sand and finish as described above.

Tape

7 8

Gelcoat

9

TIP: The PVA may be sprayed on immediately after application of gelcoat or brushed on once the gelcoat has started to gel.

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Damage (hole) to the hull Repair area:

Procedure: 1. Marking Mark the area of sanding (scarfing) with tape or marking pen. The width of scarf (from the edge of the broken area to the edge of scarfing) should be 16 times larger than the hull material thickness.

Scarfing The width of scarf should be 16 times larger than the hull material thickness.

TIP: Scarfing means making a scarf along the edge of the broken area to widen the adhesive area. The larger the adhesive area, the greater the adhesive strength. Thickness of hull Width

Scarfing on one side Scarf only one side of the repair area if the material thickness thickness is 10 mm (0.4 in) or less, lightly loaded, or has a loading on only one side. The width of scarf should be 16 times larger than the hull material thickness.

of scarfing

 

Width

of scarfing

Width

Roving cloth and mat Direction of load

Reinforcing back plate

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of scarfing Thickness of hull

 

2. Sand Sandin ing g (Sca (Scarf rfin ing) g) Make a scarf. While sanding the surface, thoroughly smooth out the broken area at the same time. Make sure all delaminated material has been removed. After scarfing, clean the sanded area with a rag or brush. Wipe clean the repair surface.

 

3. Cutt Cuttin ing g fiber fibergl glas ass s Cut fiberglass (mat and roving cloth) in a proper size for lamination. Before cutting, verify the construction of lamination.

3

Construction of lamination As shown, laminate a mat, a roving cloth, a mat, and a roving cloth, in that order. The mat which is first placed should be 15 mm (0.6 in) larger at one side than the mat to be placed next. On the other hand, the roving cloth should should be 8 mm (0.3 in) smaller than the mat on which it is placed.

mm (in)

4

Mat Roving cloth

5 15 15 15 15 (0.6) (0.6) (0.6) (0.6) Hole

8

8

(0.3)

(0.3)

8

6

(0.3)

Mat

Therefore, the first-laid mat should be 30 mm (1.2 in) larger larger in diameter than the the hole, the next roving cloth should be 16 mm (0.6 (0.6 in) smaller smaller in diameter diameter than than the first mat. The second mat should be 30 mm (1.2 in) larger in diameter than the first mat, and the roving cloth laid on the second mat should be smaller than the second mat. Likewise, cut the mats and roving cloths to be laid subsequently, and laminate them. Finish the top of the lamination with two mats so the surface of lamination is slightly higher than the surface of the hull to be repaired.

Roving cloth Hole 1

Hole Diameter + 30 mm (1.2 in)

1

2

2

16 mm (0.63 in) smaller than the first mat

3

3

Finish laminate

7 8 9

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4. Prepar Preparati ation on of polye polyest ster er resin resin Weigh fiberglass and determine the required amount of polyester resin. Amount of polyester resin= Weight of total fiberglass (mat and roving cloth)  2 Weight of total fiberglass (g) 50 100 150 200

Amount of polyester resin (cc) 100 200 300 600

This mixing ratio gives the most suitable strength of RTM/HLF without waste of the polyester resin. Reference: The strength of RTM/HLF depends on the ratio of fiberglass. For repairs, it is advisable to make a lamination with at least 33% fiberglass.

40

30

Strength (kg/mm 2)

20

10

0

40

50

60

Content of fiberglass (Wt.%)

Tensil strength Bending strength Compression on strength

5. Addi Additi tion on of har harde dene ners rs In general, hardener is added at a rate of 1% to polyester resin, but this mixing ratio may vary depending on the manufactures. Add the specified amount of hardener to the weighed polyester resin according to the hardener addition chart on the product. Thoroughly stir the mixture.

Polyester resin (cc) 100 200 300 400 500

Hardener

1

Polyester resin

Hardeners (cc) 1 2 3 4 5

35

100

 

6.

Lamin aminat atio ion n Wipe down the sanded surface and coat it with the polyester resin/hardener mix. As shown in the lamination construction diagram, start the lamination of mats and roving cloths by placing a mat first. Lay the mat correctly, let it adhere thoroughly, then permeate it with the polyester resin/  hardener mix using a brush.

