Pva spray for gelcoat. International Orange Gel Coat is a custom ISO NPG polyester gel coat color. Jun 11, 2019 · The purpose of the wax is to create a barrier between the gelcoat and the oxygen in the air so the gelcoat can fully cure. I posted earlier about paint coming off the original parts I used as the plug. CAN PVA BE APPLIED USING A BRUSH INSTEAD OF A SPRAY GUN? PVA can be applied using a brush, cloth, sponge or roller or the part may be dipped in the PVA and drained. I'm thinking about redoing the molds. PVA (Poly Vinyl Alcohol) Patch Sealer - Eliminates the tackiness from the spray patch by creating a seal from the oxygen. Once the gelcoat has cured, it doesn't matter when you remove PVA from the surface. To ensure a proper release of the mold, several thin coats of PVA, can be added. Jan 24, 2022 · I'm reading in a repair book about applying gelcoat. s Preval let you use your own paint. I think if I thinned the PVA just a little it would be usable. It is great for boat building, repairs, molds, spray up processes and hand lay up. 2. Part of the mold - a small spot of gelcoat - pulled away with the seat, so now that must be repaired. Waxed resin is typically not desired on first layers if there will be subsequent layers. This premium Fighting Lady Yellow gel coat is designed to give excellent protection against varying weather conditions and UV light while retaining high gloss and color. Available in Clear or Green. flush with WATER then flush with acetone. 25% Mek-P. Home Depot has them. this handy portable tool can spray all kinds of liquid solutions. ) Partall® Film #10 PVA Surfacing Agent For Gel Coat: Use this product as a surfacing agent when using Gel Coat without wax additives and typically larger spray applications. PVA Mold Release Agent for Gelcoats and Resins Polyvinyl Alcohol, or PVA is a mold release spray that is easy-to-use for all composite molds or epoxy projects. Cruisers & Sailing Forums > Engineering & Systems > Construction, Maintenance & Refit How to Cure Non-Waxed Polyester Gelcoat Nov 19, 2020 · Gelcoat (and polyester resins) will not fully cure until they are cut off from air. I also used a cheap plastic painters tarp to cover the entire ski to make sure nothing got hit with overspray. Thin with a small amount of acetone to allow for an even spray. I spray painted my Partall® Film #10 is a water/alcohol-based polyvinyl alcohol (PVA) mold release agent that forms a barrier between parts and mold surfaces that are still curing (green or recently reconditioned molds can be reactive). This water-based agent can also be applied to the inside of a mold to create a smooth film so composite parts can be removed Apr 19, 2016 · The gelcoat and MEKP hardener. May 16, 2006 · It's easier to use the surfacing solution than PVA and for most jobs the results are about the same. PVA is essentially a brush/spray on saran wrap - which cures the surface by depriving the surface of exposure to air - but it is easily washed off. You can spray it with polyvinyl alcohol (PVA) before gelcoat reaches its gel stage (5-10 min. Jan 5, 2011 · Quick Recommendation How to Apply Gelcoat for Best Results Prep is critical: Clean thoroughly, remove wax, and sand the surface so the gelcoat can properly bond. Mar 6, 2015 · Yes poly gel coat is OK over vinyl ester but you will need PVA (or a wax additive) over the gel coat. Sep 16, 2024 · bristol299bob said: I would test a sample with your wax at the same ratios, at temps recommended, to confirm you don't have a bad batch. 2 PreVal sprayers (Home Depot - < $5 each). Spray Guns can be used to effectively spray gel coat, PVA parting film, and a wide selection of primers. Ready to spray: Spray Guns can be used to effectively spray gel coat, PVA parting film, and a wide selection of primers. Tip: Gelcoat exposed to air will remain tacky—use a wax additive or PVA on the final coat to ensure a full cure. It may be applied over polyester repairs, or gel coat, as a surface layer for airless tack-free cure. ) Gelcoat without wax is commonly used for laminating gelcoat in stages, or when applied onto a waxed mold, where fiberglass (or another reinforcing fabric) saturated in polyester resin