Re-gelcoating your hull - PART 2 - fairing and spraying- [restoration of a sunfish sailboat]

In this video I cover the final sanding, applying totalboat structural repair putty, and some home made fairing compound. I use totalboat gelcoat and some silica to make my own. It's an alternative to poly fair if you either don't have any or are worried about sanding through. Spraying gelcoat can be a pain, but done in layers you don't have to worry. I'll show you in this video how to do it the right way. Repairing fiberglass cracks can be intimidating but trust me boat restoration is easier than you think. Ive done a few videos looking at spraying gelcoat, but this is the first one I've shown spraying a hull on camera. Thankfully my iPhone survived!
#boatrestoration #sunfishsailboat #holdfastmarine
If you have not watched the video on the cheap spray gun a link will be in the comments.
• Re-Gelcoating your hul...
Please help support the channel by subscribing and using the discount code holdfast10 at www.totalboat.com

[@TotalBoat]

Great video! Thanks for sharing your tips and tricks, it looks awesome!

[@floridasaltlife]

I am liking your channel, love seeing peoples take on how to do boat repairs.

[@HoldFastMarine]

Thank you.

[@thedirtybomb19]

I used to do fiberglass years ago. We used to just use everglass to do fills and then thin out the gelcoat with acetone to spray. Worked out great. My first time seeing it done this way. Looks great!

[@HoldFastMarine]

Much appreciated!!

[@BlakeBarrell]

Awesome 👌

[@doverivermedia3937]

Very interesting & insightful ! I'm about to embark on sorting out my Ring 18 over winter. Thanks for sharing your expertise ... 🇬🇧

[@HoldFastMarine]

Good luck

[@danielgrace7408]

Thank you for the video 👍👍👍👍

[@HoldFastMarine]

Thanks for watching!!!

[@paullahmers7939]

I'll be redoing bottom of bass boat reel soon so thanks it helped out alot

[@HoldFastMarine]

Best of luck! Thanks for the nice words!

[@kevinschneider7642]

I've painted hundreds of cars trucks and boats but never have done gel coat thanks for the help

[@HoldFastMarine]

Thanks for watching!!!!

[@Goran2551]

Great info ….i just bought a 1972 triton 26 ft….that will need a internal and external refurbish,,,,,,

[@KHtally]

Get the plastic can spout. Awesome.

[@kevinramey4226]

I love see you make a video using gelcoat over fiberglass that has bondoe on it , i am working on a kit car

[@HoldFastMarine]

I’ll give it a thought. Thank you.

[@kevinramey4226]

@@HoldFastMarine thanks

[@LifeOnTheHulls]

I use roll down plastic outoor cafe style blinds battened to the rafters and an extraction fan to deal with overspray.Blinds roll up in a minute and are totally out of the way.Available at any box store.Ross.

[@HoldFastMarine]

Those work great too!

[@MPrybil]

Seeing the condition of the boat you’re working on makes me feel better. I’m working on a 1968 Sunfish left outside in Arkansas for the last 5 or 6 years but it doesn’t have the hull damage yours does. Was the bailer already off when you got the boat? Mine is the metal bailer rusted on so have to cut it off. Luckily there are You Tubes to show me how. Glad to see you wearing a mask. You’ll be glad you did when you’re in your 70s!

[@HoldFastMarine]

I removed the bailer. These are not my boats. I hate sailing. They belonged to a Boy Scout camp. I wear a mask when I can! Thanks for watching and the great comments! I hope you subscribed!!

[@choimdachoim9491]

7:30 ish is an oil-painting and clay modeling blade. I've purchased them at Art Supply Stores and there are many variations.

[@nelloagostini4389]

Don't worry about hitting your I phone with overspray I've hit mine with a lot worse may of even thrown it a time or two. Boat looks good already

[@HoldFastMarine]

Lol. Well I don’t like spending 900$ on a new phone

[@FredPaulus-xw3iu]

I have an older boat that is very similar to a sunfish, and the bottom of the hull is in bad shape with spider cracks. Do I need to sand all of the old gel coat down to the fiber glass and then put new gel coat on ? Thank you for your response

[@superheyofficial]

Can i apply epoxy paint first before I apply the gelcoat final coat with wax? Please and thanks for the reply

[@HoldFastMarine]

No. Gelcoat will not adhere to epoxy.

