What kind of sprayer neede for gel-coat?

Chuck B.

Cadet
Joined
Jan 26, 2002
Messages
23
Do you just use a suction type sprayer like you would use spraying automotive paint? Do you need to purchase different spraying heads for these guns? Or do they make a special spray gun for spraying gel-coat? Thanks for any help you can provide, Chuck B. :)
 

Hooty

Rear Admiral
Joined
Oct 2, 2001
Messages
4,496
Re: What kind of sprayer neede for gel-coat?

Chuck B,<br />You've got to use some sort of pressure spray rig for gelcoat.<br />You gotta mold and gonna build a fiberglass boat? That's tha only reason for spraying gelcoat ya know.<br /><br />c/6<br /><br />Hooty
 

mrm

Seaman
Joined
Apr 9, 2001
Messages
74
Re: What kind of sprayer neede for gel-coat?

Could you Add a clear-coat (gel-coat?) to the outside of your boat?? :eek:
 

Chuck B.

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Joined
Jan 26, 2002
Messages
23
Re: What kind of sprayer neede for gel-coat?

Purchased a fiberglass runabout w/ transom damage. It also has damage on the outside of the boat in the transom area. I have drilled out all rivets and seperated the deck from the hull, to get to all the damaged areas. When I finish all the repairs on the hull , I would like to re gel-coat it. I just need to know what type of gun I need to spray the gel-coat, or is this not the way to re-color the hull after repairing? Since the hull lacks its luster shine and is faded out, I thought I would spray the whole hull. The deck is white and is in good shape, but the hull is blue and badly faded. :)
 

petryshyn

Commander
Joined
Oct 3, 2001
Messages
2,851
Re: What kind of sprayer neede for gel-coat?

Yo chuck<br />I've never done it, but to my understanding, its going to go on like rock gaurd on a vehicle. Might want to do a search on gelcoat in this forum......<br /><br />good luck!
 

singerjr

Petty Officer 1st Class
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Jan 24, 2002
Messages
240
Re: What kind of sprayer neede for gel-coat?

I buy a lot of paint and if you're puttin your $$$'s out any mfg would be happy to supply any info you need to apply. Gun, PSI, nozzle w/needle ECT...<br /><br /> ;)
 

Hooty

Rear Admiral
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Oct 2, 2001
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4,496
Re: What kind of sprayer neede for gel-coat?

Gotta ask again, Chuck B., why gelcoat. After you spray it, you've got hours and hours of sanding and polishing to do. <br />Find yourself a good durable one part urethane paint, get all the dings,scratches etc. out, do a final sanding with wet 600 grit, wash it down good with soad and water, rinse good with water (notice no solvent or tack rag wipe) let it dry good and spray it with ah ever-day old suction cup spray gun. Don,t make something hard out of something relativily easy, and it'll look good.<br /><br />c/6<br /><br />Hooty
 

singerjr

Petty Officer 1st Class
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Jan 24, 2002
Messages
240
Re: What kind of sprayer neede for gel-coat?

Hooty,<br /><br />I use a lot of polyurethane but never gel coat. The cel coat looks fantastic from factory.<br /><br />Being so difficult to work with (reminds me of the old lacquers - sanding and polishing over and over to get that glass finish) Do the manufactures use it because it is far superior to anything else for fiberglass? Or is it like so many other paints these days an EPA reg for low VOC's.<br /><br />Our painters have had found the low VOC paints difficult to work with having to do a lot of polishing afterwards.<br /><br />Is gel coat a low VOC acrylic paint? In the past I've considered using it but didn't want to go to school on a small project.<br /><br />Thanks for your help :cool:
 

Terry H

Lieutenant Commander
Joined
Sep 25, 2001
Messages
1,862
Re: What kind of sprayer neede for gel-coat?

