Please note this thread has been inactive for 90 days. For the best results, please start a new thread.
Page 1 of 2 1 2 LastLast
Results 1 to 25 of 36
  1. #1
    Cadet
    Join Date
    Apr 2013
    Location
    Toronto
    Posts
    11

    Red face How do I gel coat my hull?

    Hi everyone, I'm new this this forum, I just purchased my first boat 14 foot fiberglass ( cottager boats) , my hull has lots of deep scratches all over the hull, I wanted to gel coat it using a roller and brush method, but don't know the steps involed,
    I have been reading and watching YouTube videos for the past 2 weeks, if any one has done this before please help.
    I would like to put a couple of coats on, my boats hull colour is white, and will be staying that colour. Any help would be awesome.
    Just want some info on sanding, cleaning hull with what solvent after sanding, then next step and so on.
    Thanks

  2. #2
    Commander
    Join Date
    Jun 2011
    Location
    Middle Georgia
    Posts
    2,027

    Default Re: How do I gel coat my hull?

    First of all welcome to iboats. Good to hve you aboard...

    Personally I have never used any Gel Coat for anything. I'm sure others will chime in here and explain the process. But I'm sure you will have to fill all those scratches first before applying anything over them. So be prepared for doing some sanding for starters. And remember that preparation to any finish is the key to how well it comes out. Anything you even think is not correct will certainly show through in the final finish... With that stated, you can make your new (to you) boat loook amazing I'm sure. And post some pictures to show everybody what you are dealing with for starters as well. Pictures convey a lot of info and are most of the time more informative then words...

  3. #3
    Vice Admiral tpenfield's Avatar
    Join Date
    Jul 2011
    Location
    Cape Cod, MA
    Posts
    5,885

    Default Re: How do I gel coat my hull?

    You might be able to get decent results from 'rolling & tipping' of gelcoat . . .

    your challenges will be:

    filling in the scratches gouges on the hull and getting it all smooth and sanded.

    Thinning the gelcoat properly so that it will flow out before hardening

    working in small batches and going fast enough so the gelcoat does not set up on you.

    Spraying is a better way to go, as the application can be faster than roller & brush.

    If your boat only has a few scratches, it may be worth doing individual repairs rather than a prep and coat. If the scratches are numerous and/or the existing gelcoat is in poor condition, then a re-coat would be the way to go.

    Post some pics as you go.
    Best regards,
    Formula 330 Sun Sport
    Twin Mercruiser 7.4 LX MPI (0F802036, 0F802039), Bravo 3's (0F806198, 0F806199)
    1969 Mercury 7.5 HP Outboard (26346XX)
    .
    My Formula 330SS Web Site: -> Link
    My Formula 242SS Web Site: -> Link
    My Catalina 22 Web Site: -> Link

    Member of the Month - February 2013 http://www.iboats.com/blog/tpenfield...-of-the-month/

  4. #4
    Cadet
    Join Date
    Apr 2013
    Location
    Toronto
    Posts
    11

    Default Re: How do I gel coat my hull?

    Thanks for the info, i prepared for sanding, i will be starting this project hopefully tomorrow, i just waiting for some friends to come by and help me flip my boat.i will post pics once i flip the boat. what do i use to thin out the gelcoat. the gel coat that im using is finish gelcoat. i just want to hopefully lay 2 coats down. After i sand is down what do i clean the hull with? just water and wipe it down,???

  5. #5
    Petty Officer 1st Class DeepBlue2010's Avatar
    Join Date
    Aug 2010
    Location
    Seattle, WA
    Posts
    385

    Default Re: How do I gel coat my hull?

    My advice would be to slow down a little and don’t take on this project until you are ready for it. No offense, but despite what you said about spending 2 weeks reading and watching how to videos, you still don’t know how to thin GC. As our gel coat experts stated in this forum multiple times, GC is not paint and it will not level as paint. Roll and tip results will be very questionable for GC. The one and only time Ondarvr (iBoats GC expert) OK(ed) it for someone, he was from England and the consensus were that GC in England is specially formulated for rolling. Other than that, I never came across an expert recommendation to roll GC. Read this thread, I do believe you will find it useful in your situation. Best of luck to you.



    http://forums.iboats.com/boat-restor...ed-465692.html

  6. #6
    Lieutenant Junior Grade zool's Avatar
    Join Date
    Aug 2012
    Location
    NJ
    Posts
    1,219

    Default Re: How do I gel coat my hull?