[@michaelcole7659]

I've found your videos very informative. I'm restoring a fiberglass car body and made the repairs using powder-coated random strand fiberglass mat and epoxy resin instead of styrene to avoid the 'wax' the use of which intimidated me. My question is can I gelcoat over the epoxy repairs? I seem to remember an issue with epoxy in one of your previous videos. If I can't gelcoat what would you advise?

[@HoldFastMarine]

First mike, thanks for subscribing. I always respond to subscribers. To answer your question, you cannot put gelcoat (which is polyester) over epoxy resin. It just won't bond well. Your only option is paint now. Next time just buy poly resin with the wax included, then you won't have to worry about it!!.

[@together1423]

Sir thank thank you do have training classes if not you should make one

[@HoldFastMarine]

I do. They are all in person classes at my shop.

[@byebyeitguy]

Great Video but lacking info for me...What grit sandpaper are you using on the original gel coat? (The bulk of the bottom?) Is it 180 grit? 220 Grit? Can I use 180 for the first coat? I'm getting ready to re-gel coat the bottom of my 1978 GT150 GlastronCarlson and I am changing the color. The bottom is in great condition but the color is a putrid yellow that needs to go away. I am gel coating the bottom for the durability of have a tough surface on the bottom. I am planning on 2 coats of laminating and one or 2 coats of wax coat... But I need to know what you recommend for the initial sanding (what grit before gel coating?)

[@HoldFastMarine]

I use 80 grit for the prep work. Sometimes 40 if I’m in a hurry.

[@franciscotavares2817]

Awesome video, very informative, but I got a few questions. How much psi were you running for spraying the gel coat? and how far did you sand? Im trying to respray the hull of my old stand up ski and its got some decent scratches in it, would you sand it till the scratches are flat with the hull? thanks

[@HoldFastMarine]

All that info is in a .pdf on my Patreon page!!

[@piotrtrocki3842]

where are the links to all the products?

[@jackdexter2147]

Great video! What is the black stuff you rubbed on the boat before you sanded called?

[@HoldFastMarine]

It’s called a guide coat.

[@jasonsmith7809]

just wondering, does the polyester structural repair putty cure enough on its own to be able to sand? Or did you have to cover it with something to get it to cure without air? Thanks.

[@HoldFastMarine]

It cures for me, some people say it dosent. Give it the extra time to cure and sand it with 60,80 grit at a low speed.

[@redscorpionairgunner525]

boy, i have learned quite a lot. i am restoring a 1972 Hawaiian 21 ft. jet boat the gel coat is gone the metal flake is rough. where do i start any help would be greatly appreciated!

[@kennethbotkin5779]

A few years ago I restored my old Bahner flat deck. First things first was I repaired everything on the hull exterior. Then capped the rails (obviously not a necessary step) then got to replacing transom and stringers. Got all the dirty work done first. Then it was on to paint. In hindsight I wish I would’ve re-gelled it because it hasn’t exactly held up. Then built the engine and jet. Eventually I’ll get a new interior. But best of luck, my dad has a fully restored 75 Hawaiian

[@kentblairl]

Great info. What size/type compressor would be needed to spray gelcoat?

[@HoldFastMarine]

Depends on how much you have to do. The larger the area the more cfm you need.

[@popsoldboats3406]

You can actually use a small pancake as long as you follow a few basic rules.

[@popsoldboats3406]

When spraying you should never flick your wrist. It is all in releasing the trigger while still moving.

[@lordreginaldfilibuster]

that little puddy knife I believe is called a "Painters knife" or that's just something I've heard it refered to as.

[@HoldFastMarine]

Makes sense to me!! It’s a great tool for me!

[@rush164w]

I have some pretty Long and deep scratches down my hull. It's a 32' contessa. I'm unable to spray gel coat because it's in the yet other boats. What would be the best way for me to repair this? I have total bait gel coat and some pigments for color matching. Again the scratches are several feet long.

[@HoldFastMarine]

I would probably just apply the gelcoat with a brush. Maybe thicken it up a little with some cabosil or silica.

[@AndyHowe-ph2fz]

I just picked up an older sunfish that was, use the term loosely, repaired by the previous owner. He plugged the cockpit drain hole with fiberglass. Will that sand off?