 

Notes on construction of lamination a. Apply the the polyester polyester resin/hardener resin/hardener mix to the mat layer, as roving cloth provides less adhesive strength. b. Mat should be applied as first layer, layer, then followed by a layer of roving cloth. Laminates may generally all be done at the same time providing greater compactness and strength in the repair. c. Roving cloth cloth layer layer should always be slightly smaller than the mat layer, and roving cloth should not be applied over roving cloth. d. A mat layer layer should be used as the last layer to aid in sanding and reduction of any surface pattern transfer.

3 4 5

7. Remo Removi ving ng bubb bubble les s Using a grooved mat roller, remove air bubbles from the mat carefully.

6

Any remaining air will cause layer separation. Next, place a roving cloth on the mat and remove any bubbles. Do not allow polyester resin/hardener mix to dry between lamination layers.

7 8

8. Comple Completio tion n of of lami laminat nation ion By repeating the above procedure, laminate the specified number of mats and roving cloths. The mat on top must be higher than the surface of the hull to be repaired.

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9. Surf Surfac ace e trea treatm tmen entt When the lamination has dried completely, smooth out the surface with a sander.

10. Coat with paste paste All attempts should be made to level the surface with fiberglass materials.

TIP: Once smoothed out, the surface will have many tiny pin holes which will trap air when applying the gelcoat. A polyester based paste may be applied and then sanded smooth prior to gelcoat application to eliminate these holes. Avoid application of automotive body paste as these tend to shrink and/or crack. 11. Surface Surface finishin finishing g Sand finished patch area with #80 grit sandpaper and wipe down with a clean, dry rag.

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Coat with gelcoat 1. Spra Sprayi ying ng of of gelc gelcoa oatt a. Instrume Instruments nts and tools required required An air compressor, a spray gun, paper tape, sheets of newspaper, etc. are required. Air compressor adjustment: Drain any water from the air compressor (tank and air filter), and adjust the air pressure to 5–6 kgf/cm2. b. Chemical Chemical compounds compounds required required The following items are required to spray gelcoat: • 2% Paraffin Paraffin solution solution (surface (surface wax) To provide an air hardenability, add 3–4% of a 2% paraffin solution to gelcoat. • Styrene Styrene monomer monomer Use styrene monomer to adjust the viscosity of gelcoat suitability for spraying. Avoid adding more than 5%, or gelcoat surfaces will be given an adverse effect. Acetone may also be used if styrene is not available. In cases where more than one application of gelcoat may be required, it is best to add the surface wax solution only to the last layer applied. This eliminates the possibility of wax being trapped within the layers. In other instances, it may be desirable to apply a light coat of PVA following the last layer of gelcoat and eliminate the use of the surface wax completely. The particular circumstances will dictate which option is best. Reference: General laminating polyester resins and gelcoats will not harden completely when exposed to air. This allows for multiple lamination or applications without having to sand between coats.

 

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Finish or sanding resins and gelcoats contain the addition of paraffin wax which floats to the surface as the materials cure and seals the surface from the air. This results in a hard finish suitable for sanding and finishing. PVA over a general laminating resin or gelcoat will accomplish the same end result as the addition of paraffin wax without introducing additional chemicals to the materials. c. Mask Maskin ing g Wipe the surface clean. Mask the surrounding areas.

d. Spray Spraying ing Hold a spray gun at right angles to and 30 cm (11.8 in) off the surface to be sprayed. Spray gelcoat at a steady speed. (Avoid spraying outdoors, if windy.) Reference: As a simple method, gelcoat can be applied with a brush. e. Full Full hardeni hardening ng Do not move the part which is being repaired until the gelcoat dries completely. It is advisable to use an infrared lamp in winter. H Hold old it 50 cm off the gelcoat surface and heat the surface evenly evenl y.

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2.

Wet s san and ding ing After the gelcoat has dried completely, the surface will have a slight “orange peel” appearance. Remove this by wet sanding with a #400–#600 grit waterproof sandpaper on a block then finish with a #1200–#1500 grit waterproof sandpaper with lots of water. As mentioned previously, it is suggested that the final sanding be in one direction only (e.g. back and forth) to aid in final buffing and gloss.