    You know, there is no rule that you have to gel over gel...most ppl choose a paint system...its usually more cost effective and the results can be VERY acceptable. Gelcoat makes a nice base to prep over so no need to remove it all. Look into Interlux Brightside or the like. Which ever you choose, try to stick with one product line for primer/paint/hardeners and thinners as they are chemically formulated to work together, the spec sheets provided by the manufacturer will advise which products work best with each other....Keep in mind the air temperature plays a roll in which accompanying products to choose, again, its all in the spec sheets.
    "We all come from the sea. But we are not all of the sea. Those of us who are, we children of the tides, must return to it again and again."

    Current Boats
    10' tin gamefisher/Johnson 7.5hp ob
    1991 Sea Ray 170br/AlphaMerc
    1996 Century 1800 CC/Yamaha c85
    1988 Imperial 280SF (under the knife)

    http://forums.iboats.com/boat-restor...cs-598307.html

  7. #7
    Lieutenant Commander greenbush future's Avatar
    Join Date
    Aug 2009
    Location
    Auburn Hills, mi
    Posts
    1,553

    Default Re: How do I gel coat my hull?

    Pictures of your project will really help the experts here, I'm not one of them, but I do agree that most of the projects that are finish related here are paint not Gel coat. I bet you will have better luck.

  8. #8
    Supreme Mariner Woodonglass's Avatar
    Join Date
    Dec 2009
    Location
    Broken Arrow, Oklahoma
    Posts
    15,622

    Default Re: How do I gel coat my hull?

    If you've never gelcoated you really need to research and study up on the application of it. It's totally different than paint. As others have said, for the DIY'er it's usually much easier to paint but, having said that, we have several DIY'er members who have done great jobs on gelcoating their hulls so it can be done by the diy'er too!!! You just need to know what you're getting in to before you attack it.

  9. #9
    Vice Admiral Yacht Dr.'s Avatar
    Join Date
    Feb 2005
    Location
    Michigan
    Posts
    5,349

    Default Re: How do I gel coat my hull?

    Quote Originally Posted by Snouch View Post
    Hi everyone, I'm new this this forum, I just purchased my first boat 14 foot fiberglass ( cottager boats) , my hull has lots of deep scratches all over the hull, I wanted to gel coat it using a roller and brush method, but don't know the steps involed,
    I have been reading and watching YouTube videos for the past 2 weeks, if any one has done this before please help.
    I would like to put a couple of coats on, my boats hull colour is white, and will be staying that colour. Any help would be awesome.
    Just want some info on sanding, cleaning hull with what solvent after sanding, then next step and so on.
    Thanks
    Hello mate and welcome to Iboats ..

    80 grit profile then acetone wipe . Mask off.. then spray your gel for 4 coats of a Medium to heavy spray.

    Wetsand and buff out the orange peel that comes with gelcoat. ( sometimes its starting with 320 or 400 .. depends on how well it sprayed on ) .. surely sand with 800-100- grit before you buff it out.

    PVA your sprayed on Gel .. when its just about Dry ...

    YD.
    Iboats Helper

  10. #10
    Captain friscoboater's Avatar
    Join Date
    Jul 2009
    Location
    Frisco Texas
    Posts
    3,074

    Default Re: How do I gel coat my hull?

    YD said it best. Don't be afraid of it at all.

  11. #11
    Cadet
    Join Date
    Apr 2013
    Location
    Toronto
    Posts
    11

    Default Re: How do I gel coat my hull?

    Hi
    Thanks for all the replys.

  12. #12
    Cadet
    Join Date
    Apr 2013
    Location
    Toronto
    Posts
    11

    Default Re: How do I gel coat my hull?

    5.jpg1.jpg2.jpg3.jpg4.jpgHi
    So I flipped my boat so I can start my project and notice lots of cracks also in the hull. So now I'm in need of some advice on how to repair the cracks. These shots are from my cell phone. You can't see the cracks, but theirs lots. I have circled in orange all the scratches and cracks area. So I think gel coating my boat would be a good idea.
    I have 120 grit sand paper, I don't want to sand it all down but just enough to make the gel coat stick to the hull. I will sand all scratches and cracks I little deeper. Then wipe down with acetone, then apply my first coat of gel coat, then sand again, and apply another coat and so on until I apply about 4 coats, does that sound right . Also I with be applying with a roller and brush? I own a automotive sprayer would that work, I know how to use it properly, just don't know if it would work with gel coat and how do I mix it so I can spray. Also Yacht Dr said it PVA after spray. What's PVA, lol remember I'm a newbie.