is laminated onto the unwaxed gelcoat. That is because both vinyl and poly are air inhibited - which means that they do not harden until air deprived. Sand and Buff the Repair: (The Gel coat may still be a little tacky. An alternative to that is to tape a piece of wax paper around the entire gelcoat repair so air doesn't get to it. Packaged in 1-gallon, 5-gallon and 55-gallon container sizes. Nov 18, 2013 · Getting to the point of applying your color matched gelcoat is one of the last steps in finishing off your repair (s). PVA Water Based Mould Release - Polyvinyl Alcohol Agent for Epoxy, Polyester, Vinyl Ester, Resin, Gel Coat, Polyurethane Foam, Silicone-Spray or Brush-On Film for Sculpture and DIY Projects Dec 30, 2025 · This article highlights five top PVA spray options designed for epoxy, polyester, vinyl ester, and gel coat applications, plus a practical buying guide to help you choose the right product for your molds and DIY projects. spray PVA . Use this product as a surfacing agent when using Gel Coat without wax additive. Forget trying to match colour swatches with pre-filled spray can. Do not apply more gelcoat yet: Uncured material must be removed or sealed correctly before Home How To & Tools Gel Coat Application Guide - How to apply gelcoat correctly Gel Coat Application Guide - How to apply gelcoat correctly Gelcoat is a resin system that is filled with colorants and thickening agents and applied to a mold surface to form the cosmetic and weathering coating of a composite part. I just spray it with a windex spritz bottle in a pinch. weather temp amount of hardner can change the end result . I pretty much understand that if I spray 2 layers (no wax) with the Preval sprayer, the third layer will have to be either gel coat that contains wax or a layer of gel coat, then PVA to seal it up so that it will harden. ) Jun 16, 2009 · The gel coat won’t cure when exposed to oxygen. Jun 19, 2012 · Just use polyvinyl alcohol (PVA) and spray it on the surface when done for a 'surface cure' of the gelcoat. Available in green or clear (water-white). Jan 31, 2005 · To deal with this, you can either add a wax surfacing agent (rises to the surface of the gelcoat once applied and seals it for curing) or you can spray PVA over the gelcoat. ca: Home About this item Coating: PVA can be applied as a thin film or coating onto the surface of a mold or other surface where sticking might occur. I was looking for possible suggestions and came across the raw granulated form. In the video I mentioned that there were 2 common ways to do this; spraying or brushing. Blue nitrile gloves (Harbor Freight); gelcoat is sticky. 5% to kick the gel coat in about 10 minutes. Apply in thin, controlled layers: Build thickness gradually rather than applying heavy coats. PVA should form a smooth, glossy surface that will not shrink or pull away from corners or curved surfaces. I'd also spray PVA on on the repair just to see if that will get it to cure. 3. Jan 27, 2005 · Spraying PVA over gelcoat is tricky, better to use waxed styrene or finish gelcoat for final coat? Polish with 400, 600 etc all the way to 1200 and then buff with fine rubbing compound? Gelcoat will not fully cure without adding a surfacing agent or wax additive sanding aid. Does anyone know of a reason to not roll gelcoat with wax? It seems gelcoat with wax Bottom line: Successful gelcoat application depends on proper surface prep, correct catalyst ratio, and controlled application. PVA is also known as 'parting fluid' or 'mold release' and causes a surface cure of the gel. The right PVA spray can simplify gelcoat and resin work by delivering effortless part release, clean surfaces, and efficient coverage. It was the worst case of fish eye I have ever seen. Gelcoat Spraying Questions - Moderated Discussion Areas Hop to: In this comprehensive tutorial, we show you how to spray gelcoat like a pro on a budget! Whether you're a DIY enthusiast or just looking to save some money o D. Note: The pattern is coated with green polyvinyl alcohol (PVA) to serve as a release agent as well as a barrier coat that prevents a chemical reaction that will occur between the Rubber Repair Non-Skid Pattern and