Chuck B...gelcoat is styrene resin with color tint and is used as the first coat in a mold. To paint a boat with this would be more work than it is worth. You would normally use to topcoat a small patch but not a complete paint job. Gel will not completely cure exposed to air, needs to be coated with a water solulable sealer to cure. I have topcoated with gelcoat on small one time projects when it is easier to sand and buff the item vs. making a mold. Gelcoat is just not intended to be used as a paint. I have to agree with the others about using a good polyurethane paint. <br />just a Thought
 
D

DJ

Guest
Re: What kind of sprayer neede for gel-coat?

Chuck B.<br /><br />Agree with everyone on the one part polyurethane. It will look good.<br /><br />If you really want to be trick and get that deep color look. I had a boat painted with an automotive, base coat/clear coat and it worked fine.
 

Hooty

Rear Admiral
Joined
Oct 2, 2001
Messages
4,496
Re: What kind of sprayer neede for gel-coat?

Gelcoat is polyester resin with pigments, fillers, thixitropic agents etc. The reason it looks so killer on your boat is the side you see is the side that was next to the mold. If the mold has a finish like glass, thats what the gelcoat you see looks like. The other side,like Schematic sez, looks like dull rock guard. Re-gelcoating is definitely not worth the effort and not as tough and durable as some of the paints out there.<br />djohns 19 has the right idea and if you put just a little pigment in that last coat and make in translucent, it'll look about three inches thick.<br /><br />c/6<br /><br />Hooty
 

captain bly

Recruit
Joined
Mar 1, 2002
Messages
5
Re: What kind of sprayer neede for gel-coat?

chuck b they call it a dump gun, they coat about i50.00 dollars. Go to yahoo search engine and type gel coat, it will bring you to some sites that sell them. one place is called min craft in florida, or minicraft not sure of correct spelling. good luck
 

speed29668

Seaman
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Apr 30, 2002
Messages
74
Re: What kind of sprayer neede for gel-coat?

I'm preparing to do the exact same thing. I've read in a widely available fiberglass book (can't remember the title off hand) that gelcoat is the superior coating, but the trade off is the time and effort. Gelcoat is based of polyester which is a kind of plastic. If you have a lot of time and have spent a good portion of it in preparation you may be on your way to success. I've corresponded with several manufacturers and a siphon feed or HVLP gun will work, but the amount of thinnning that will be required is based on the size of the tip on the gun. You have to spray the entire can out before it begins to gel. The last coat must have liquid wax mixed into or sprayed onto it to seal it off from air. This eliminates the tacky feeling. Definitely consider polyurethanes as a much easier, and most of the time a "just as good", alternative.
 

Mumblerone

Petty Officer 1st Class
Joined
May 12, 2002
Messages
344
Re: What kind of sprayer neede for gel-coat?

Take a look at www.uspaint.com they are the makers of Awlgrip...this is the standard for refinishing on boats. I personally believe your going the wrong way "gel coating" the whole boat. This is a factory type operation using polished molds! It's OK to repair gelcoat, however. Think more about it!
 

Tinman

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Joined
May 27, 2002
Messages
17
Re: What kind of sprayer neede for gel-coat?

I strongly second the polyurethane advise, fix your transome and topcoat with a high quality Poly, Studies have shown polyurethane to be even less porous than gelcoat/fiberglass alone. I have sprayed gel coat on some pretty big sections of boats and airplane parts, to anser your question, Yes, it can be sprayed with conventional suction type sprayguns, I prefer a gravity feed gun for smaller jobs and a pressure pot for larger stuff. It's a real PITA to work with, and you must use a surfacing agent to keep the waxy film from forming on the final coat(s) or it will next to impossible to to get a smooth glossy finish.<br /><br />note: the gelcoat info I just posted is for educational purposes, but for your project an epoxy primer and polyurethane topcoat is the best advise..be sure to wear a respirator, air supplied if possible (it's your lungs not mine)<br /><br /> http://www.westsystem.com/ there is ALOT to learn (and buy) at this site. excellent epoxy and other boat makin stuff.<br /><br />Tinman
 

ken P

Recruit
Joined
Jul 18, 2003
Messages
2
Re: What kind of sprayer neede for gel-coat?

