Can I say the "F" word in here?

[Mike H.]

OK, I know I'm going out on a limb here, but my sister asked me this question about her Fiberglass boat:
"Sue, can you send me some web address for a boat repair forum? I found a small crack in the hull of my boat (when we finally got the last bolt cut off and turned the hull over). I need to patch it but have never used fiberglass before. The boat repair book I bought deals mainly with large holes like when a boat hits something large. It mentioned using epoxy on smaller damage but didn't give much info. Usually at the boat store, they are just sales people, not sailors or boaters and don't have any useful info to help. I want to get if fixed quickly."
I know this is a Wooden Boat forum, but can anyone give any suggestions? This is a catamaran she's talking about.
Thanks, and don't blast me too hard! :eek:

[ 06-18-2002, 09:51 AM: Message edited by: SueH ]

[NormMessinger]

Ignorant rush in where wise one fear to speak... So to speak. So. If it were mine I'd apply what I know about fibreglassing learned from building an airplane from googe, glass and foam. Repairs can be as strong as the original structure. Sand back from the edges of the wound one inch for every layer of glass. Lay on new plies to match each successive layer plus one more over all. Fair and finish.

Ah, but the trouble is, boats are made from glass matt and stinky stuff. Still scarfing in a piece aughta work the same, eh?

--Norm

[Buddy Sharpton]

Why did it crack? Dropped on something that punctured? Did the hull get bent so far that it could flex no more and cracked at the stress lines of a fold? Is hull a single layer of glass or a sandwich cored with foam or wood? Can you get to the inside easily? Get down to that boat store and invest $3 in Gougeon's WEST repair book for fiberglass boats, not the one for wooden boats. You'll see why the questions and what is involved all in one trip. Great resource and yes, you can fix it without buying in for a bunch of special tools and hassles.

[Mike H.]

Thanks for the help, guys! I've passed it along to my sister.
Buddy, oddly enough my sister is a graphic designer in Atlanta, too! You might be cubicle mates!
Norm, you built an airplane? cool!

[L-M Ramirez]

Okay, here comes the catter. It is an old 1975 MacGregor Venture 15' cat that I bought after college and still have and sail. I have never used fiberglas before and would like some tips from someone who has. The crack is not bad, about 4 inches long and not open, but you can sure see why the hull has been taking on water. The hull is closed, only about a quarter inch or so thick and nothing laminated inside. All the repair will have to be done on the surface. The boat is older than some of our kids so we are kind of attached to it. Thanks and sorry it isn't wooden.

[Scott Rosen]

I'd take the lines and measurements off the existing hulls. Then I'd rebuild it in cold-molded wood. It'll outlast you and your kids.

[Bruce Hooke]

Since you can only work from the outside it will be a bit of work because you will need to blend your patch into the surrounding area to get it to look good, but it can definitely be done and it's not that hard. Buddy's recommendation on the Gougeon book is probably a good one, assuming it's written as well as their book on wood & epoxy boatbuilding, which I expect it is. If you can't find it locally you can order it direct from Gougeon http://www.westsystem.com

Basically what you are going to need to do is grind down the fiberglass along the crack so that you have a very broad V that ends in a feather edge at the crack (i.e. go almost all the way through at the crack. Then you will need to fill in the V with some epoxy and 'glass cloth. The final layer of epoxy can be tinted with colorants to try to match the hull (this will be a challange even if the hull is white because it has probably gone a bit gray over the years). Then comes the 'fun' of sanding it smooth and polishing it to match the rest of the hull.

That, however, is just a quick overview. There are a fair number of little tricks that will help you along, but if you already have some books you may be able to fill in the details, or you can get the Gougeon book and look for the details there.

As you can see, if there is any way to get at the inside of the hull that would make things a good bit easier...

[Memphis Mike]

Welcome L.M. Check your email and stay the
H#%$ outa Misc. :eek:

This is one I been tryin to convert guys.
My apologies. ;)

[Mike H.]

Welcome in L! That "Stay the H*&%$# outta Misc." sounds like a dare to me! smile.gif

[Todd Bradshaw]

This may be off-base in this case, but before I started grinding into the hull and buying books and epoxy, I'd run the boat past somebody who knows something about fiberglass boats and make sure it really is a crack in the hull, not just a crack in the gel-coat. You haven't said much about the actual nature of the offending orifice. Can you see through it or see white fuzzy stuff hanging out? Does it leak? Is the hull soft around it - or perhaps more flexible on one side of the crack than the other? Does water come out when you push on it? Sounds like a job for a combination fiberglasser/proctologist, but it could, in some cases, be a pretty easy fix.

