Newby needs to repair hull

[markd514]

It is finally getting warmer to start the repair. Quick question. I have the hole in the hull cut away, and tapered to at least 12 to 1 ratio. As stated before, all work will be done on the outside. I have read a few articles on this and nobody can seem to tell me the answer.

Do you start the FIRST layer of fiberglass cloth the entire size of the hole AND tapered fiberglass, then gradually reduce in diamater until you reach the built up thickness, or do you do it the other way around? Does it matter?

[jim lee]

I've been told that different people like to do it different ways. Some start small and work out to the larger bits, some start with the largest bit and work down to the smaller ones.

I like the small -> large camp. This way you can see how the different layers are matching up with the original and keep a bit of an eye on your progress.

Good luck, I don't envy you doing thins upside down!

-jim lee

[tunnels]

Originally Posted by markd514

It is finally getting warmer to start the repair. Quick question. I have the hole in the hull cut away, and tapered to at least 12 to 1 ratio. As stated before, all work will be done on the outside. I have read a few articles on this and nobody can seem to tell me the answer.

Do you start the FIRST layer of fiberglass cloth the entire size of the hole AND tapered fiberglass, then gradually reduce in diamater until you reach the built up thickness, or do you do it the other way around? Does it matter?

I always do a layer of csm ocer te whole job and then build up from there . The most important thing is to grind well back to get a big foot print to bond to . If the boat was poly id also go with Vinlyester resinfor th whole repair better adhesion to the old poly . I also use peel ply over th top to help compress the glass a little and you are able to see how much material you have and give a smooth finish to work with .
Good luck

[markd514]

thanks ...I am going to use epoxy resins and a strong knytexl cloth.....photos coming

[markd514]

Progress is slow due to the winter. Last fall, I used a sawzall to remove all bad,delaminated fiberglass. Then I ground it down to a 12 to 1 chamfer. I used some 1/2 inch styrofoam and glue to shape the hole. After it dries, I will clean it, sand, and apply one small layer of cloth to give a more durable shell to use as a starting point. I will then sand it all again to give me complete fiberglass to start the "real" layup process. BTW, the hole is about 30 inches long and goes up about 5 inches on each side on the widest part in the middle of hole. As I said before, I would love to also repair from inside as well, but that means cutting a huge access port in the fiberglass deck, which would be counterproductive, not to mention look like *#&^ when finished. It is molded and textured fiberglass. If it was just carpet, then it would be a no brainer. I am using epoxy and a biaxial cloth on the outside only.

[PAR]

It's coming along. Cut the coat hanger and fill the hole before you forget . . .

[markd514]

I did not start the layup yet. Hopefully this weekend. The guy at US composites told me to only do 3 layers at a time. I thought I could do all 9??? I mean, spaced an hour apart. WHo wants to sand down 3 times?

[tunnels]

Three layers at a time is about right . Polyester resin heats up when the layers are thick ok!!!
The heat when the resin gells causes distortion and shrinkage .
The more glass and resin the more heat ,the bigger the problem !!
At 9 layers in one hit and you have a bar -b -que boat !!
Listen to whats being said and heed the warnings . Need a couple or three hours between each lot of 3 layers of glass you lay .
The resin needs to do its thing and completely cool out like 100 % , you dont need to sand between layers .
Two hits in a day i would plan for!, one in the morning and one after lunch then the same next morning .

Whats the glass lay up you will be laying ? Chopped strand (what weight ) and a woven plus another chopped strand ?

[markd514]

I used all knytex biaxial glass. I just have to sand a do a final fill.