Ive been repairing a 1984 tri-hull, that had a couple of holes and some major stress cracks in the hull,(we dropped it off of the trailer). After many partial repairs I decided to flip it over and repair the problems. The repairs have been made and several coats of one step paint with hardner have been put on. Im just not satisfied with the hardness of the finish. Im going to try to thin out the Bondo resin and spray it on. Any comments or sug. I read every thing on the forum and ask as many paint people I could find but still confused. Is the repair resin the same basic formula as original gel-coat sprayed into a mold?
 

snapperbait

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Joined
Aug 20, 2002
Messages
5,754
Re: What kind of sprayer neede for gel-coat?

Ken P. If you are not happy with the finish as it is, you will really be unhappy if you try to spray any type of resin or gelcoat over the painted surface... I doubt if the paint would withstand the heat generated from the resin or gelcoat without turning into toxic goo...<br /><br />Ok here goes... Gelcoat 101... <br /><br />To do a re-gelcoat job correctly, you would have to remove all the paint down to bare fiberglass before applying gelcoat... It can be sprayed with a "regular" spray gun with a large nozzle orifice like whats used to spray most high build primers.. The gelcoat (it's some thick stuff) must be thinned, usually with acetone... After the gelcoat is sprayed you must go back and spray PVA (poly vynal alcohol,sp?) over the entire surface to seal out any air... Some gelcoat has wax already in it which will do the same thing as the PVA, but if you can't spray the proper thickness (which is usually .15 - .20 thousandths of an inch) over the entire surface of the boat in one shot without the gelcoat kicking off, you would have to sand and remove all the wax before spraying any more gelcoat.... Gelcoat will only cure properly if the fresh surface is sealed off from the air/atmosphere, hence the need for the PVA or wax(styrene), which creates a "seal" between the outside air and the gelcots surface... ... If you don't use the wax or PVA, when you start to color/wet sand (and you will) the sandpaper will immedately clog up on you...<br /><br />Once the gelcoat has cured, the real fun begins... Sanding till your fingers bleed... :eek: Gelcoat is not self-leveling like most paint so it will be full of (at best) orangepeel which must be sanded out with progressively finer wet sandpaper before you can start buffing the surface out...<br /><br /> Bondo "repair" resin is no good to begin with let alone trying to thin it out and spray it... You would undoubtedly trash your boat doing this...<br /><br />Whatever you decide, I wish you good luck... :)
 

Link

Rear Admiral
Joined
Apr 13, 2003
Messages
4,221
Re: What kind of sprayer neede for gel-coat?

Hi Chuck<br /><br />Three words..<br /><br />polyurethane <br /><br />polyurethane <br /><br />polyurethane <br /><br />Or one of the other products mentioned above should work just fine also... but not the gelcoat.<br /><br />When I wanted to paint a little hot rod I went to our Gelcoat/fiberglass guy and ask him what to use. I told him I wanted it to be the brightest white there was.... In direct sunlight you could hardly look at it!<br />Becare and use proper protection because when I went to pick up my car he showed me where the over spray had went across some water and cured...he picked it up like any other plastic bag! And it will do the same in your lungs.. :( <br /><br />Someone else mentioned using clear coat.. I didn't on the outside because its easier to touch up when needed, but did on the zolatone on the inside and WOW it looks like it's a inch deep!<br />Here is another site on the product I used.. maily because we sold their stuff and I could buy it at cost! :) but might be worth reading <br /> http://www.fiberlay.com <br /><br />Luck to ya and let everyone know how it turned out<br />Link
 

Ralph 123

Captain
Joined
Jun 24, 2003
Messages
3,983
Re: What kind of sprayer neede for gel-coat?

Chuck, yoou're gonna be surprised but the best way to spray gel coat is with those little hobby sprayers like they use for model cars.<br /><br />Do your self a big favor and head over to Amazon and search for the tape "figerglass and gel coat repair" or something like that. Great tape which takes you through the entire process.
 
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