[L-M Ramirez]

It is definitly a crack in the fiberglas, not just the gel coat. It is not bad, but the hull has leaked and we could never figure out why until we took the whole thing apart and turned the two hulls upside down to check out repainting. It is about four inches long, it is not a puncure but looks like the boat maybe hit a rock heading into shore sometime in the past. It is a slow leak but the one side of the catamaran sinks down into the water after a few hours out. It is pretty stiff and rigid and I had to check it out pretty thoroughly to be sure it was a crack all the way through. Would like to fix it myself if possible and as soon as possible.

[Tar Devil]

Norm, you built an airplane? cool! No, Sue. Norm built a cool airplane . He flies it backwards all the time (not kidding!!). And when he's not flying, it kneels to him in humble servitude.

BTW, if memory serves me the same guy that designed Norm's plane also built the wing/sail thingy that powered Dennis Conner's 1988 Stars and Stripes catamaran to victory over that big white monster the Kiwis brought to California.

Later,

Phil

[NormMessinger]

I don't what to hijack your thread L-M. Blame Sue, she asked... smile.gif

http://www.imagestation.com/picture/sraid23/p94198ff7450529b3d462b5c6dca0e4a4/fda24c84.jpg

Right, designed by the same guy, Burt Rutan, as designed and built OConner's wing/sail. Remember the Voyagure that flew around the world non-stop with out refueling? Same designer.

N24PN will carry Phyllis and me along at about 145 knots sipping 5.5, okay, say 6 gallons per hour from a 50 gallon tank. I've never filled the tanks since my bladder isn't up to it.

Nice thing about fibreglass construction, done right, is any shape is possible, the surface is slick as polished glass, cracks don't run, life expectancy is unlimited, etc. That's in airplanes. Doesn't seem to work that way for boats but it could. Except boats should be wood, mostly.

--Norm

P.S. And it doesn't fly backwards. It just happens to have the engine in the back where Orville and Wilber intended an aeroplane should have it. tongue.gif

[ 06-18-2002, 03:00 PM: Message edited by: NormMessinger ]

[Tar Devil]

And it doesn't fly backwards. It just happens to have the engine in the back where Orville and Wilber intended an aeroplane should have it Yeah, and Orville and Wilber had the tail in front and wing in back... Just like your's, Norm.

Later,
Phil

[Buddy Sharpton]

Definetly a crack? So you need to grind away a beveled tapered edge about eight times the width of the hull . If that's 1/4 inch-seems thick for a cat to me- then about 2 inches wide all around. Open up the width of the crack about 1/4" wide to. You're going to take a piece of cardboard a little bigger than the ground of area- put a string right thru the middle. Slather on many layers of epoxy and glass on top of that cardboard- slide it thru the hole and snug it up against 6he inside of the hole with that string and let it get firm but not fully cured. Then cut the string and lay on enough layers of glass and resin to fill the 1/4' depression that the outside of the hole has become. Let it all kick, grind fair and smooth with some filler and repaint or re gel. In a nutshell, that's it. Materials and a disc sanding wheel for your drill.

[Todd Bradshaw]

That's the ticket in a well spoken nutshell. If you can get something inside the hole to rough-up the interior surface for bonding, all the better and make sure that it's dry in there before you add the patch.

[Jim H]

I was told (by the manufacturer) that gelcoat may not adhere well to epoxy. Many of the older hulls were made with polyester resin and then gelcoated. If you talk to a local repair shop they can probably confirm this for you. If so, use polyester resin to make the repair. Matching gelcoat colors probably doesn't matter to you if it's below the water line and painted, but if you do want to it's possible. The best way to match light colors is to use the white gelcoat instead of a color base (tinting base - used for darker colors). I bought a quart of white gelcoat, divided in half and sparingly mixed in some yellow & brown (for an off white hull). If it gets too dark you can just mix in some more white from the other can. To test just dab some on the original gelcoat and let it dry some.

