Spider Cracks and gouges

Woodonglass

Supreme Mariner
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Dec 29, 2009
Messages
25,929
Re: Spider Cracks and gouges

Trying to match the old oxidized gelcoat will be next to impossible. Fixing that last posted gouge will be the same techniqe. I'd add some cabosil to the ballons to make it set a bit harder. If you're not satisfied with the "Polka Dot" finish you get once it's all cured. You can always paint.
 

Raschoony

Seaman
Joined
Jul 3, 2013
Messages
74
Re: Spider Cracks and gouges

ugh.. another thing...
Phenolic Microballoons
(BJO-0930)
These red/purple color phenolic spheres when mixed with epoxy resins will create a low density paste compound which will sand easily and improve strength/flexibility of the cured resin. Better for large gap filling.

** Use with epoxy resins only**

Is the epoxy resins its asking for the cabosil... sry dont really understand this stuff...
 

jbcurt00

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25,111
Re: Spider Cracks and gouges

no
cabosil is another type of filler

if you intend to try & make the repair using gelcoat, you shouldn't use any epoxy. Gelcoat doesn't adhere well to epoxy, but based on WOG's previous advice, you'll be using gelcoat & glass bubbles:
[SIZE=-1][SIZE=-1]3M Glass Bubbles
These hollow glass microspheres can be added to any epoxy and polyester resin. These bubbles will make a lightweight, easy sanding putty for minor surface filling of cracks, holes, etc. (Color: White)[/SIZE]
[/SIZE]
 

britisher

Petty Officer 1st Class
Joined
Feb 23, 2012
Messages
369
Re: Spider Cracks and gouges

I have an 89 SR 180 BR and have exactly the same spider cracks. I Googled quite a bit to find out the best way to repair these things. Apparently they are caused by stress. Old boats (I guess mine is 'old) used thicker glass fiber in the construction and hence flex less. Newer boats have thinner glass fiber and handle stress better.

Anyhow, the upshot was that the best way to repair them was first to grind them out in a V shape using a Dremel or similar (mine is a harbor Freight version). I did this on mine at the weekend. After cleaning the area thoroughly (cellulose thinners will do), use Gel coat paste to fill the gouge area. Cover with Mylar (this comes with the repair kits) or thin clear plastic sheeting from a sandwich bag or the likes to let the gel coat cure, then sand down and refill if necessary. Keep wet sanding with progressively finer grade, then buff out and job done. Because the Gel Coat paste is colored the same as the hull color, you probably will not be able to spot the filled cracks (famous last words).

All the articles I have read say DONT use Bondo or anything like that and DONT use poly resin, just use Gel Coat paste. You can buy ready made Gel Coat paste repair kits online and in stores (IBoats sells Spectrum brand). Spectrum is color mixed for various boat makes and manufacture years, so the color shade should most accurately match your boat (when it was new of course). Mine is Sea Ray Arctic White. Am I bothered to match the color on the 25 year old boat, that has faded anyway? Not really. Plain White will do for me.

Gel Coat paste is essentially Gel Coat mixed with a thickener such as Cabosil. You could mix your own if you want. From a personal perspective I always look at cost and from what I see the 2 OZ. Spectrum Gel paste is $25.00 plus shipping. How far will 2oz go? I have no idea whatsoever, but doesn't sound very far. Some articles say as far as covering and area of 10 silver dollars???? How useful?????

As an alternative, US Composites sell 1 quart of Gel Coat for $17.00 + shipping, so both work about the same dollar cost +/- a dollar or so. I know that I will have sufficient with a quart and I have lots of Cabosil left over from my refurb of the boat. Making my own is probably the way I will go.
There are lots of article AND videos out there for you to learn from.
 

Woodonglass

Supreme Mariner
Joined
Dec 29, 2009
Messages
25,929
Re: Spider Cracks and gouges

Ok here's what you need and don't need. You DON'T need Epoxy. You do need a quart of pure white Gelcoat and the hardener, 1 qt 3m glass bubbles, 1 qt cabosil. Mix up 1/2 cup at a time and use a bondo spreader or a plastic putty knife to fill the scratches and gouges. Make it just a bit thicker than Mayonaise. If working over head make it as thick as creamy peanut butter so it will stick well. Leave it "proud" of the surface so you can sand it smooth. YOu can get all of this from Fiberglass , Epoxy , Composites, Carbon Fiber - U.S. Composites, Inc.
 