gelcoat, resulting in a distorted pattern. Use a PreVal 'aerosol type' self-contained sprayer that you 'load' any (pre-filtered) fluid you want, including diluted down gelcoat. The resin will remain soft and sticky until the area is covered with wax or PVA. Depending on where you purchase the gelcoat, it may already have wax in it so read the product description carefully. Please specify the color and size you are inquiring about. Thanks. Item #126-A is a gravity fed HVLP-style gun that features a 2. Ready to spray: Jun 17, 2020 · Replacing your gelcoat with Durabak is the ideal preventative solution to avoid scratches and cracks to prolong the life of your marine craft. Oct 27, 2010 · You might just want to skip the wax and spray PVA over the gel when its tacked off. Brushed on the Evercoat PVA, and voila, the gelcoat cured. PVA may be used as a sealer to prevent tackiness to the final cure. BoatLIFE offers a number of high quality boat waxing products to ensure a properly-protected gelcoat for years to come. Barrier: Once applied, the PVA Dec 7, 2011 · It didn't work nearly as well as PVA. PVA Partall mold release film application guide. But the results are worth the trouble. If you use PVA, do it when it's still relatively wet, if you wait too long the gel coat will have already tried to crosslink with the air and may not cure as well on the surface. Maybe I can thin it with Iso alcohol or water? Jan 13, 2019 · Sprayed gel coat doesn't self level like auto paint. Jun 17, 2020 · Gelcoat may be thinned for use in a Portable Preval Sprayer with styrene monomer. You can add surface seal, PVA wax paper etc. PVA is short for polyvinyl alcohol. You can spray it with polyvinyl alcohol before the gelcoat reaches its gel stage or by adding around one ounce per quart of the wax additive. ) Jul 29, 2012 · Re: Gel coat still tacky after a few weeks? What are my options? Thanks Scott and ondarvr. Mar 23, 2015 · Allow the gelcoat time to kick before adding subsequent coats. This item: PVA Water Based Mold Release - Polyvinyl Alcohol Agent for Epoxy, Polyester, Vinyl Ester, Resin, Gel Coat, Polyurethane Foam, Silicone - Spray or Brush-On Film for Sculpture and DIY Projects - 8oz PVA Water Based Mold Release - Polyvinyl Alcohol Agent for Epoxy, Polyester, Vinyl Ester, Resin, Gel Coat, Polyurethane Foam, Silicone - Spray or Brush-On Film for Sculpture and DIY Projects - 8oz Brand: Uniproducts £1982 PVA Water Based Mould Release - Polyvinyl Alcohol Agent for Epoxy, Polyester, Vinyl Ester, Resin, Gel Coat, Polyurethane Foam, Silicone-Spray or Brush-On Film for Sculpture and DIY Projects 200+ bought in past month Add to cart Nov 18, 2013 · Getting to the point of applying your color matched gelcoat is one of the last steps in finishing off your repair (s). This guide highlights five top options, comparing their release performance, application flexibility, and coverage to help you choose a reliable PVA spray for gelcoat projects. In this video - I have a quick look at the application of Poly Vinyl Alcohol to create a barrier as part of a mold release system for making fiberglass molds Jan 13, 2019 · Sprayed gel coat doesn't self level like auto paint. How does one remove uncured gelcoat? - Moderated Discussion Areas Hop to: High quality Oyster White custom colored gel coat is great for boat building, new parts, repairs, molds, spray up processes and hand lay-up. Acetone, because I literally could not find Styrene. You get the perfect PVA (Poly Vinyl Alcohol) Patch Sealer - Eliminates the tackiness from the spray patch by creating a seal from the oxygen. Learn more It may seem like a dark art, but spraying Gel Coat is a simple process with some basic technique and maintenance your HLVP Spray gun can last for years and give you trouble free service. I started spraying on a very light coat at first and the result looked dry like chalk so I went heavier and heavier until it looked wet. Never seen gelcoat curdle. PVA Partall #10 resists the solvents in the polyester or epoxy resin system and is water soluble, making cleanup easy. So, the question is do you wax then PVA, or PVA then wax? Or just straight PVA or just wax? This piece was just wax and