Polyester resin catalyst chart. Good for repairing all boat surfaces.

Polyester resin catalyst chart With most unsaturated polyesters it gives longer gel and gel to cure times but with a higher peak exotherm than Norox® MEKP-9, particularly in thick sections. The catalyst agent creates a chemical reaction that allows the resin to change from a liquid to a solid state. mekp (methyl ethyl ketone peroxide) is a catalyst used in the composites industry for polyester and vinyl ester resins and gel coats. Catalyst Chart for polyester resin, gel coat and vinyl ester marine resins. MEKP Catalyst Quantity Chart CATALYST LARGE QUANTITY CHART CATALYST SMALL QUANTITY CHART All PRO-SET® High-Temp and Tooling Epoxies HTP-180 High-Temp Infusion Resin HTP-280 High-Temp Infusion Hardener HTP-182 High-Temp Laminating Resin HTP-284 High-Temp Fast Laminating Hardener HTP-286 High-Temp Slow Laminating Hardener HTP-187 High-Temp Surface Coat Resin To manipulate the working time and cure rate in your favor, you can adjust the amount of MEKP by adding less catalyst in warmer temperature conditions (more working time, slower cure), and more catalyst in cooler conditions (less working time, faster cure). It thins the resin or gel coat. THE RATIO IS APPROXIMATELY ONE OUNCE OF HARDENER PER GALLON OF RESIN. pdf), Text File (. Fiberglass laminating & repair or resin casting gel times will To catalyze TotalBoat Polyester Laminating Resin, at 77°F, add 7-8 drops of MEKP catalyst per one fluid ounce of resin. Please consult the Technical data sheet for your particular Resin before use, the above chart is merely a general guide to cover most general purpose resins. It has many applications and is notable cheaper and easier to use than other resin systems. Boatyard Polyester Resin is a non-spec resin that contains different types of polyester resins. Mix the polyester resin with a catalyst named methyl ethyl ketone peroxide (MEKP) to begin curing. As the catalyst mixes with the resin, a chemical reaction occurs, creating heat which cures (hardens) the resin. General purpose MEKP (methyl ethyl ketone peroxide) catalyst suitable for use with most polyester and vinylester resins and gelcoats. Adding the Catalyst: - For the appropriate catalyst quantity, refer to our MEKP Catalyzation Chart. Catalyst chart for polyester resin, gel coat and vinyl ester marine resins. txt) or view presentation slides online. And epoxy resins are measured by volume. vinyl ester and gel coats. Stir gently to avoid introducing air bubbles. All Fiber-Tek gelcoats are isophthalic resin based and are a brushing viscosity. When resin is curing it become hot as it goes through This document provides a chart showing the volume of methyl ethyl ketone peroxide catalyst needed in percentages from 1% to 1. Greenlight Polyester Resin Additive Chart - Free download as PDF File (. Perfect for boat owners and DIY enthusiasts using polyester. A epoxy resin is the most expensive of these. Confirm that both the resin and Pro Catalyst com- ponents are within “use-by” dates. 4. There is a note at the bottom to use 1/2 the recommended amount for temperatures above 90F. Trojan Fibreglass uses two methods for mixing ratios, all polyester and vinylester resins are measured by weight. Note the size and temperature variables. By balancing catalysts, inhibitors and initiators, manufacturers can change or control a resin’s cure profile in terms of shelf life, pot life, gel time, cure temperature and viscosity. 2% MEKP based on the weight of the resin). There are two main types of polyester resin: saturated and unsaturated polyester resin. 5 - 3%. 0-2. . Polynt A 4380-F Unsaturated Isophthalic Polyester Resin POSTER - Catalyst Chart (1-Quart Application) Catalyst Chart (1-Quart Application) POSTER POSTER - IMEDGE Mixing Procedure Imedge® POSTER - IMEDGE Mixing Procedure POSTER - Replacement of Scales POSTER - Replacement of Scales PRD-1586 PRD-1586 Polynt Reactive Deposition Thermoset 3D Print Learn the step-by-step process of shaping your own surfboard with expert tips and techniques. Measure catalyst accurately and stir thoroughly into Resin, wearing appropriate PPE. 75% (1 2/3 ounce to 2 1/3 ounces per gallon). Due to this mixing, MEKP can Aug 27, 2023 · A resin to catalyst ratio calculator is a specialized computational tool designed for determining the precise proportion of resin to catalyst in a mixture. 