Blue Heron
Guru
I have spider cracks in gel coat in a couple of spots and the main one that needs to be fixed is on a step up to the fly bridge. What do you all recommend to address this?
thanks!
BH
thanks!
BH
Spider cracks in Gel coat
- Thread starter Blue Heron
- Start date
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Forkliftt
Guru
- Joined
- Oct 6, 2007
- Messages
- 2,450
- Location
- USA
- Vessel Name
- KnotDoneYet
- Vessel Make
- 1983 42' Present Sundeck
BH- I have some areas with spider cracks as well. Most are in or near the side decks which is the original non skid. They haven't gotten worse in 6 years, but when I get around to the repair I plan on using a product called Gibco flexmold. I think the prober approach would be to "router out" the cracks, mix the correct color gelcoat and pour in. Then overlay the flexmold to get the pattern back. Let us know what you do and how it works.
We’ve a few spider cracks in areas where some of the railing stanchions’ torpedo bases are bolted on, especially at the stanchion areas most often leaned-hard against. With clear silicone I pressure fill cracks then wipe surface clean with acetone. As our Tolly stays in covered berth now, and did so mostly in PO years, there are few cracks any place else.
Note: A main reason we did not purchase a 1976 48’ Tolly (our 34’ is a 77) was due to the uncountable (thousands) of cracks (small and large) throughout all its decks. There were notable soft spots too. Although it was from an orig owner who loved his boat, we learned that Tolly had spent its life non covered in summer blazing sun and winter weather conditions. Moral of the story... Cover Em if Possible - - > They Age Better!
Note: A main reason we did not purchase a 1976 48’ Tolly (our 34’ is a 77) was due to the uncountable (thousands) of cracks (small and large) throughout all its decks. There were notable soft spots too. Although it was from an orig owner who loved his boat, we learned that Tolly had spent its life non covered in summer blazing sun and winter weather conditions. Moral of the story... Cover Em if Possible - - > They Age Better!
I think spider cracking is usually caused by stress such as hardware tightened too tight or that's been loaded more than it should have been. I have spider cracks around some of my rail fittings and I have some where it appears the boat hit or was hit by a dock or another boat.
The repair proceedures I have read about require digging out the crack with a sharp tool to a "V" shape and then filling the crack with color matched gelcoat. Since the "pro" at my marina was unable to match my gelcoat, I have been hesitant to try this myself so I've just let the cracks be.
There's a product in a small tube, available at West Marine for about $12 that's supposed to fill these cracks. I haven't tried it.
The repair proceedures I have read about require digging out the crack with a sharp tool to a "V" shape and then filling the crack with color matched gelcoat. Since the "pro" at my marina was unable to match my gelcoat, I have been hesitant to try this myself so I've just let the cracks be.
There's a product in a small tube, available at West Marine for about $12 that's supposed to fill these cracks. I haven't tried it.
RT Firefly
Enigma
Greetings,
Mr. Art. The LAST thing I would EVER put ANYWHERE on a boat is silicone! Woe be the next owner or you, for that matter, if you ever want to paint. There are several clear "filler/sealers" available without having to resort to silicone. I have been using one (can't for the life of me remember the name but it does have an X in the name) type successfully around the glass/teak interface on the windows for several years now. Silicone-Bah!
Mr. Art. The LAST thing I would EVER put ANYWHERE on a boat is silicone! Woe be the next owner or you, for that matter, if you ever want to paint. There are several clear "filler/sealers" available without having to resort to silicone. I have been using one (can't for the life of me remember the name but it does have an X in the name) type successfully around the glass/teak interface on the windows for several years now. Silicone-Bah!
TY for the caution RT - Re thin spider cracks and silicone - if paint is desired the thin crack would be quick and easy to reem out for filling with "paint acceptable" filler-material prior to painting. In mean time a good quality clear silicone works great for long term to stop moisture intrusion into deck, virtually unnoticable too. Surround area was carefully cleaned with acetone at time of any silicone injection.
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I have to agree that silicone could be a problem in the future. It's nearly impossible to remove all traces of it and nothing sticks to it.
RT Firefly
Enigma
Greetings,
Mr. Art. Good luck with THAT approach! Mr. rwidman. Yes it IS nearly impossible to remove all traces. The ONLY solvent I am aware of to clean silicone contaminated objects well is Toluene.
http://avogadro.chem.iastate.edu/MSDS/toluene.htm
This is a chemical I have NO desire to handle without strict safety precautions!
Sorry Mr. Art. Acetone just won't cut the mustard.
Mr. Art. Good luck with THAT approach! Mr. rwidman. Yes it IS nearly impossible to remove all traces. The ONLY solvent I am aware of to clean silicone contaminated objects well is Toluene.
http://avogadro.chem.iastate.edu/MSDS/toluene.htm
This is a chemical I have NO desire to handle without strict safety precautions!
Sorry Mr. Art. Acetone just won't cut the mustard.
Steve
Guru
Creeping Crack Cure, this product has been around for years. Has anyone tried it,?
