Repairing Spider Cracks in Gel Coat

Hairline spider cracks must be opened wider and filled with an epoxy filler to be permanently repaired. Learn how in this tutorial with Andrew Price.

[@TheDadofThem]

I had a repair shop for 20 years. We found that spider cracks almost always come back. This results in a very unhappy customer. If you can’t get behind the fiberglass and add some structure, the part will continue to flex and the cracks will come back. We all ultimately just decided not to take those jobs on anymore because it was a guaranteed dissatisfied customer.

[@Bakanelli]

You mean to put a layer of fibreglass over the top of gelcoat or did you mean to put it under the existing fibreglass to reinforce the core ?

[@filibertobarrera3839]

Holy rusted nails Batman ,that is Alot of stress cracks.But looking good .Reading comments on that you should of gone through the back to apply matting.Halarious almost chocked laughing.they don't understand that the customer would have a heart attack seeing an extra 4000 bill for matting the back in areas that aren't accebile.

[@JOEGGGJOE]

I’d glass the back of the spider crack. I never liked mixed epoxy with polyester. Seems like a good product but I’d probably just mix a peanut butter/slurry. I also think gel coat is usually put on too thick.

[@SunRa-]

Stress cracks in gel coat can come from extreme changes in weather also.

[@thaddeauscaldwell7101]

Great video . Two thumbs up 👍 👍. Do you have a video , where you are actually making the cracks wider . I'd like to see it done . What tools can I use to make the cracks wider ? Also , I have a fiberglass car body and the body has lots of hairline cracks . I want to repair the whole body the first time . Should I take off all the gel-cote and then fix the cracks and then re-gel-cote the body? Any advice that you can tell me , is greatly appreciated. Thank you .

[@craigmonteforte1478]

Great Video ive had good success using other Total products from Jamestown Distributors on my boats i fully understood you were prepping that Vessel for a Awlgrip job would there be advantages to applying another Gelcoat over the paint ? Just curious more than anything as i do know the advantage of future touch ups or matching with paint is usually easier and or would those same areas be more prone to re stressing cracks because of the overall weakness in that area either from Engineering or heavy use i had a 30 ‘ Sea Ray that. Always got Stress Cracks in the Cabin roof or bow area from people always loading and unloading their heavy coolers and. Equipment onto the boat there i eventually turned my boat around in the Slip to sort of force people to use the Stern and Swim platform which lowered the stress cracks Over time and sold that boat anyway due to Boaters disease Two Footitus ! As we need that extra couple of feet on the next one to get the extras we think we need !

[@gonza-fish5280]

Hello my friend, interesting content, like 👍👍👍

[@Burritosarebetterthantacos]

my sailboat has so many cracks I thought it was part of the design scheme!

[@luisroebuck4354]

tank you for sharing your knowlage , much needed

[@generationfunk]

would have been nice to see the end result, or at least the middle?

[@yachtorial2809]

Watch "Telstar 28 Restoration" video for the end result on Yachtorial channel. Sorry for the late response.

[@robertcain3426]

Apart from too light a laminate resulting in flexing, cracks are also from too thick an application of gel coat - gel-coat will not flex very much and so crack. So fixing the cracks is just merely a cosmetic fix. You need to fix the real cause.

[@johncampbell3356]

Good tips

[@dipakparmar3779]

Hi I am Dipak ,is it use for wind blades or in frp I want to repair the blades

[@elijahmerrill9045]

It should be noted that that fairing compound will not work with Totalboat gel coat. Learned that the hard way. You’d think Jamestown would state that on their website, or warn you when you buy two incompatible products.

[@rocketagp]

Elijah Merrill That is an unfortunate flaw in their otherwise good line of products! Thanks for the heads-up! This project was painted with Awlgrip subsequent to repair. The project turned out nicely!

[@chriscalabrese9099]

It actually isn’t a flaw at all. You can’t lay a polyester over an epoxy. That’s something you should have known with experience.

[@jamesdow4866]

Gel can be applied over just about any epoxy. I buy from Jamestown daily and forums out the hard way total fair is incompatible no matter what you do or add to the gel. I have sprayed gel over thixo hundreds of times with no issue

[@jjp4119]

GM How are those spider cracks holding up on Total Fair filling? I'm cosidering Total Fair filling myself. Ty.