5%catalyst. K. How to measure and mix epoxy and polyester resins, how much resin to fiberglass a board, surfboard finbox install directions May 19, 2022 · Our polyester resin has an impeccable viscosity balance, effortlessly saturating surfaces to expedite the process and add no unwarranted delays with wetting out fiberglass While the initial reaction might exude a pungent odor (like all resins), rest assured that post-curing, the resin stands odorless. Catalyst is added to the resin at a rate of about one percent (1%), or approximately one ounce per gallon. Peroxide (MEKP) to catalyze polyester resin, vinyl ester resin and gelcoat. Find the optimal amount of M. DIRECTIONS FOR POLYESTER HARDENER POLYESTER RESIN/GELCOAT IS CATALYZED WITH MEKP (METHYL ETHYL KETONE PEROXIDE). Polyester resins are commonly used with fiberglass and sometime mistakenly called The table below contains the catalyst chart when using MEKP to catalyze Polyester Resins & Gelcoats. Catalyst for polyester and vinyl ester resins including gel coats. If you want consistent repeatable results when using polyester resin systems you need to measure your catalyst and I don't mean counting drops! Use a graduated bucket to measure your resin and Oct 6, 2022 · Fiberglass and resin are two popular materials used by boat builders, car restorers and other fiberglass enthusiasts. Since these compounds are unstable in their pure form, they are mixed with inert compounds to form the catalysts used in the industry. Typically added at 0. polyester resin is an excellent matrix material in the creation of fibreglass (grp) in the presence of a catalyst Catalysts,Promoters and Inhibitors Catalysts,also referred to as initiators,are organic peroxides that work together with promoters to initiate the chemical reaction that causes a resin to gel and harden. Includes potential pitfalls and limitations of using polyester casting resin. Contact SCOTT BADER COMPANY LIMITED Wollaston Wellingborough Northamptonshire NN29 7RL (For SatNav use NN29 7RJ) Telephone: +44 (0)1933 663100 Email: enquiries@scottbader. A polyester surface coat providing a cosmetic enhancement and exposure improvements to a fiberglass laminate. The hardener used with polyester resin is also called a catalyst. Mixing instructions are included on the can or One Gallon Polyester Resin = 9. Oct 10, 2023 · Styrene Monomer Styrene monomer is added to polyester and vinyl ester resins or gelcoat to give it better flow while spraying with a gel coat spray gun or paint spray gun. This article provides an in TotalBoat Polyester Laminating Resin requires the adding of MEKP catalyst at the ratio of 7-8 drops of MEKP per one ounce of resin at 77°F (1. Jul 25, 2025 · Unsaturated polyester resin (UPR) is one of the most widely used resins across various industries—from fiberglass production and marine components to mold-making, artificial stone manufacturing, and even crafts and decorative arts. This resin requires wax for the final coat to be able to buff and polish the board. This last coat is what is called t What is Polyester Resin? Polyester resins are unsaturated synthetic resins formed by the reaction of dibasic organic acids and polyhydric alcohols. e. - Slowly add the MEKP catalyst to the resin. NOROX® MEKP-9 gives consistent room temperature performance with both resins and gelcoats. Ensure MEKP (Methyl Ethyl Ketone Peroxide) is the catalyst added to polyester resins and vinyl ester resins. The calculator will evaluate and display the Resin to Catalyst Ratio. " Methyl Ethyl Ketone Peroxide (MEKP) is the chemical hardener used with polyester resin. However, there are a few common mistakes that people make when working with fiberglass and resin. It is not recommended to wet out fiberglass over 1/8” in thickness The Catalyst for Polyester Resin is (MEKP) Methyl Ethyl Ketone Peroxide. Oct 23, 2023 · 5 things you need to know before using polyester casting resin. MEKP (Methyl Ethyl Ketone Peroxide) Purpose: Acts as a catalyst to cure polyester and vinyl ester resins. Heat may be applied to accelerate cure time. CATALYST LARGE QUANTITY CHART Catalyst Concentration Resin Quantity Quart Gallon 5 Gallon 1/2% 1/16 oz 2/3 oz 3 1/3 oz 3/4% 1/4 oz 1 oz 5 oz 1% 1/3 oz 1 1/3 oz 6 2/3 To catalyze TotalBoat Polyester Laminating Resin, at 77°F, add 7-8 drops of MEKP catalyst per one fluid ounce of resin. 