FIBERGLASS REPAIR.... Who knows it, who does it?

[IndyArms 10,186]

As the topic states... I need some fiobreglass repair advice.

 

 

I have a 26 foot Oday sailboat that a cleat got ripped off... Its now a jagged hole about 4 inches long by 1.5 inches wide... The thing is... I REALLY cant get UNDERNEATH where the hole is to really work on it... I could slip a board up in there and put some screws through the top into it to pull it up snug underneath and fiberglass over it... but is that what I want to do???

 

The cleat doesnt have to be put back in that exact spot... it can move back 6 inches, or a foot if need be... so the repair doesnt have to be structural and load bearing, as much as just rigid enough for where it is, and cosmetic.

 

If pics would help... I can easily take some... but I was hoping any body-shop guys out there would be able to say easily " Just do this... it's EASY!!! Blah blah blah... !!! "

 

I watched a bunch of you tube videos... I pretty much understand the basics of what I gotta do... I have done some fiberglass work once on the inside of a pickup truck bed to fill in some holes... it wasnt pretty but it worked... but I also didnt NEED it to be pretty... just to keep water from getting up inside the bed. LOL

 

I will buy whatever is recommended as far as bat/matt/cloth. I have a can of gelcoat already for the hull, so painting is not an issue. I also have a random-orbital sander and will buy the appropriate grades of sanding papers when I get to business.

 

What am I missing? anything I overlooked? I just want to make sure I have the proper technique for " from the top " work.... not from the underneath...

 

I am pretty much going to go with THIS:

http://adventure.howstuffworks.com/outdoor-activities/water-sports/how-to-maintain-a-boat1.htm

 

 

Thanks in advance!!!!

[cgculber 6]

I'd probably take an orbital sander to the hole first and make it nice and clean. Then I'd sand a generous area around the hole to accommodate a beefy patch (the bigger the patch, the stronger it will be in general). Then I would do pretty much exactly what you suggested: slip a board under, add screws to make it snug and then glass over the whole mess.

 

I think the most important part would be making the patch big enough; otherwise it will shear when any real stress is applied. You'll want to be as strong as possible.

 

AND, don't add too much styrene to the polyester resin (it will kick hot, form bubbles, and then be generally weaker). Don't add too much resin in general (excess resin means a weaker bond). Don't add too much kicker either; giver yourself enough time to make a clean patch. Keep an eye on it, work out the bubbles and take away excess resin (there should be no pooling on the fiberglass).

 

And don't use that UV cure resin either, that shit sucks. It's great for ding repairs but not something like this involving structural integrity.

 

And lastly, practice the glassing on something else first so you're confident of your styrene, resin, kicker mixing self first before working on the boat.

 

*Discalimer* I shape surfboards not boats, so there is a chance I'm full of shit.

 

I hope this helps and good luck! B.O.A.T. Break Out Another Thousand!

[RED333 1,025]

I have done a bit of that repair my self as well.

1st I will tell you MESURE you mix very carefully,

the stuff WILL catch fire if you get to much catlist in,

Saw a mold burn at a boat factory, mix was to hot.

I have set mix on fire my self, trying to work to fast.

 

Depending on how thick the deck is, bevel top and bottom adge of the hole.

If you can get a die grinder or drimel in there if would go easer.

I would use mediun wieght mat on the inside of the hole,

and fine mesh on top, use the board inside( at least a good hard wood 1" thick) and one outside, put

a piece of heavy plastic over the glass and under the top board

to keep it from sticking, use the boards as a clamp to hold things tight.

Use SS steel pins to keep from squezing to tight. if you are good at their placement

When you pull the pins they will be where you bolts will be for your cleat.

As far as gell coat, I was never any good at that, I could always see where my patch was.

 

So, was the cleat pulled out in a storm, or did you have the OL tied up for the nasty?

[obiwanbonjovi 337]

just make sure to feather the repair good, in other words, grind the hole outwards at an angle so the repair glas has a large area to stick to other than the hole.

use a block to sand it if you try to make it flat with the orbital sander you wont succede use cloth for the first coat and get as many layers as you can, then grind it a little and use a coat of matting for the top layer.

[brad cole 65]

did some fiberglass work on CH53 choppers in the core. best to do multiple layers, gradually increasing in size, sand entire area to be worked on, install backer, clean area with die grinder and make different depth ( valleys) if you will .cut fiberglass mat while dry to size of valleys. then start laying in. like other said you can start a fire, and larger patch size =more bonding area. good luck

[bulldog_shotgun 47]

worked on a fiberglass hood on one of our semis the last several days.(used to work in a bodyshop)

 

i glanced at your linked article it appears mostly correct.

 

i usually use a 4.5" angle grinder with a stainless wire wheel to really hog out the hole (gloves long sleeves and safety glasses) you want to feather the edge about 1.5"'s for every 1/4" of thickness then i use a 60 grit on a DA thats locked out or a rotary sander. to give it some texture. you want to make sure you remove any fiberglass that has cracked or seperated between layers. and finally remove just the gelcoat from an area approx 2" farther. make sure to wipe down and remove dust.