Here is a link
Capt. Tolley's Creeping Crack Cure
Steve W.
Here is a link
Capt. Tolley's Creeping Crack Cure
Steve W.
jeffnick
Guru
Capt. Tolleys is a thin latex based white fluid. It would take many applications to 'fill' a spider crack, but even just a couple applications I would think would seal, but the stuff is so thin that there's no mechanical stability.
If putting something in/on a spider crack would make you feel better, you might try this Locktite stuff...it's similar but thicker.
Personally, I don't worry about spider cracks.
If putting something in/on a spider crack would make you feel better, you might try this Locktite stuff...it's similar but thicker.
Personally, I don't worry about spider cracks.
CPseudonym
Moderator Emeritus
I was given the same advice regarding the spider cracks on our sailboat.
We used the point of a cut off 10 penny-nail in a Dremel tool to open up the cracks and filled with 3-M Marine Filler. It sands real easy. Then we sprayed matching gel coat using a Preval spay gun kit. Wet sanding will finish it. There is lots of information on the internet on the small details. We used styrene instead of acetone to thin the gel-coat as per the glass guy. He mixed a liter gel-coat to the existing color. We probably could have sprayed half the boat with that much. Once you get the hang of it, the results are amazing.
http://www.jamestowndistributors.com/userportal/show_product.do?pid=2155
http://www.jamestowndistributors.com/userportal/show_product.do?pid=2155
In basics I agree, re no worry on spider cracks... I only filled the few spider cracks that appeared large enough to leak. One I knew was leaking. As we dock in covered berth and usually have no need to cruise or anchor-out during rainy season, so moisture intrusion is limited on our Tolly... for sure. Thanks everyone for warnings and product suggestions.
BTW, RT - Early 1970's we used toluene by the 55 gal drum while building FG boats. I still use it diluted in fuel lines for cleaning purposes. I like the Big “T”... works well!
jeffnick
Guru
Toluene was a main ingredient in our gravure inks. When cleaning the press we'd have it running down our arms to the elbows and beyond...we'd wash our hands in it to get the ink off...we'd get high from the fumes. That was almost 50 years ago, and may explain a few things I have going today?
Toluene - Wikipedia, the free encyclopedia
Work in well vented space, do not inhale (snort) it, and use appropiate gloves... toluene is then not all that dangerous. It has many good uses.
Work in well vented space, do not inhale (snort) it, and use appropiate gloves... toluene is then not all that dangerous. It has many good uses.
Blue Heron
Guru
Jeff,
My concern with the spider cracks are on a load bearing step..
My concern with the spider cracks are on a load bearing step..
Blue Heron
Guru
too many others on the boat to give an obama about...
jeffnick
Guru
You might consider the cause of the cracks....flexing? and fix the cause before you fix the effect.
psneeld
Guru
probably the reason they are there....hairline cracks are probably gel coat...anything wider and you have to remove some gel to see if the crack goes into the laminate.
chances are they aren't the cause of leaks...so true repair is only necessary if they will be exposed to freeze/thaw cycles that will aggravate them or untill you can see they are opening from the loading cycles.
JAT
Guru
Just prior to painting the topsides of our boat... I gouged out some spider cracks and filled them with West Systems with fibers mixed in, sanded the repairs smooth...painted and haven't have any of them reappear and its almost a year now.
FF
Guru
- Joined
- Oct 12, 2007
- Messages
- 22,552
Not where I have ground down and strengthened with epoxy and glass...that's about the only thing unless you can reduce the stress with another engineering solution.
Exactially!
The cracks are symptom of an overload , and the distressed under structure must be repaired , and then made stronger if the cure is to last.
FF
Exactially!
The cracks are symptom of an overload , and the distressed under structure must be repaired , and then made stronger if the cure is to last.
FF
Some of my cracks are symptoms of an unexpected impact (with another boat or a dock) so as long as that is not repeated, a simple crack repair should take care of them.
Others seem to be caused by hardware that was tightened too tightly so again, I suspect a simple crack repair should take care of them.
Unexplained cracks should probably be investigated before being repaired.
I have read the same thing.
psneeld
Guru
OK class...as posted on page 1...
"probably the reason they are there....hairline cracks are probably gel coat...anything wider and you have to remove some gel to see if the crack goes into the laminate.
chances are they aren't the cause of leaks...so true repair is only necessary if they will be exposed to freeze/thaw cycles that will aggravate them or untill you can see they are opening from the loading cycles. "
Without going UNDER the gel coat..you have no idea what's going on...if the laminate is cracked...it usually has to be repaired or the gel will just crack again...whatever the cause of the crack...
"probably the reason they are there....hairline cracks are probably gel coat...anything wider and you have to remove some gel to see if the crack goes into the laminate.
chances are they aren't the cause of leaks...so true repair is only necessary if they will be exposed to freeze/thaw cycles that will aggravate them or untill you can see they are opening from the loading cycles. "
Without going UNDER the gel coat..you have no idea what's going on...if the laminate is cracked...it usually has to be repaired or the gel will just crack again...whatever the cause of the crack...