pulled gelcoat from the mold. Jul 25, 2025 · While gel coat can be applied by brush or roller, we strongly recommend the use of spray equipment. Question 1: The fact that the pot life of the gel coat with catalyst is between 5 and 15 Sep 9, 2009 · Re: gel coat tacky??how long to fully harden. Other products such as PVA (polyvinyl alcohol) can also be applied over gelcoat without wax to cure it. Preval does it all. I spray painted my Comments about PVA Polyester Curing Agent by Evercoat | Boat Maintenance at West Marine I had brushed on some waxed gelcoat, probably too thin, probably disturbed the wax layer trying to brush on more gelcoat, ended up with sticky, non curing mess in places. As such, you need to spray it with water soluble poly-vinyl-alcohol (PVA) to seal it from the air to allow it to harden. In the section about rolling it only mentions gelcoat without wax and goes on to point out the need to brush or spray on PVA afterward so the gelcoat cures. Apr 19, 2016 · The gelcoat and MEKP hardener. Not touching it til it dries but curious if anyone knows what I am up against. Spray from a distance that allows PVA to atomize (mist) completely before coming in contact with the gel coat. This will give you material to work with when you're sanding and polishing. Cruisers & Sailing Forums > Engineering & Systems > Construction, Maintenance & Refit How to Cure Non-Waxed Polyester Gelcoat Sep 9, 2009 · Re: gel coat tacky??how long to fully harden. ), or adding 1oz per quart of wax additive sanding aid. The catalyst to set off the reaction with the gel coat is methyl-ethyl-ketone-peroxide (MEKP). If you can't fine wax or PVA you can wipe the surface down with acetone to remove the sticky layer before sanding. (Essential for all types of Gelcoat repairs and so easy to use. Feb 25, 2026 · When working with gelcoat and composite resins, a reliable PVA spray creates a smooth, easy-release barrier between your part and mold. A capacity of 16 oz. Building the Mold Begin by spraying 2 coats of Tooling Gelcoat (LBI 304) at least 15-20 mils thick. When you’re done, spray it with a PVA curing agent. Nov 19, 2020 · Gelcoat (and polyester resins) will not fully cure until they are cut off from air. Final Steps & Post-Repair Wax Now you have the option to sand it down and peeling off the PVA to apply the wax. This is one of the questions Bottom Paint Store is asked the most. This item: PVA Water Based Mold Release - Polyvinyl Alcohol Agent for Epoxy, Polyester, Vinyl Ester, Resin, Gel Coat, Polyurethane Foam, Silicone - Spray or Brush-On Film for Sculpture and DIY Projects - 8oz. While these products can be applied with a brush or roller, we recommend they be sprayed on for several reasons: Superior quality finish—Spray Guns leave behind a smooth, uniform surface area or repair, free of the inconsistencies and brush strokes common with other methods of application Normal gelcoat should be catalyzed at around 1% – 1. It has a light orange peel finish that requires multiple steps of sanding before you reach gloss. Evercoat PVA (from Amazon). To save things I got out a rag and wiped the whole mess off. You can build up thickness of gelcoat without sanding between simply dont add the wax inbetween coats. Bottom line: Successful gelcoat application An alternative to using surfacing wax in the gelcoat mix is to over spray the gelcoat with PVA, (polyvinyl alchol). . Can I just give it an acetone wash, new layer of gel coat and spray the pva? It sounds to me that you are saying I will have better luck with the pva. It is acceptable to wipe off the tackiness with a cloth and acetone. Jun 17, 2020 · Replacing your gelcoat with Durabak is the ideal preventative solution to avoid scratches and cracks to prolong the life of your marine craft. Surfacing wax and special patch thinners are needed for the last coat. While these products can be applied with a brush or roller, we recommend they be sprayed on for several reasons: Superior quality finish—Spray Guns leave behind a smooth, uniform surface area or repair, free of the inconsistencies and brush strokes common with other methods of application Note: The pattern is coated with green polyvinyl alcohol (PVA) to serve as a release agent as well as a barrier coat that prevents a chemical reaction that will occur between the Rubber Repair Non-Skid Pattern and gelcoat, resulting in a distorted pattern. PVA is better than a wax additive Apr 4, 2011 · Gel Coat Repair Method Page 1 of 1 Page 1 of 1 Board index » Hobie Catamaran Sailing » Help with repairs All times are UTC [ DST ] Gelcoat without wax is commonly used for laminating gelcoat in stages, or when applied onto a waxed mold, where fiberglass (or another reinforcing fabric) saturated in polyester resin is laminated onto the unwaxed gelcoat. Sprays gelcoat, PVA and paint. then WATER. i sometimes spray gelcoat neat just with acetone to thin, then spray a coat of pva just after the gelcoat is on the verg of geling to block Mar 23, 2015 · Allow the gelcoat time to kick before adding subsequent coats. Let the gelcoat “gel” in between coats. Without Wax: Resin “without wax” cures tacky so there is no need for sanding between layers. You need about 1. I got the seat off the mold but it was more of a struggle than usual, and I think it was the wax that was doing the mold release job, not the hair spray. Partall Film #10 is a polyvinyl alcohol (PVA) water/alcohol solution of water-soluble, film-forming materials. What is the best gelcoat repair kit? Different kits are better suited to different types of boat repairs. Dec 10, 2021 · I'm not having good success with the PVA on these tests because it is too thick to apply with a spray bottle, and so I apply if with a 2" chip brush, and in applying it 8 minutes after I texture the gelcoat with the roller, the brush is smoothing out the PVA. PVA (polyvinyl alcohol) is sprayed on the surface of gelcoat without wax in order to make the gelcoat cure properly. Nov 1, 2005 · gelcoat takes a lot of practice and will be different every time. If you don't use gelcoat with wax, then you'll need to spray or brush on some PVA over the gelcoat after it sets up. Feb 5, 2012 · I decided to spray the PVA and what a terrible mess resulted. ), or add 1oz per quart of a wax additive sanding aid. 5mm nozzle, which is an excellent starting point for spraying gel coat. Made to Order. Waiting for new Polyester resin and gelcoat to arrive tomorrow. This guide highlights five top products that improve release performance, application efficiency, and finish quality. When the gelcoat has been applied, finish with an application of PVA as described earlier. You can spray with PVA before gel coal reaches its gel stage (5-10 min. Jan 19, 2023 · Mold release systems and how to use them: wax, PVA, sacrificial and semi-permanent, release films - surface preparation, application and troubleshooting. Description Polyvinyl Alcohol (PVA) Mold Release & Air Dry Agent is used as an air-barrier on top of catalyzed polyester resin without wax, catalyzed polyester gelcoat without wax, or catalyzed polyester structural putty without wax to allow a proper, tack-free cure. I am using a Prevail sprayer but it clogs up during use. Pot life is fairly short and HVLP gun cleaning must be extremely thorough, like tearing the front of the gun apart. PVA Water Based Mould Release - Polyvinyl Alcohol Agent For Epoxy | Polyester, Vinyl Ester, Resin, Gel Coat, Polyurethane Foam, Silicone-Spray Or Brush-On Film For Sculpture And DIY Projects Feb 2, 2010 · Re: Primer for Gelcoat? It won't cure or spray well at lower temps and depending on where you bought the gel coat they should also sell surface wax so it will cure correctly and not be tacky, its easier to use than PVA. You want the finished spray application to be thicker than the surrounding gelcoat. For an optimum surface cure spray PVA release film over the gel coat patch during the curing process. 