  13. #13
    Lieutenant Junior Grade zool's Avatar
    Join Date
    Aug 2012
    Location
    NJ
    Posts
    1,219

    Default Re: How do I gel coat my hull?

    Your right, I cant really see the cracks, but they may be just blisters. You may have to grind those down slightly to glass, then build them back up to flush, then fair them out smooth, or they may return.

    I would spray the gel since you have the boat flipped with good access. You will most likely need to thin the gel some depening on the tip your gun accepts. If you thin it with like Duratec, its a glossing additive that will thin it and give you a nice clear coat shine.

    Thats just my two cents, but the gel guys here will help you thru it all im sure. I like single stage 2 part paint, but thats just me...

    I sure with I didnt need to use bottom paint, I like the shiny bottoms with no cut line along the hull, but im in salt.
    "We all come from the sea. But we are not all of the sea. Those of us who are, we children of the tides, must return to it again and again."

    Current Boats
    10' tin gamefisher/Johnson 7.5hp ob
    1991 Sea Ray 170br/AlphaMerc
    1996 Century 1800 CC/Yamaha c85
    1988 Imperial 280SF (under the knife)

    http://forums.iboats.com/boat-restor...cs-598307.html

  14. #14
    Lieutenant Commander Decker83's Avatar
    Join Date
    Apr 2011
    Location
    Duncanville Texas
    Posts
    1,519

    Default Re: How do I gel coat my hull?

    Quote Originally Posted by Yacht Dr. View Post
    Hello mate and welcome to Iboats ..

    80 grit profile then acetone wipe . Mask off.. then spray your gel for 4 coats of a Medium to heavy spray.

    Wetsand and buff out the orange peel that comes with gelcoat. ( sometimes its starting with 320 or 400 .. depends on how well it sprayed on ) .. surely sand with 800-100- grit before you buff it out.

    PVA your sprayed on Gel .. when its just about Dry ...

    YD.
    You really need to listen to YD.. He knows what he is talking about..
    You can forget anything you know about painting because they don't apply to gel coat..
    The PVA is a chemical (in your case) that should be sprayed on after the gel coat is applied as YD has stated..Gel coat will not cure properly when exposed to the air.. PVA can be found at US Composite web site..

    When the gel coat is properly catalyzed it can be used for about 15 minutes making it hard to roll and tip.. Gel coat will not flow out level on its own making it hard to roll and tip.. Mixing to much at a time can shorten the time it takes to setup or kick..

    Gel coat is very expensive to use..

    I don't think you should roll on a coat and sand between them..
    Just my 2 cents..

    Good luck with your adventure..
    Just when I thought I was really learning, I continue to find out how little I really know.

    Project thread
    http://forums.iboats.com/boat-restoration-building-hull-repair/1983-deck-boat-transom-deck-stringer-replacement-help-471173.html

  15. #15
    Vice Admiral tpenfield's Avatar
    Join Date
    Jul 2011
    Location
    Cape Cod, MA
    Posts
    5,885

    Default Re: How do I gel coat my hull?

    Awlgrip may be a better approach than gelcoat . . . once you have prepped the surface and filled cracks, scratches, etc.
    Best regards,
    Formula 330 Sun Sport
    Twin Mercruiser 7.4 LX MPI (0F802036, 0F802039), Bravo 3's (0F806198, 0F806199)
    1969 Mercury 7.5 HP Outboard (26346XX)
    .
    My Formula 330SS Web Site: -> Link
    My Formula 242SS Web Site: -> Link
    My Catalina 22 Web Site: -> Link

    Member of the Month - February 2013 http://www.iboats.com/blog/tpenfield...-of-the-month/

  16. #16
    Supreme Mariner Woodonglass's Avatar
    Join Date
    Dec 2009
    Location
    Broken Arrow, Oklahoma
    Posts
    15,622

    Default Re: How do I gel coat my hull?

    You can't use an automotive sprayer for gelcoat. As previously stated, You really need to Read and Study up on the proper methods of applying Gelcoat. It's NOT like applying paint. You DON'T sand between coats. It's a polyester based product that sets up fairly quickly and goes on fairly thick. It requires a significant amount of sanding After it has been applied. Read and Study. That's my advice.

  17. #17
    Lieutenant Junior Grade idonthaveaname's Avatar
    Join Date
    Sep 2010
    Location
    Extreme South Florida
    Posts
    1,030

    Default Re: How do I gel coat my hull?