[@HoldFastMarine]

Possibly. I’d need to see it to be able to tell you. I say just rip into it and see what happens!

[@gerardosullivan7126]

Great video mate! Whats the black dye that you spread that got into the scratches so you could see it when you were sanding? Cheers.

[@HoldFastMarine]

It’s graphite powder.

[@Pete-eb4ec]

And is that so you see where you've been or is it for a fine sanding?

[@williamlillie9309]

How much gel-coat does the average fiberglass boat use to cover a 12-15 ft boat? And is gel-coat "tintable" and can you add flakes to it to make it glitter?

[@HoldFastMarine]

You can add any color tint or flake to gelcoat. Sorry it took so long to reply!

[@toddpatane]

what are wiping on the hull as you are sanding, black stuff?

[@HoldFastMarine]

It’s called a guide coat. It’s pretty much graphite powder that when applied allows you to see scratches and low spots when you sand. The process is to sand until the black is gone. Then you know your surface is “flat” www.amazon.com/Mirka-9193500111-Guide-Coat-Black/dp/B00GTYHCGG/ref=mp_s_a_1_5?crid=18UEICE7NUEAE&keywords=guide+coat&qid=1650801015&sprefix=guide+%2Caps%2C74&sr=8-5

[@dl4922]

Ok! great video and good points to remember, I am re-gel coating my entire hull as well, but I need your input. I have sanded it down some previous small repairs were revealed because of small tiny air pockets and deep scratches. One spot is uneven needing fairing or leveling other areas are smooth and feathered out. what can i use for the uneven area I dont have silica? I am sanding to smooth with 180 grit should I go to a higher grit? and after fairing and sanding is it ok to blow dust off and wipe down with acetone and proceed with two layers of laminating gel coat without wax and final coat of gel coat with wax using Total Boat products ? I am at a disadvantage of completing the job from the bottom on a creeper by rolling will that be ok?

[@HoldFastMarine]

Buy polyester fairing compound. As far as the prep work before gel coating; you can use acetone but I don’t recommend it. And I won’t do a hull from a creeper, nor would I roll it. It’s going to be a lot of sanding

[@dl4922]

@@HoldFastMarine OK THANKS ! SO WHAT DO YOU RECOMMEND USING BEFORE APPLYING GEL COAT? DO YOU RECOMMEND SPRAYING IT?, I DONT HAVE A CHOICE BUT COMPLETE IT FROM BENEATH, MY BASS BOAT IS ON STANDS

[@HoldFastMarine]

@@dl4922 well TotalBoats poly fair is good stuff, if they have it in stock. Spraying is always better in my opinion but not everyone had the ability/equipment to do so.

[@redwood1957]

How do you decide when to use structure repair putty (what type) or just us a total fair compound? Thank you mike

[@HoldFastMarine]

Fairing compound is for making things smooth, structural repair putty is for… well structural things.

[@yavuzsan4921]

@@HoldFastMarine I used an epoxy filler for repair some staffs before coating with gelcoat. Was that wrong application? Thank you so much for the videos.

[@daallaassyy]

Can you start with the waxed gelcoat from the beginning of the coats? What's the difference between two coats non-waxed, followed up by 1 or 2 coats waxed vs all wax coats? Do you have to wait for each coat to dry/cure before the next one?

[@HoldFastMarine]

Laminating gelcoat is just that. The ability to laminate many layers without sanding in between. Waxed gelcoat cures hard, therefor if you apply it it will cure and you’ll have to sand before doing another coat.

[@daallaassyy]

Thank you!@@HoldFastMarine

[@connorwhitaker610]

How would you recommend doing it with a roller? 2 or three coats of gel coat and sand inbetween coats. Then do a coat of gel coat with wax?

[@HoldFastMarine]

You can’t sand gelcoat without wax easily. It gums up the paper very quickly. If you want to sand just use gel with wax.

[@connorwhitaker610]

@@HoldFastMarine I got the topcoat gelcoat that has wax with it

[@Jason-zr6il]

If you were to spray gelcoat with wax, how much working time you would have?

[@HoldFastMarine]

In the cup it’s the same regardless of wax or not. On the surface of the boat it’s a hour or two before it starts to gel. You only have 10 minutes or so in the cup.