1. Gelcoat may be thinned for use in a Portable Preval Sprayer with styrene monomer. The problem with this method is getting the right amount of material misted onto the un-cured gelcoat to block the air out and in gauging just when to apply the PVA. So my question is heat and mix a little hot water in it? Or maybe just heating Preval Sprayer Complete You can spray just about everything with the Preval Spray gun. Confirm curing conditions: Gelcoat requires proper temperature, humidity control, and oxygen exclusion to fully cure. Fighting Lady Yellow Exterior Gel Coat that is Premium Professional Grade with superior leveling, anti-sag, and color retention. I use PVA as a mold release after waxing, it will form a great barrier for your purpose. for Nov 11, 2025 · Quick Recommendation Gelcoat Did Not Cure: What to Do First Check the catalyst ratio immediately: Incomplete or incorrect MEKP mixing is the most common cause of uncured gelcoat. PVA is better than a wax additive Dec 25, 2008 · I bought an 8oz bottle of PVA to spray on gel coat. The PVA is a release agent that you can use as a surfacing agent when using gelcoat without the sanding aid. Jun 9, 2025 · RAYPLEX PVA Water Based Mold Release - Polyvinyl Alcohol Agent for Epoxy, Polyester, Vinyl Ester, Resin, Gel Coat, Polyurethane Foam, Silicone - Spray or Brush-On Film for Sculpture and DIY Projects - 1L : Amazon. Spray PVA onto the sprayed Gel coat approximately 15 minutes after applying the coat. Fibre Glast offers spray guns specifically for gel coat. It said that PVA would dissolve in HOT water but not Cold water. even the air presure on the gun can change the end color so csn wax and duratec. This means that the gelcoat will be tacky, but will not come off onto your finger when touched. WARNING WHEN USING PVA = clean your gun with acetone. Question 1: The fact that the pot life of the gel coat with catalyst is between 5 and 15 Jul 29, 2012 · Re: Gel coat still tacky after a few weeks? What are my options? Thanks Scott and ondarvr. The gelcoat will be sticky and uncurred, then add wax for final coat. Partall® Film #10 is a polyvinyl alcohol (PVA) water/alcohol solution of water-soluble, film-forming materials. As a dry film, PVA is resistant to the solvents in a resin system, but is water soluble. Have a large area of fiberglass boat gelcoat that needs to be repaired? Using a disposable Preval sprayer to repair boat gelcoat may be the best method for applying it. The finish will be dull and not smooth like paint-it doesn't level off or layout like paint does. Keeping a consistent distance from the repair area with each pass, apply an even layer of gelcoat to the sanded area then allow to dry for 15-20 minutes. Jun 17, 2020 · Gelcoat does not fully cure without first supplementing it with a surfacing agent or wax additive sanding aid. It is a water soluble material that can be used either as a release agent when applying gelcoat as a first layer into a mold, or to act as an air-inhibiting agent. Directions on how to apply Partall properly to your fiberglass molds. Preval is a big time saver for small paint jobs. This will allow it to fully cure. Ditto on the application of PolyVinyl Alcohol - PVA , Simply use PREVAL sprayers (about $6 each) to apply. Oct 24, 2011 · Then you spray either product, prime and paint, or thinned gelcoat. So I want to reapply a gel coat finish to the center console where I did some repairs. Also, when these products are mixed in, no PVA is required to achieve a full cure. Partall® Film #10 PVA Surfacing Agent For Gel Coat: Use this product as a surfacing agent when using Gel Coat without wax additives and typically larger spray applications. When using these additives, the overall mix needs to be catalyzed at 2% or higher (it will be stated on the product container). Gelcoat is a crucial component in boat maintenance, and knowing how to properly work with it can save you time and money in the long run. Mix gelcoat compound with hardener according to instructions, then pour the mixture into the Preval sprayer bottle. Alternatively, add a paraffin wax additive to catalyzed gelcoat without wax for the final layer in your layup so it cures and hardens properly. More Details To cure gelcoat without wax, brush on or spray P VA (polyvinyl alcohol) over the final layer. Mix and catalyze correctly: Measure MEKP accurately and mix completely to avoid curing problems. Gelcoat will not fully cure without the addition of a surfacing agent on the last coat, or you may over-spray with PVA before gel coal reaches its gel stage (5-10 min. hcnrl wmaesac luqbd xqypc xucjxpyp vkvdxq qwplwa zoxyx cmod tttfzzj