Fiberglass Repair

 

On any fiberglass boat whether, it’s a ding, a scratch or a hole it needs to get addressed. Some of these repairs are better done by someone with experience whereas the minor ones are easily accomplished by a novice. Firstly, fiberglass is a general term for glass matt infused with a hardening chemical. This chemical referred to as a resin is either a liquid, a gel or a paste. The resin is commonly a two-part component and when mixed together in exact ratios under a window of atmospheric conditions the maximum strength is attained. The amount of catalyzed resin to fiber, whether it be glass, carbon or another form of fiber is also critical to achieve the best strength to weight ratio. Working with resins is deceiving because on the surface it all appears to be copacetic while internally it’s failed because the mixture got to hot and fractured within, or it has not quite hardened to it’s full potential and when baked by the sun it will fully cure and show through the filler or debond. Therefore, if large, structural and even highly cosmetic repairs are required consider soliciting experienced fiberglass repair help. For any repairs knowing what type of resin was used previously is important. Using one type of resin, say a polyester resin on a different type of resin such as a vinylester resin especially when it’s cured does not always work. It might appear that is bonds but in fact is it stuck to the surface and will delaminate with time. One of the issues with reinforced resins is that even cured resin is still undergoing a chemical change. Applying new resin to cured resin creates a situation of two mediums undergoing change at different rates and this can lead to issues down the road. There are resins available that are better suited to chemically bond to various substrates and substrates of different ages etc.

 

Fiber Glass

 

Fiber glass or glass fiber is available in different forms. The basic material is the same and that is it is made of glass. The glass is no different than glass found in a store front window or household wall insulation. Here the glass is in thin strands and is bound together with a binder to form a matt such as the chop strand matt. Longer strands are woven into cloths and cloths are combined to form a heavier roving. The type of fiber combination required is dependent on the strength required, the shape and the cosmetic characteristics required. Glass fiber is not the only choice available for fiber reinforced layup. Products such as carbon fiber or Kevlar fiber are also available. The latter are used where weight savings and higher strengths are required. Fiber reinforcing is sold by wight and not all cloth or roving is compatible for all resins.

 

Resin

 

Ester resins such as polyester and vinylester are fairly forgiving, easy to work with and are thus popular and provide good results. Epoxy resins are available in multiple formulations with some specifically produced for the marine environment. An ester resin or an epoxy resin that is constantly immersed in water especially saline water will eventually absorb water or salts therefore using resins formulated for the marine environment from manufactures such as ‘3M®’, ‘System 3®’, and ‘West Systems®’ is important. Using personal protective equipment is important especially working with epoxy resins. Fillers and Sealants

 

Once a fiber reinforced repair is done the repair should not be left unsealed. The glass fibers although encased in resin still create a pathway for moisture intrusion. Fiberglass Fillers, be it ester or epoxy based are available that are specially formulated for the marine environment such as the ester filler from ‘3M®’ or the epoxy based filler from ‘Pettit Paint®’. Repairs that do not receive a layer of gelcoat as a final sealer should get a barrier coat such as the epoxy barrier cote from ‘Interlux®’ applied to seal the repair in preparation for paint.

 

 

Fiberglass Tools

 

No fiberglassing repair work is not accompanied with grinding. Personal protection is a must, from a good fitting chemical face mask to gloves and clothing protection. The chemicals used are of the harshest and the glass fibers are microscopic and are quickly airborne. Fiberglass layup does require some specialized tools such as layup rollers that are used to expel entrapped air in the layup and help shape the fibers into the mold or repair.