Jim

[Figment]

oh, wait..... (rereading more carefully) this is a beach cat? no problem. I've done this a dozen times (no, not the same hole re-repaired over and over again).

as everyone above has said... hacksaw, grind, file, sand, do whatever you need to do to get back to good solid glass, and then feather the hole out nice and wide. try to at least rough up the immediate area around the crack on the inside of the hull if you can. then turn the boat back over so it's right side up. trust me. support the boat so that the hole is the lowest part of the hull. gravity is your friend.

get yourself some fiberglass cloth, polyester resin (it's what the boat is made of. not epoxy), a resin syringe, some wax paper, and some masking tape. when I refer to "resin" below, I of course mean resin-properly-catalyzed-with-hardener.

put on latex gloves. cut 4 pieces of glass cloth in sucessively smaller sizes to approximate the taper you've made around the hole.

cut some of your scrap fiberglass cloth into a zillion pieces until you've got a big pile of "cat hair" with the fibers being 1/2" to 1" long. cut another piece of wax paper about a foot square, and lay it over your left hand, and pour a little bit of resin into the palm of that hand. now with your other hand add more and more of the cat hair until you've got a good handful of hairy resin. set this aside for now.

cut a piece of wax paper that's a couple of inches bigger than your hole and run masking tape around all four sides. lay the paper down on a bench or something so that the tape is sticky-side up. put the biggest piece of cloth you've just cut on the waxpaper, and wet it out with the resin. then the next smaller, and resin, and so on... this is your patch.

now go over to the boat and arrange things so that both of these pieces of wax paper and a couple of resin-filled syringes are within easy reach.

First take the hairy-resin and stuff it all up into the crack, and use a popsicle stick or something to see that it gets spread around inside as best you can. don't worry about the resin that's now dribbling out of the hole.
Next take the piece of waxpaper with the patch, and fit it up to the hole, pressing the tape to the hull along two adjacent sides.
now sneak the syringe up between the patch and the hull and inject some resin up into the cat-hair part of the repair, and then squirt the rest of it onto what you can see of the patch.

Try to get the wax paper nice and smooth against the good part of the hull and press down the final two sides of the tape. tap, rub, caress, do whatever you need to do to chase any big air bubbles to the edge. spend some time on this, as the surface you see before you will be exactly what you have to deal with after everything cures.

After 12 hours, the wax paper should come off easily and leave you with a perfectly smooth repair that only needs a little bit of sanding prior to paint or gelcoat.

This technique is golden for two reasons: 1) keeping the boat right-side up eliminates the need for some kind of backup-material inside the hull to keep the resin from just disappearing into the crevasse. 2) the wax paper allows the resin to cure in a no-air condition without any need of PVA or other mold-release coating.

Hardcore beachcat people will turn their nose up at this because the repair is about 4x as heavy as it needs to be, but if you've been sailing around with a hole in the hull you're obviously not out there to win many races.

long post. nothing to do with wooden boats. go sail fast anyway.

[formerlyknownasprince]

Hey Norm - you don't fill the tank because your bladder won't last - why do you think God invented PET bottles? Just be sure never to buy yellow drinks - never know when you'll mix up the new and the recycled.

Ian

[Donn]

Norm...Sporty's carries these neat little gadgets to help deal with IBB. They even carry a SWMBO adapter:

Little John and Lady J

http://www.sportys.com/terryc/images/6462m.jpg

http://www.sportys.com/acb/webpage.cfm?&DID=19&WebPage_ID=68

[Memphis Mike]

Don't go to that expense Norm. Someone I
know that used to drive long distances
took a piece of garden hose and a funnel
and drilled a hole in the bottom of his
jeep and wallaaaa! He did seal everything
with duck tape I might add.

[Tar Devil]

Don't go to that expense Norm. Someone I
know that used to drive long distances
took a piece of garden hose and a funnel
and drilled a hole in the bottom of his
jeep and wallaaaa! He did seal everything
with duck tape I might add.
I think Peter Garrison had a similar rig in his ocean-hopping Melmoth homebuilt airplane.

[JimD]

I like what sailortect says, not that I've ever done it, but the part about using polyester resin, not epoxy. I've heard the two don't do too well together, bad idea to repair a polyester hull with epoxy. (just what I read somewhere)

[Todd Bradshaw]

Supposedly, epoxy will bond better to cured polyester than more polyester - but well done polyester patches seldom fail. I don't generally like fairing epoxy on polyester as the two seem to have different sanding rates and heat tolerance, at least for the first few days. Polyester shrinks as it cures and some times this can be an annoyance that you can get around by using epoxy instead. For this boat, polyester should work just fine.