    Cute boat. I would paint it. Probably cheaper, faster, and less hassle. More time on the water. FWIW
    Yes I am a pirate, 200 years too late.

    Remember, if you are going boating -- take your boat. Don't ask me how I know this.



    Some men fish all their lives without knowing it is not the fish they are after
    Henry David Thoreau



    BUILDING A CENTER CONSOLE - LITTLE EAGLE RESTORE


    Little Eagle progress blog

  18. #18
    Lieutenant Junior Grade zool's Avatar
    Join Date
    Aug 2012
    Location
    NJ
    Posts
    1,219

    Default Re: How do I gel coat my hull?

    "You can't use an automotive sprayer for gelcoat"

    Well, he can per say...but only if his hvlp gun accepts a big tip,like 2.0+...2.5 would be best, and if hes fast enough to clean it between each fill before the thinned gel kicks......A cheap resin/gel spray gun would work better...
    "We all come from the sea. But we are not all of the sea. Those of us who are, we children of the tides, must return to it again and again."

    Current Boats
    10' tin gamefisher/Johnson 7.5hp ob
    1991 Sea Ray 170br/AlphaMerc
    1996 Century 1800 CC/Yamaha c85
    1988 Imperial 280SF (under the knife)

    http://forums.iboats.com/boat-restor...cs-598307.html

  19. #19
    Supreme Mariner Woodonglass's Avatar
    Join Date
    Dec 2009
    Location
    Broken Arrow, Oklahoma
    Posts
    15,622

    Default Re: How do I gel coat my hull?

    I stand corrected. This ^^^ is correct IF all the conditions as stated are met. But NOT as setup to spray a car, and that is what I was alluding to.

  20. #20
    Commander
    Join Date
    Jun 2011
    Location
    Middle Georgia
    Posts
    2,027

    Default Re: How do I gel coat my hull?

    Quote Originally Posted by zool View Post
    "You can't use an automotive sprayer for gelcoat"

    Well, he can per say...but only if his hvlp gun accepts a big tip,like 2.0+...2.5 would be best, and if hes fast enough to clean it between each fill before the thinned gel kicks......A cheap resin/gel spray gun would work better...
    Yes it would have to be at the very very least a 2.0mm tipped HVLP gravity spray gun or a better gun would even be a 3.0mm tipped. But even with that, I'm sure the pressure would have to be increased as well. Usually an automotive HVLP spray gun is 1.3mm and needs around 35 PSI going into the gun so you have the 10 PSI on the tip (OSHA demanded in pro shops). But with such a high viscosity medium like Gel Coat, it would probably splatter out of the gun instead of atomizing like normal automotive paints are sprayed. And if you want to keep that spray gun, it would have to be immediately disassembled and cleaned promptly too...or it will be a throw-a-way... Since the do make such quality epoxy and catalyst paints of every shade imaginable, I would seriously consider going that route. But it is your boat and it can be done and will yield a nice finish if done correctly... just my 2 cents worth...

  21. #21
    Cadet
    Join Date
    Apr 2013
    Location
    Toronto
    Posts
    11

    Default Re: How do I gel coat my hull?

    So i sanded down the hull. and after looking at it, its not as bad as i thought, i applied gel coat with roller and brush only on bad scratched and cracked areas. So now i will wait till tomorrow and sand it down again, and apply gel coat to the whole hull using a roller, its not that bad using a roller, gel coat goes on nicely, but i agree on its not like paint. then sand it down a little again, And i decided to use bottom side Anti-fouling marine paint, i will post more pics soon. and let you know how it comes out,

  22. #22
    Supreme Mariner Woodonglass's Avatar
    Join Date
    Dec 2009
    Location
    Broken Arrow, Oklahoma
    Posts
    15,622

    Default Re: How do I gel coat my hull?

    Huh??? R U Gelcoating or Painting?? What kind of Gelcoat are you rolling on? What Grade of sandpaper are you sanding with? R U getting a lot of Orange Peel? Did you Wipe down with Acetone prior to the first coat of Gelcoat? How long did you wait until applying the 2nd coat of Gelcoat? What did you do after you sanded the first coat?

  23. #23
    Lieutenant Junior Grade zool's Avatar
    Join Date
    Aug 2012
    Location
    NJ
    Posts
    1,219

    Default Re: How do I gel coat my hull?

