will bare fiberglass absorb water

[Goose]

i had some issues with my surface on a part i made so i sanded it down to bare fiberglass.i sprayed it with epoxy primer and it turned out with pinholes everywhere which i expected.my question is will fiberglass with resin already cured in absorb water

 

[Kennay]

With polyester, that is how blisters will form (More or less.) That won't happen with epoxy, and I am not sure about vinyl.

Why don't you just spot fill the fish eyes?

 

[snowxr]

Gas can leach it's way through exposed fiberglass, so I think water has a chance to do the same.

 

[Motorheads5]

If you have silicone anywhere on the boat it will fisheye. I know some people use silicone spray as a corosion block I don't know if that's your problem or not. I have been told that fiberglass by itself will absorb moisture it need's to be sealed or gel coated.

 

[Goose]

it fisheyed because i sprayed over bare fiberglass im not worried about the looks im worried about the fiberglass breaking down due to the water being absorbed

 

[Motorheads5]

it fisheyed because i sprayed over bare fiberglass im not worried about the looks im worried about the fiberglass breaking down due to the water being absorbed

I wouldn't worry about it, the inside of most of the yamaha hull's are bare fiberglass.

 

[stanton]

my hulls got a bit of water in the bottom like all the time and its good.

 

[SUPERJET-113]

This doesnt really apply to your situation to much, but fiberglass strands are like little straws and when exposed to liquids, can absorb them slowly through capillary action.

 

[yamaslut]

it fisheyed because i sprayed over bare fiberglass im not worried about the looks im worried about the fiberglass breaking down due to the water being absorbed

are you sure??? fisheye usually means silicone/oil, water in the air lines or cleaning the surface w/ a reducer instead of using a pre-paint cleaner. not sanding the glass would cause it to not stick too...

 

[yamaslut]

I wouldn't worry about it, the inside of most of the yamaha hull's are bare fiberglass.

once you sand the fiberglass after it dries it will start absorbing water. if you don't sand it, it will be fine

 

[crammit442]

are you sure??? fisheye usually means silicone/oil, water in the air lines or cleaning the surface w/ a reducer instead of using a pre-paint cleaner. not sanding the glass would cause it to not stick too...

I think what he's referring to is a part straight from the mold that wasn't gelcoated. There are very small porosities that cause most coatings to fisheye. The epoxy primer he sprayed in mold didn't work well so he sanded and tried to apply an external coat. Sometimes the viscosity of the coating is low enough that it won't bridge the holes. This is always a challenge when I build visual carbon parts without an in mold gelcoat. I hope that makes sense.:Thinkingof_:

 

[WFO Speedracer]

It probably fisheyed because of trapped mold release (wax) in some porosity of the fiberglass part,that would be the logical explanation here.

 

[Goose]

it didnt fish eye its the pores in the fiberglass.when i pulled the part half the primer stayed in the mold and half was on thehull and wasnt fully cured i dont think that the primer sat long enough before i laid over it

 

[yamaslut]

I got ya....

 

[bimmerboy570]

It happens what can you do.