Bottom of boat ,Bubble and cracks

i guess this was a bad post, no one has fixed a bottom of a boat from sitting in the water? Does anyone know of a good product to use to fill in my holes?

Bubbles in fiberglass that was immersed in salt water sounds like hull pox. It was quite common in older mono hulls.
I would do some Google searching for "hull pox", & related topics in monohull forums. There should be lots of advice.

~~ Their "BLISTERS". I had them on my mono, They are fixable, I didn't fix mine,,, sold the boat instead... Do they have a 'west marine' in PA ???....... I don't know much about fixin them besides sanding them down and letting them dry out then fill em in with 'goop' stuff from westmarine........ (I'am yer neighbor up north~~ NY)

sand them off with some 80 grit, blow the repair area off real good with air hose/tip @ 80 or so psi to get out all dust/particles, wipe down area with acetone and CLEAN rag, mix up west system with coloidal silica(peanut butter consistency), spread mix with plastic bondo spreader over repair areas, let dry, sand, do again to get any voids left, sand smooth, sail it this year. we have a strategy for old boats...fix only what you have to the first season, sail it, next year fix what it needs and then do some cosmetic stuff...the boat will tell you what it really needs this first season!

OK here is what i am working on http://youtu.be/v-tM48iWYaQ

Thanks all

That is a classic case of hull pox, also known as blisters, boat pox, or damage by osmosis. You may recall the classic high school biology experiment demonstrating how osmosis works. (Tie both ends of an osmotic membrane, toss it into a container of salt water, & wait. In a few days it will swell up nearly to bursting).
I've seen it on some boats I looked at in Vancouver in the '80s. I've never fixed it, it will be labor intensive to do properly. There is a ton of material on the web, just google it. You will want more info than you will get from a few posts. Good luck.
Here are a few hits, Don Casey has some very good books on hull/boat repair.
http://www.boatus.com/boattech/casey/03.htm
http://www.boatmexico.com/content.php?key=loftpost&lid=29&cid=&rid=&id=132&ex=0&content=
http://www.epoxyproducts.com/blister4u.html
http://www.zahnisers.com/blisters_hydrolysis.htm
http://boatsafe.com/nauticalknowhow/1220983tip.htm

Epoxy based filler or gelcoat if its made with polyester.
PPG 2 part paint to finish..
add anti fouling coat to taste

Ppg 2. What is that.. is that just regular paint??

PPG is a paint i used on sailplanes for years.
Its a 2 part automotive / plane paint with a 40yr lifespan
Gives a great finish and is very tough

So it is meant to be in water this paint? PPG is here in Pittsburgh if its the same thing? And you have used this on BOAT HULLS?

do you plan on the boat staying in the water ? if so then you will need to paint it or else it will blister again...did you read all those links ed refered you to? they were good, all you need to know, read them all... if you are not keeping the boat in the water then i would not paint the boat this year or at all(repair gelcoat)...these decesions will affect which products you use. hull painting is a HUGE undertaking and expensive...it really sucks when you do a paint job and then have to do more repairs the next season. i would do the least invasive fix this season and see what happens...are new spots popping up?...running the boat into the sea wall...finding soft spots/fractures in hulls...and so on. that's why we like to get a season on the water first before we do any cosmetic stuff, don't put the cart before the horse...if you do paint, then there are are some big decesions as for paints/primers and the like but i wouldn't rush into anything right now. just "PUDD" up the hulls, rig the boat, and see how she flies! you might be fixing some big ticket items you haven't thought about!

soulofasailor wrote: So it is meant to be in water this paint? PPG is here in Pittsburgh if its the same thing? And you have used this on BOAT HULLS?

Nope I have never bought a boat with Chicken butt...
Talk to your PPG sales guy he will give you the low down on the paint for marine applications.

On aircraft it works wonders and if I was to refinish my Stiletto 27 I would use that paint.

Cheers

tahoeprindle18 wrote: I have never bought a boat with Chicken butt

What?

DamonLinkous wrote: [quote=tahoeprindle18]I have never bought a boat with Chicken butt

What?

LOL

As in bumpy texture

Edited by tahoeprindle18 on Jan 02, 2012 - 03:50 PM.

tahoeprindle18 wrote: [quote=DamonLinkous][quote=tahoeprindle18]I have never bought a boat with Chicken butt

What?

LOL

As in bumpy texture

Oh, I see, here I was looking all over for a "chicken butt to US Dollars" converter.

Welcome back! Damon

What is a CHicken Butt?

What is a CHicken Butt?

bottom of your boat with osmosis bumps like chicken skin..

yes OK some of portions of the boat do have chicken BUTT then! hahahha i am just sanding that