[@makingcookingfixing]

Hi, thanks for your videos, I noticed with your catalyst calculation for your gelcoat putty, that you included the silica in the measurement for the catalyst? If you used 2 oz gelcoat and 2 oz silica, shouldn't you use just catalyst for the 2 oz gelcoat only? Genuine question, thank you.

[@HoldFastMarine]

Gelcoat is catalyzed by total volume.

[@makingcookingfixing]

@@HoldFastMarine By total volume of gelcoat I would imagine, not the inert material mixed in.

[@HoldFastMarine]

It is by total volume, including any pigment or anything else you add to it.

[@makingcookingfixing]

@@HoldFastMarine Hello and sorry again, but I checked everywhere and all resin suppliers say that the catalyst ratio is to the resin, not to the total volume. Mx the catalyst with the resin at 2%, then mix in your catalyst. I am. not being a pain, I just want to get the job done right and doing my research.

[@HoldFastMarine]

Your not being a pain. Not at all. In my experience (20+ years) I’ve found that total volume is better to catalyze at. Now, let’s be clear it’s poly resin right? So if you need to add 5cc or mekp and you add 8 or 4 it’s still going to cure. Sometimes just to get it done fast I’ll add 3-6 more cc than I need. It’s all About ambient temperature as well. If it’s a 90 degree day you need to mix at 1% or 1.5%.

[@JenkinsBoatWorks]

if you had it, could you have used TotalFair by Total Boat instead of your home made mixture? I get the idea that these boats are poly ester and not epoxy layup, and I have used TotalFair, a lot. thoughts? thanks, Chuck

[@HoldFastMarine]

Hi chuck. Total fair is epoxy based therefor the gelcoat will not adhere properly. Second total fair is not the best fairing compound out there. It's far too expensive for one, and really does not cure well. If you become a channel member you'll see why I'm not a fan of total boat anymore.

[@JenkinsBoatWorks]

@@HoldFastMarine Hi Will, I subscribed. interesting that you say this about TotalBoat. I have had some issues with several of their products an there are just other brands that are go to for me anymore, Epifanes for paint and varnish, west system for epoxy, that sort of thing

[@beachbum1808]

Random question! Redoing a small fiberglass plunge pool outdoors. Would you gelcoat it or use epoxy for the work?

[@HoldFastMarine]

Epoxy.

[@beachbum1808]

@HoldFastMarine ok and why is that man?

[@HoldFastMarine]

Because gelcoat isn’t strong. Nor is it 100% non porous. Make sure your subscribed to the channel please!

[@beachbum1808]

@HoldFastMarine will do thanks man! Its weird that its used for boats! Epoxy seems like a better option and easier to use

[@mitchgrant1963]

What is the black dust you put on the hull prior to sanding the bulk of the hull?

[@HoldFastMarine]

Well if you watched the video I explain what it is 🤣. But just for you I’ll tell you. It’s graphite powder.

[@mitchgrant1963]

I didn't watch in the proper order. I was just learning the answer on the next/previous video when your response came in. Thank you.

[@JFabrication]

Its called a "guide coat" to help show how much has been sanded off, you can use powder or even dust some kind of black spray paint over it, just be sure to remove it all especially if if its not a completely compatible material. This is very helpful for large jobs you cant observe all at once, or controlling how much you sand off with a visual marker. Just something that will stand out to the eye, black over white and light colors, light over black or dark colors.

[@thatrandomchannel8589]

Do you need to thin the gel coat to apply 2 layers?

[@HoldFastMarine]

Negative.

[@thatrandomchannel8589]

@@HoldFastMarine thanks

[@harbylimon8442]

How long after applying the fairing compound can you sand and shape?

[@HoldFastMarine]

Depends on many factors, temperature, humidity and how “hot” you mix it. Sometimes it takes hours, sometimes it takes 15 minutes.

[@harbylimon8442]

@@HoldFastMarine it was lest than an hour! That stuff didn’t even make it 15 minutes in the container before starting solidify. Went through almost the entire can. I appreciate the time you have taken to respond. Keep up the great videos.