Raschoony

Seaman
Joined
Jul 3, 2013
Messages
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Re: Spider Cracks and gouges

Thank you to all... seems like your all throwing elbows to get a turn to give people advise(I hope that translates correctly)... this community rocks so much... I'll be searching re-upholstery threads next...
 

Raschoony

Seaman
Joined
Jul 3, 2013
Messages
74
Re: Spider Cracks and gouges

Ugh again one last thing... hah

Was about to buy everything.. on the site for the gelcoat is says.."Please note: Our Surfacing wax (sanding aid) is required for your finish coat in order to sand/polish this product."

Is this needed in the list also..?
 

jbcurt00

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Re: Spider Cracks and gouges

Yes, you mix their wax in w/ their gelcoat. You're buying GELCOAT not gelcoat repair kits, which could be a gelcoat paste, rather then gelcoat, correct?

Are you familiar w/ the amine blush epoxy often gets when it cures? Sort of a cloudy haze? It is a by product of the epoxy curing.

To get the gelcoat to cure, you add wax to the last layer. It rises to the surface once the gelcoat is applied, and prevents air being in contact w/ the curing gelcoat. That's why gelcoat is listed as having an air inhibited cure.

If you apply a gelcoat that has wax in it, it cures and you decide you want to add more gelcoat, you MUST sand it first to remove the wax/amine blush. That's why most of us recommend getting resins & gelcoat w/out the wax already added (both are also available w/ wax already added) and adding wax to the layers that NEED it, rather then all of the layers.

^^^ Help???
 

jbcurt00

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Re: Spider Cracks and gouges

I think you can also skip the wax step & cover the repairs w/ plastic rather then adding the wax..

Wax paper or plastic wrap should work

Since you are doing several smaller repairs, plastic/wax paper might work really well.
 

Raschoony

Seaman
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Jul 3, 2013
Messages
74
Re: Spider Cracks and gouges

Well most of the cracks should only need 1 layer (I'll find out as I go I guess)..

-> cover the areas... does this require wax paper taped on all 4 sides over the gelcoat??<-

then wax/buff when i do the whole boat as normal....
 

73Chrysler105

Chief Petty Officer
Joined
Sep 10, 2009
Messages
407
Re: Spider Cracks and gouges

A couple of those gouges have fiberglass showing those need to ground down around it and to fresh good glass then built back up with some fiberglass and resin and topped off with some new gelcoat. Especially like in the pic with the blue stripe. The others everyone is spot on with their advise.
 

Woodonglass

Supreme Mariner
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Dec 29, 2009
Messages
25,929
Re: Spider Cracks and gouges

Sorry 73 but I'v not seen anything that requires what you suggest. The gelcoat paste with Cabosil will do the trick on everything I've seen posted. None of the exposed glass is fractured so no need to repair it. Just replace the missing gelcoat.

To the PO, another method to get the Gelcoat to cure is to use Poly Vinyl Achohol (PVA)and spray it over the final coat. Easy to apply and once cured it easily washes of with soap and water. You can get 16oz of it for $5.00 from USComposites.
 
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73Chrysler105

Chief Petty Officer
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Sep 10, 2009
Messages
407
Re: Spider Cracks and gouges

Sorry 73 but I'v not seen anything that requires what you suggest. The gelcoat paste with Cabosil will do the trick on everything I've seen posted. None of the exposed glass is fractured so no need to repair it. Just replace the missing gelcoat.

WOG these are ones I would be concerned with looks like there is loose glass in the pics.

 
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Woodonglass

Supreme Mariner
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Re: Spider Cracks and gouges

Ya know 73C on second thought, You got a good point!!! Good Eye!!!!! I too think a bit of dremel work and a bit of Resin and CSM might not hurt a bit on those two spots prior to applying the gelcoat.
 

Raschoony

Seaman
Joined
Jul 3, 2013
Messages
74
Re: Spider Cracks and gouges

435 Standard Polyester Layup Resin (Marine Grade Resin)?

Schoony
 

Raschoony

Seaman
Joined
Jul 3, 2013
Messages
74
Re: Spider Cracks and gouges

Ok just made the order... things came up and stalled me but I'm back on track..:
1qt white gelcoat
2oz hardener
1qt 3M glassbubbles
1qt cabosil
2oz Surfacing Wax
1yd 4oz E Glass Style: 1522 Plain Weave Thickness: 0.0059" (now that I look at that should i have gotten 3/4 oz CSM?!?UGH!)
1qt 435 Standard Polyester Layup Resin
 
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