[@yachtorial2809]

That boat was sold years ago and although I produced the video, I have no contact with the owner.

[@BluesmanSLC]

I have an insane amount of cracks on the gel coat as well as the rest of the boat from top to bottom. Do I drill them ALL OUT and use your same filler?

[@yachtorial2809]

Marine supply stores offer fillers to apply over spider cracks, but the only way to insure that they don't reappear is to widen the crack, then fill it as seen here.

[@rocketagp]

Stephen Holt if you have a great number of cracks, your gel cote may be “checking.” It occurs from age, weathering, sunlight, and temperature change that causes the gel cote to crack into small, irregular squares. In this case, the remedy is to grind down or completely remove the gel cote and re-gel cote the boat. That was not the case with this project. -Andrew

[@diastoleny]

Helpful. Thanks.

[@andremarais2706]

The glass is thin and flexes too much. This causes the crazing/cracking. With such extensive cracking, at least thickened epoxy should be laid in first. These cracks will reappear on either side of the repair.

[@1UTUBEUSERNAME]

I agree. They will telegraph through in not time. I'd like to see the boat now to see if the repair held up.

[@rocketagp]

1UTUBEUSERNAME we reinforced the decks where flexing occurred. Other areas have shown no degradation of the repaired cracks.

[@rocketagp]

1UTUBEUSERNAME also, “print” or “printing” is the term for cracks or other problems which are covered but can be seen through or beneath the repair. -Andrew

[@rocketagp]

Andre Marais the filler IS thickened epoxy. I could have made thickened epoxy myself, but buying it is easier and ensures more consistency. After two seasons, the filled cracks are fine. The paint is in excellent condition. The boat was made to be very light. The vacuum bagging process results in a thin hull. Most of the glass in this boat was not cored as is common to reinforce sailboat decks. We reinforced some decks and joints with biaxial mat.

[@darrrenbetker4266]

Ok. Thanx

[@dipakparmar3779]

I want to buy this type materil or putty or filler so how can I buy this from India and my question is what is the minimum order quantity

[@yachtorial2809]

We don't sell products. The Total Boat products can be purchased through Jamestown Distributors. www.jamestowndistributors.com

[@bcain5823]

The instructions on the fairing compound recommend sanding prior to applying. What grit sand paper would be good for that?

[@yachtorial2809]

It would depend on what kind of surface you're sanding. Fairing compound will stick better to surfaces that are mildly roughed up and not extremely smooth.

[@cepuras]

Thats a lot of cracks.. What year and brand is the boat?

[@rocketagp]

cepuras it is a 2005 Telstar 28 trimaran. It was one of the first vacuum bagged production boats made, and this hull was an early number. Hence, I estimate the factory was working out the process. The build is very light, 3000 lbs for a 28 ft boat! It is sturdy, but light. -Andrew

[@JetDriver1111]

Although the fairing compound you are using works well, it is not easy to sand,, even with autobody DA sanders...I've been doing this for 35 years....It also takes forever to harden...24 hours at 70 degrees F and really about 48 hours at 70F to sand it...

[@rocketagp]

JetDriver1111 that is correct! However, an orbital sander with a succession of grits will take it right down. An ocillating tool works for the tight areas. -Andrew

[@2justinpjoyce]

Can you gelcoat over that epoxy filler or only paint over?

[@yachtorial2809]

According to an online search, polyester gelcoat can be used over Epoxy.

[@darrrenbetker4266]

why cant you fill the cracks with resin?

[@rocketagp]

Darrren Betker The cracks will have contamination in them, which will weaken the resin and prevent it from filling the cracks. Also, the straight epoxy will not be as strong as filled epoxy. Additionally, if un-drilled, the cracks will be unlikely to fully fill the cracks. If the surface is to be repaired, unfilled cracks will reopen.

[@darrrenbetker4266]

@@rocketagp so if i use a dremell to open up the cracks then can i use resin to fill them? Please respind quickly as im going to be doing just that starting tomorrow.