 

back it up with tin, carboard, wood, or even ducttape.if you cant get to the back depending on how large the cavity is i have filled them with foam first, or try using cardbaord superglued onto the backside of your existing fiberglass.

 

there are 2 types of glass Chop Mat and Woven Cloth. start with chop finish with Weave.build it till its just below the surface then use weave to bring it just level with surrounding area and finish with one layer of Weave layed 45 degrees from the first that covers almost to the edge of your gelcoat

 

youll want gloves, mixing cups, stir sticks, chip brushes.

 

work in small batches it will cure not dry, (thats a pet peeve of mine resin cures or hardens not drys) fairly quickly if your in the sun even faster. when you mix MEKP (MethylEthelKetonePeroxide) with resin it creates an exothermic reaction. as others said if mixed incorrectly it can ignite you want it to get warm to very warm but not burn yourself hot. take your time depends on your resin for recoat times so check. make sure your mat is soaked thoughly but you dont want a puddle on top, work all air bubbles out with a stippling motion.

 

if you have any questions ask.

[IndyArms 10,186]

Thanks for the tips so far... problem is this area is not a deck, its up on the side like where the seat back of the cockpit is... up near where the cabin starts... I can kinda get in from underneath through the hatch for the gas can and battery... but I need monkey long arms to reach up to the hole from the angle... maybe I can get something rigged up on a stick and stick it up in under the hole for a good proper backing.

I watched a lot of videos about the small pieces of rough mat and making them bigger, as well as removal of ll the rough stuff down to good solid points. I just gotta remember its not a job you rush... but to take my time and let things happen... air pockets and excess resin are NOT your friend...

 

 

[mogunner 240]

I've done a shit-ton of fiberglass work over my long and varied life, and pretty much any of the above mentioned methods will work fine for what you want. Use a nice thick backer made from marine grade plywood though, I wouldn't recommend wood itself as it'll swell with moisture and even a little bit can lead to cracks, the glue in the marine grade will seal it, and plywood will expand and contract pretty much the same rate as the fiberglass which is why it's used so much in industry.

 

When you get to the mat/cloth stages, I've always been partial to making a base with the cloth and then switching to the mat as you can sand and shape the mat a lot easier without compromising the build you're working on, and work in another layer with resin and a stiff brush a lot easier until you've got it to where you want it. I always try and make the patch stronger than the original was, I've done pretty much everything from semi truck body parts, kit cars, even rebuilt a shattered outboard motor cover that a tree fell on that the owner couldn't get a replacement for. Good stuff, but messy.

[IndyArms 10,186]

Use a nice thick backer made from marine grade plywood though, I wouldn't recommend wood itself as it'll swell with moisture and even a little bit can lead to cracks, the glue in the marine grade will seal it, and plywood will expand and contract pretty much the same rate as the fiberglass which is why it's used so much in industry.

 

 

 

Thats the bummer... I only need a piece about 4 inches wide and a foot long.... I hate to buy a whole 8 foot sheet for just a little piece... I was hoping to get away with a small piece of standard treated plywood... It doesnt have to LAST forever.... just a few years. LOL!!! Its also not going to be structural... just a base for the patch...

 

[eva-u 2]

The best thing to use for secondary non chemical bond is epoxy resin. There are a couple of industry standard brands "West Systems" and "System 3". These will give you a much better mechanical bond to polyester resin based boats. You will have not much chemical bond since the poly in the boat has cured long ago. Gugeon Brothers has a great repair video online "West Systems" that will show you how to repair your boat correctly. Use a few layers of mat then go to a DBM cloth for maximum BI axial strength.

 

Epoxy is expensive but it is the king of the street for mechanical bond strength. The next best is vinylester for bond strength followed by ISO.

 

Look up those videos by West Systems . It will help a lot.

[IndyArms 10,186]

The best thing to use for secondary non chemical bond is epoxy resin. There are a couple of industry standard brands "West Systems" and "System 3". These will give you a much better mechanical bond to polyester resin based boats. You will have not much chemical bond since the poly in the boat has cured long ago. Gugeon Brothers has a great repair video online "West Systems" that will show you how to repair your boat correctly. Use a few layers of mat then go to a DBM cloth for maximum BI axial strength.

 

Epoxy is expensive but it is the king of the street for mechanical bond strength. The next best is vinylester for bond strength followed by ISO.

 

Look up those videos by West Systems . It will help a lot.

 

 

Thats all well and fine... but remember... this is a 4" x 1.5" hole in a non weight bearing, non structure area. Its almost a cosmetic only fix. I dont need to spend more on the hole than I did on the boat with all the latest and greatest resins... It just needs to not be a hole. Not better than new... The advice is appreciated, I think thats just overkill for what I need done. Hell... I dont even CARE if the gelcoat color doesnt match... No one on the boat will care either. LOL! I may not even PUT the cleat back in... and just say screw it after the hole is patched.

 

 

[mogunner 240]

Well, hell, just put a mini-gun mount in the hole then...