[@HoldFastMarine]

@@harbylimon8442 well you mixed it too hot bud. Always mix either small batches OR use a bigger container. Polyester stuff is exothermic so the tighter it’s packed the quicker it sets. And thank you for the kind words!!

[@harbylimon8442]

@@HoldFastMarine yup, I found that out after the 4th attempt but I finally had it all in place and shaped out. It’s coming along but today I will be doing the gel coat. I have the foam roller and paint trays. Wish me luck, I’ll need it. Oh, I’m in south Texas where the humidity is high and the heat is crazy hot. Thanks again and any tips on the gel coat are greatly appreciated. Have a great Sunday!!

[@steveluera2109]

So, the thing about silica is that the particles have very ragged edges. If/when you breath them, as you did after taking off the respirator and blowing the dust into the air, they become embedded in the tiny sacs in your lungs. The sharp edges cut your lung membrane, causing it to bleed, ever so slightly. The healed scab turns to scar tissue, which prevents oxygen from crossing into your bloodstream, which is what your lungs are designed to do. Over time, as you breathe silica dust, your lungs become excessively scarred up, preventing oxygenation of your blood. You suffocate. So, if you work with silica a lot without the respirator, you're gonna strangle yourself. Just saying. If you also smoke, can you leave me your tools? And wife or girlfriend? I guess I'll have to wait a few years, though. And, I'm already old, so forget it. Breathe all the silica you like.

[@HoldFastMarine]

👍🏼

[@craignmz5264]

I didn’t think you could put new gel coat over old gel coat?

[@HoldFastMarine]

You can

[@RCAVEMANS]

Dollar Tree has shower curtains for $1.

[@fairyjune749]

Is there a way to gelcoat without using a sprayer?

[@HoldFastMarine]

Yes there is, you can brush or roll it on. Be aware you want a thicker coat because you’ll be doing a LOT of sanding.

[@vdmmj]

Your other two videos are hidden?

[@HoldFastMarine]

What two other videos? There is only part one and two up now. Part three is coming but I keep getting copyright pings on free KZbin music… it’s been extremely annoying.

[@michaelwhite7704]

I was looking for number three as well. If you look at the sailboat playlist it says four videos but two are hidden. Nice work so far. I'm enjoying the channel. 👍

[@HoldFastMarine]

@@michaelwhite7704 I don’t know why it says that. Again I tried uploading the video and got pinged again. So I’ll have to re edit. I’m hoping it’ll be up by Friday. Sorry about all this.

[@michielderuyter6011]

The music is more worse than the fan😤 But otherwise a helpfull video and tnx for sharing.

[@HoldFastMarine]

not as bad as this comments grammar 🤣 and your welcome. thanks for watching, I appreciate you!!

[@ronjcav]

You use staff wo explaining what it’s for.

[@HoldFastMarine]

Like what?

[@malcolmzabaneh5977]

Making filler from gelcoat w/silica… You started w/2oz. gelcoat w/wax, added silica powder & mixed, then did some inexplicable calculations on calculator 🥴 which concluded in your adding 5 OZ.(!?!), of catalyst… Really??? What’s up with that? Seems like 10 times too much or am I missing something here?

[@HoldFastMarine]

5cc not 5 ounces.

[@davidbryant3131]

Dude, love your content, but Jesus, you need to put on a mask!

[@HoldFastMarine]

lol. Maybe.

[@markkraus3598]

Question- what’s the differences/ advantages of using wax vs no wax gel coat ? Thanks

[@peterbridge9394]

@markkraus3598 Mark, I'm learning this myself, so you must research and confirm what I tell you. I think that wax gel coat is a final coat only. I don't think that you can go over a wax coat, and if you need to go over a wax coat, you have to prep first to remove the wax. I think that a first coat will always be no wax. See dl4922 comment below, and also read the Total Boat product descriptions.

[@oldricky]

I lost a gun attempting to spray gelcoat only getting a small area sprayed before the gelcoat went off. The catalyst was carefully measured according to the weight of the gelcoat as per manufacturer's instructions at 1% ratio. So how is it you get to spray the entire boat which appears to exceed the 10-12 min gel time?

[@HoldFastMarine]

Small batches. 20 oz or less. Also gelcoat needs to be catalyzed at 2% by volume NOT weight. I have other videos explaining how that all works.