[@rocketagp]

Darrren Betker yes. First, wear a respirator mask, eye protection, and a dust suit! Use the Dremel 9910 Tungsten Carbide Cutter bit. Grind the crack by gently laying the bit into the crack and cutting along the crack down to the fiberglass. The opened channel will be 1/8” wide and show the fiberglass below. Do no cut into the fiberglass. Only remove the gel cote. You will draw the dremel, laying it at a low angle along the crack. I use one hand to hold the dremel and the other to steady the bit. Once you finish opening the cracks, blow out the dust. Then clean the boat with acetone to remove dust and dirt in the cracks and on the boat. Thanks for asking! -Andrew

[@rocketagp]

Darrren Betker ....about the resin... I would use thickened epoxy because resin alone will run and make a mess. Additionally, the thickened epoxy will have better structure. You could thicken epoxy using a product like the West system with either light or heavy weight filler, but I recommend buying filler like the Total Boat product. It is thickened epoxy that is going to be perfectly consistent for you. I recommend making a mixing board you can wear over your thumb, like one you would see an artist painting with. I mix on the board, slip it over my thumb, and carry it on the boat while filling the cracks. Spread the filler in 2 directions to be sure you get any air out. Do not leave a big buildup over the crack, but do not dig the spreader into the cracks. Sand the filler down to even with the surface after it cures. You will find that a second application may be needed to get the level surface you want; otherwise, you may get some “printing” of the filled channel through your final painting or gel cote. -Andrew

[@johnkealohafero8900]

So it's not necessary to have to redo all the gel coat ?

[@yachtorial2809]

We did not do gel-coat because of the extent of the repairs, the desire to have a new color, and nature of the problems with the original gel-coat. If you choose to gel-coat, you would only open the cracks down to the fiberglass and then apply gel-coat. You would apply gel-coat until it is slightly prominent, and then sand it back to the level of the surrounding gel-coat.

[@johnkealohafero8900]

@@yachtorial2809 I only ask because I have a small Hawaiian canoe hull and was thinking about fixing it up as there are cracks in the get coat but I was told I have to sand down the whole thing past the gel coat if I wanted to fix it (guy that told me that I questioned what he knew) it seems I can fill spider cracks sand it down and paint it and call it good ?

[@glennmulhare9124]

With all those cracks and that gelcoat substrate so bad, why wouldn't you just sand the whole boat down to remove that bad gelcoat and then prime and paint. Whos to say that those cracks are the end of the cracking of that original gelcoat? And then after done and painted new ones appear.

[@sailjazzdew]

Good point

[@aarongary2438]

I have the same problem with my boat, how much filler did you use in total?

[@rocketagp]

Aaron Gary oh my! I used nearly 1 gallon of filler. Most of the cracks were small. It does not require much filler. -Andrew

[@fishmandad588]

Can u send me the website for filler ,because I need it very bad

[@yachtorial2809]

jamestowndistributors.com

[@bullhippo9023]

Too many cracks, hmm......perhaps more glass should be added?

[@broderickwallis6641]

Wheres Bernie Spooner???

[@darrrenbetker4266]

Good lord theres gotto be an easier way

[@johnabuick]

That seems like one helluva lot of cracks to fill, probably costs more than the boat is worth.

[@rocketagp]

johnabuick it would seem so, but it is an expensive boat! Additionally, it is a project for my wife, so my labor is free on this one! The boat turned out great, and it sails wonderfully. It looks nice too! -Andrew

[@timothymcguire7437]

Really??? Check out Yacht world for pricing...

[@michaelchase6013]

NOT the best way to fix cracks in gelcoat. He basically filled the cracks with body filler and will then paint over it. Anybody who paints over gelcoat is a fool, this is not fixing the gelcoat, just covering it up. Very amatuer/bad advice here.

[@alfasweden]

This boat needs structural work Fixing those cracks is a waste of time and money They will be back in a year or less

[@yachtorial2809]

FYI This tutorial is two years old and fortunately the spider cracks haven't returned. These videos have been made available to help anyone choosing to repair spider cracks and not for the reason that we think everything we do is the most efficient use of time and money.

[@robertcain3426]

@@yachtorial2809 the cracks have appeared for reason and perhaps you could address this in another video.

[@ryszardjacekrusniak7993]

Wrong... profit oriented bologny...

[@yachtorial2809]

Wrong... Not one cent has been received from posting any yachtorial videos. These repairs were done in 2017 and she's still holding up well. We encourage you to post your own instructional videos to further help the boating community.