white areas in fiberglass that is done

[bigbad4cyl]

I paid a helper to help me lay / wet my fiberglass...I stood out side and did the advice/ cut and mix parts...we stapled the cut sheets roving/ mat/ roving to the stringers and cross braces.... then I mixed up batches and handed them to him, and he used chip brushes/squeeges and wet out the cloth with me saying make sure you get that white spot over and over...well when we were done and it dried a day it looks ok, except for some white spots, some as big as 8 inches by 6 inches.... We wet out all three layers at once onto already wet out/sanded / acetone cleaned stringers.... there are only a couple of white areas on the horizontal parts............................................................. I have some west system syringes and am thinking the correct course of action is to drill a small hole in the white spot and fill with a syringe and epoxy ...is this correct any other advice...

 

[CalicoKid]

Re: white areas in fiberglass that is done

If the white spots are big bubbles under the glass you might be better off cutting the glass out with a knife and laying in a patch. Are they like big bubbles or is there decent adhesion to the stringer and hull?

 

[ondarvr]

Re: white areas in fiberglass that is done

The white areas can be water on the glass, resin turns a cloudy white when it's mixed with water. It can also be air, sometimes when the wood is heated by the resin curing, the air in it expands and forms large bubbles. Also knots in the wood can have oils in them that may cause an incomplete cure, leaving soft spots that may change color when exposed to high humidity.

 

[epresutti]

Re: white areas in fiberglass that is done

BigBad,<br /><br />Like Calico said, you need to figure out if the spots are delaminated glass. During my rebuild anytime I saw a cured bubble that I felt would comprimise the structure, I cut it out and re-glassed. Otherwise I drilled a hole and filled with epoxy (I used epoxy for my entire rebuild).<br /><br />What I discovered was that it was easier and faster to re-glass than trying to fill the void. I used my angle grinder to remove the "bad spot".<br /><br />Peace.<br /><br />Ed.

 

[reka12]

Re: white areas in fiberglass that is done

One trick that helped me a whole lot with glassing difficult wood corners and curves was to let the boat sit in the sun for the morning or afternoon and then bringing it inside and lay the glass. I found that the wood did not off-gas as it cooled and it really eliminated the bubbles. Laying the glass over 90's is hard as is any sharp angle. I also rounded all the 90 degree angles using a 1/4" router bit. The glass layed a lot better. Mike

 

[trackersocha]

Re: white areas in fiberglass that is done

all the above plus fillets in the inside corners, <br /><br />you probably have delaminated glass, cut it out and lay it again

 

[bigbad4cyl]

Re: white areas in fiberglass that is done

ive got a heat gun also , first chance i get i think im going to cut/ grind out the area and redue it corectly....no biggie i guess...

 

[trackersocha]

Re: white areas in fiberglass that is done

yea, not a big deal