[Mike H.]

Wow! I told my sister she'd get a lot of help in here, and you guys have been great! Now she not only knows how to fix her boat, but the bonus info about how to pee while piloting a plane! :eek: At no extra charge!
Cool plane, Norm! very unique looking design.
Thanks again, guys.

[NormMessinger]

Funniest story I ever heard related to flying Long-EZ's was told by the mayor of Bean Town, a 75 year old pilot who had equipped his EZ with a relief tube. That's a tube with a funnel on one end running down the landing gear and out the back end of a wheel pant. Seems he was flying one day when outside temp was below freezing. When the funnel filled up he was stuck flying with one hand and holding the funnel with the other, no easy task. I wouldn't do his story justice if I tried to tell it but everything came out alright in the end. I sure wish I had a recording of him telling the story.

--Norm

[Memphis Mike]

Norm, maybe we could rig it with a
heater coil. That would keep it from
plugging up in the cold. :D

[On Vacation]

Posted by Norm.
"Nice thing about fibreglass construction, done right, is any shape is possible, the surface is slick as polished glass, cracks don't run, life expectancy is unlimited, etc. That's in airplanes. Doesn't seem to work that way for boats but it could. Except boats should be wood, mostly.'

Someone in charge with national holidays, check in on information of making June 19, 2002 Messinger holiday in memory of the mental stability loss of our late great fleet commander. :D

[Tar Devil]

Ever wonder why it feels like it's raining from a cloudless sky? I'm gonna start looking up for Long EZ's then head for cover.

A somewhat similar experience... Back in my skydiving days, we were milling around the jump center one humid summer day, packing chutes, chatting, going over jump manifests when the owner, an ag pilot, came roaring over in his new Cessna AgWagon. He had just picked up the plane from the dealer, filled the tanks with water and proceeded to cool us off. :eek: Those of us on the ground, not knowing exactly what was being dumped from that ag plane, started grabbing water hoses and rinsing our clothes and hair. We were still bathing when he taxied up, LHAO.

Later,
Phil

[NormMessinger]

What's that? Boats shouldn't be wood, mostly? Hey! Every day's a holiday around here, if one applys varnishing jargon to mental states.

--Norm

[Buddy Sharpton]

I don't want you to get nervous on the epoxy vs. polyester resin choice. I have used both on polyester/ fiberglass composite boats. I feel the epoxy bonds better, but as has been said, lots more polyester "patches" out there and well sanded,well made, they hold just fine. Sometimes gelcoat doesn't work easily over epoxy, so you can always put on a final layer on 6 oz boat cloth with polyester resin over the epoxy repair befor you do the gelcoat. I think the "cat hair" technique is well described and probably a bit heavy, but so what. One or two pounds tops. Go with it.

[NormMessinger]

WEST and System Three sell chopped glass for those that are excited about making their own.

--Norm

[L-M Ramirez]

Thanks for all the good advice. One thing about doing a repair like this, you feel like you know your boat when you are finished. Some of the suggestions are for working from the inside of the hull but believe me, these two hulls are closed up tight and there is no way to get to the inside to work a repair. It will all have to be done from the outside. Anyway, I owe you one and thanks again! Priced marine paint this weekend and feel like Fred Sanford with those coming to join you Elizabeth heart attacks!!! Wow! Oh well, what you gonna do?

[Charlie J]

well- yeah - there IS a way to work from inside. There are many many old Hobie 14 and 16's out there with extra 4, 5 or 6 inch round screw in deck plates on top of the hulls just in front of the pylons. Cause when the pylon gets knocked loose, that's how you get inside to glass it back in place. You could use the same idea to get to the hull bottom.

[Andreas Jordahl Rhude]

www.fiberglassics.com (http://www.fiberglassics.com)

[Figment]

This thread really should be referencing www.catsailor.com (http://www.catsailor.com)
but anyway......

With sailing cats, installing an inspection port in the deck within 3' forward of the main crossbeam is certain death for that hull. That area of the hull us under a lot of stress while sailing, and that area of the deck is under INCREDIBLE stress during a pitchpole-capsize.

of course, this depends on how and where you sail. My observations have been that within a season or two the hull will develop cracks as a result of this weakening of the deck. if left unattended over time, I've seen hulls snap in two under heavy conditions.