 

3. Finish Finishing ing with with comp compoun ound d Coat the gelcoat surface with rubbing compound, and polish it with a polisher to finish the surface.

3 4 5

Maintenance after repair Occasionally check the surface to be sure the repair area is adhering properly. If any crack or separation is found, stop using the water vehicle and perform the repair.

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Chipping or web-like cracks in the gelcoat In addition to scratches and breaks, RTM/  HLF may have chipping or web-like cracks in the gelcoat. The repair procedure differs depending on whether or not scratches or cracks are made through the gelcoat layer to the layer of RTM/  HLF.. While sanding, it can be determined. HLF For repairs, proceed as shown below: Repairs of chipped gelcoat or

web-like

cracks

Scratches are deep do wn to the RTM/HLF layer. Scratches do not reach the RTM/HLF layer.

Repair of a small break: 1. Scarfing (Sanding) 2. Laminate fiberglass. 3. Smooth out the surface of lamination.   (Coat with water-resistant paste.) 4. Coat with gelcoat. 5. Wet sand the gelcoat surface. 6. Finish the surface.

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Maintenance of FRP Routine care is important for FRP as it helps in maintaining the high luster. During maintenance, any damage to the FRP can be detected early so repairs can be easily accomplished ensuring long service life.

 

1. Main Mainte tena nanc nce e of lust luster er When it has faded or has lost its luster, the original luster can be restored by polishing to remove the oxidized layer. Polishing procedures: a. Clean the painted surface surface with water and neutral detergent. b. Polish with a fine fine rubbing compound. If no polisher is available, available, polish with a rag and compound. c. After polishing, polishing, apply several several coats of a good marine wax, allowing each coat to dry prior to buffing and applying the next coat. Repeat this step.

3 4

2. Fadin Fading g and and disc discolo olorat ration ion How to clean: a. Fading may may require the use of a heavy duty rubbing compound and subsequent polishing to restore the original painted surface luster. If this does not work, see item “d” below. b. Discoloration due to oil stains, stains, fuel stains, or environmental factors may be removed with detergents or industrial solvents if needed. A rag or sponge moistened with acetone may also help. However, avoid excessive exposure of painted surfaces to acetone as the surface may become permanently damaged. c. Marine Marine growth growth can be scraped scraped off off using sharpened wooden sticks. Avoid metal putty knives, etc. They will tend to scratch the painted surfaces.

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d. If all else fails, fails, use a waterproo waterprooff sandpaper to sand the painted surface so that it has a consistent color. Use extreme care as too much sanding will remove all the paintings and new paint will have to be applied. Start with #600 grit and end with #1200–#1500 grit with lots of water. For best results, final sanding should always be in the same directions (e.g. back and forth). Follow with polishing procedures given above. e. If none of the above above helps, it is time to apply new coat of urethane paint/  gelcoat.

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Evaluation of adhesive strength The adhesive strength of the repair depends on the type of resin and fiber material that are used. The results of the bending strength tests performed on NanoXcel using 3 different types of adhesive processes are listed below. These test results show that performing repairs using WEST SYSTEM epoxy resin and glass fabrics is recommended. However, even when a proper type of epoxy resin is used, if mat or roving cloth is used for the fiber material, the adhesive strength will decrease. The adhesive strength will also decrease if the resin or the fiber material is used in an improper way.

Roving cloth and mat are not used for repairs using epoxy resin. The don’t bindercontain that holds the mat together is dissolved by the styrene in polyester resins. Epoxies styrene as a diluent. Additionally, Additionally, if lamination was performed using roving cloth, the space between each layer is filed with epoxy resin, causing interface delamination and separation of roving cloth.

 

3

Bending strength a New Repair Manual (Recommended) • Epoxy Epoxy resin resin (WEST SYSTEM) • Glass Glass cloth cloth

b Previous Repair Manual • Epoxy Epoxy resin resin (Commercial product) • Mat Mat clot cloth h • Rovin Roving g cloth cloth

 

c Improper use • Polyes Polyester ter resin • Mat Mat clot cloth h • Roving Roving clot cloth h

4 5

a NanoXcel

6

material strength

b

c Bending strength

7 8 9

Stroke

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Dec. 2014 ABE (E)