    It looks like you're gonna lose that boot stripe with the antifoul, or at least go over it on the rear portion, which looks even worse...you only need antifoul if you leave in salt for prolonged periods of time. You may try floating it 1st and marking the water line to get a cut edge as close to the water line as possible. Post some pics when its done..Good Luck.
    "We all come from the sea. But we are not all of the sea. Those of us who are, we children of the tides, must return to it again and again."

    Current Boats
    10' tin gamefisher/Johnson 7.5hp ob
    1991 Sea Ray 170br/AlphaMerc
    1996 Century 1800 CC/Yamaha c85
    1988 Imperial 280SF (under the knife)

    http://forums.iboats.com/boat-restor...cs-598307.html

  24. #24
    Cadet
    Join Date
    Apr 2013
    Location
    Toronto
    Posts
    11

    Default Re: How do I gel coat my hull?

    IMG_20130417_192232.jpgIMG_20130417_192330.jpgIMG_20130417_192604.jpgIMG_20130417_192618.jpgIMG_20130417_193436.jpg
    Hi
    here are some pics, sorry again with my cell phone, the gel coat that i rolled on with a foam roller, did a not bad job, i filled in all the deep scratch and cracks using a brush, i opened up the crack a little using a pointy can open then sanded again, then i wiped down the whole hull with acetone then hot water and let it dry completely, then i applied gel coat to scratches and cracks, i will let it dry until tomorrow, then again re sand the hull until all scratches and cracks are even with hull body, then wipe down with acetone and fully roll gel coat over hull, after that i will sand hull again with 200 grit paper and paint hull with bottom side antifoul paint, i was told to get the antifoul paint from the marina its the same price $40 bucks a quart, which is all i need. You can see in the pics where i applied gel coat (it looks wet), it does have a little orange peel look but not really bad, i think after i apply gel coat to whole hull and sand it down again so paint can stick to it, it will look better. i will add more pics after i gel coat hull. Also Zool i have measured from top rails where water line is, and mark it down, Thanks.... Can i paint the whole hull with bottom paint? If theres any other info you can add please do, or if i'm doing something wrong,

  25. #25
    Lieutenant Junior Grade zool's Avatar
    Join Date
    Aug 2012
    Location
    NJ
    Posts
    1,219

    Default Re: How do I gel coat my hull?

    "Can i paint the whole hull with bottom paint? "

    Umm..you CAN do anything you want with YOUR boat....that said, you will get zero benefit from using antifoul above the water line, and the appearance will suck....Understand there types of antifoul (bottom paint). Ablative and Non...One wears off on its own, the other not so much...most antifoul is also formulated to activate in water, so you should generally paint it just before launch. Pettit makes a white antifoul (Vivid ) that kinda shines and has a harder shell finish, as opposed to the chalky finish you will get. But dont put it on the rest of the boat....As far as your technic, Woodonglass, and some of the other guys above are the ones to ask...Im sure ill be asking them glassing questions, when i get there lol..

    Looks ok from here so far tho....in the end, you're the only one that needs pleasing..
    "We all come from the sea. But we are not all of the sea. Those of us who are, we children of the tides, must return to it again and again."

    Current Boats
    10' tin gamefisher/Johnson 7.5hp ob
    1991 Sea Ray 170br/AlphaMerc
    1996 Century 1800 CC/Yamaha c85
    1988 Imperial 280SF (under the knife)

    http://forums.iboats.com/boat-restor...cs-598307.html

Page 1 of 2 1 2 LastLast

Similar Threads

  1. Blisters in hull gel coat. How do I fix?
    By Greg68S in forum Boat Restoration, Building, and Hull Repair
    Replies: 21
    Last Post: October 5th, 2012, 12:32 PM
  2. What to do with the hull now: Gel Coat Question?
    By Mostly Harmless in forum Boat Restoration, Building, and Hull Repair
    Replies: 0
    Last Post: June 9th, 2010, 10:55 AM
  3. Damaged hull gel coat
    By Wallman67 in forum Boat Restoration, Building, and Hull Repair
    Replies: 5
    Last Post: March 11th, 2010, 06:53 PM
  4. gel coat on the lower hull
    By Deimus in forum Boat Restoration, Building, and Hull Repair
    Replies: 5
    Last Post: December 9th, 2006, 01:40 PM
  5. Cracking Gel Coat in New Hull
    By Saberkitty04 in forum Boat Restoration, Building, and Hull Repair
    Replies: 3
    Last Post: August 15th, 2006, 11:24 AM

Tags for this Thread

  1. iboats Forum Directory - Over 100,000 forum posts organized by topic