25% 1. This standard reactivity MEKP is the catalyst (hardener) used for all Easy Composites polyester and vinylester resin systems. Mixing: - Mix the resin and catalyst thoroughly ensuring a homogenous blend without any streaks or undissolved catalyst. Jul 31, 2023 · Enter the total amount of resin and the total amount of catalyst into the Resin to Catalyst Ratio Calculator. This guide provi Oct 22, 2024 · ISO tooling/laminating resin is promoted to gel in 17-23 minutes at 77°F when catalyzed at 1 percent (approx. [1] Synthetic resin is an industrially produced, typically viscous substance that converts into rigid polymers by the process of curing. Clear Catalyst Norox MEKP 925 Offered in multiple sizes, Norox® MEKP 925 is a methyl ethyl ketone peroxide composition formulated to be an excellent cure initiator for both unsaturated polyester resins and vinyl ester resins. The amount of time from which the catalyst is added until the resin begins to gel is referred to as the “gel time”. Try for FREE! MEK, short for MEKP, is the “Hardener” or catalyst for Polyester Resin and Vinylester Resin Systems including Isothalic and Gelcoat. Measurement: Accurate measurement is crucial for proper curing. When combined with its essential partner, MEKP (Methyl Ethyl Ketone Peroxide) catalyst, it cures into a hard, resilient plastic. E. To add styrene monomer, mix it thoroughly into the resin or gelcoat before the MEKP catalyst. Quarts and Gallons include the MEKP catalyst. com What is Polyester Resin Topcoat? Polyester resin topcoat – also referred to as flowcoat – is an excellent matrix material in the Applied to fibreglass (GRP) laminate in the presence of a catalyst, its purpose is to provide an additional layer of protection as well as offering aesthetic improvement via pigmentation. Jun 1, 2025 · Polyester resin is a versatile and durable material widely used in a variety of projects, from boat repair and fiberglass lamination to creating waterproof coatings for wood. Air temperature, humidity and shade or direct sunlight will be also be important to the gel time of the fiberglass laminate. This article will provide a detailed introduction to the manufacturing methods of polyester resin, including raw material preparation, esterification reaction, condensation reaction, post Silmar 249A is a resin used in surfboard building. P Catalyst for Curing. *For Drum Quantities - please contact us via our Contact Us page. Heat is what causes the resin to cure. Fiberglass Supply Catalyst Container, 300 Drops = 10cc. About methyl ethyl ketone peroxide (MEKP) MEKP is a catalyst used in the composites industry for polyester and vinyl ester resins. Use approximately 1/2 oz per quart of resin. Estimating Quantities Based upon Medium reactivity catalyst Butanox M50. It is a low viscosity resin generally used for laminating cloth to build a surfboard. MEKP is an organic peroxide. Nov 11, 2025 · Learn how MEKP catalyst works in polyester resin systems, including ideal mixing ratios, temperature tips, and safety practices to ensure strong, professional results. -Mix resin and hardener thoroughly. Available to buy online in 25ml, 125ml, 250ml and 500ml kits. Epoxy resins can be measured by weight, but due to the nature of specific gravity of the resin it is important to follow the ratio guide, and the use of electronic scales is essential. Bottle, Catalyst, (Methyl Ethyl Ketone Peroxide) MEKP Norox 925H initiator for polyester and vinylester resins, normally added to resin at a rate between 1-3% see resin instructions for details. The typical ratio is 1-2% MEKP by weight of the gelcoat. The ideal temperature for use of this product is 77° F. 5. You can find our MEKP catalyst quantity chart HERE. They are formed by the reaction of dibasic organic acids and polyhydric alcohols. Do’s and Don’ts 1. I set out to find the answer and found some websites seem to use volume and others use weight. When initiators & catalysts are mixed with resin, a chemical reaction occurs, creating heat that cures the resin. Only catalyze slightly more than needed. Ensure proper curing with ChemCalc's free MEKP calculator. Depending on the amount of resin needed, pour the appropriate ratios of polyester resin and MEKP into a heavy-duty plastic tub or bucket. 2. It's often used in hobby and DIY projects because it's relatively inexpensive and easy to work with. Catalyst and promoter levels can be adjusted,to a certain extent,to May 21, 2021 · I'm looking at the instructions for TotalBoat Laminating resin and it says mix 7/8 drops of catalyst per ounce (or 1 teaspoon) of resin. Ideal for repairing hulls, decks, cabins, and tanks. A Catalyst dispenser is ideally required for accurate A Guide for Catalyst Levels The amount of catalyst added to the resin determines how hot the reaction gets. Methyl ethyl ketone peroxide (MEKP) is an organic peroxide used in the marine industry. MEKP? More like I'm pouring resin on both pieces I'm laminating, then all the resin in the mixing cup falls out in one piece and everything goes hard. Fiberglass Resin Kit Our General Purpose Fiberglass Resin Kit offers improved anti-sagging qualities, fast wet out capabilities and is an economical option for repairs and construction for both above and below the water line. Typically used between 1. Unlike the polyester and vinyl ester resins, cured with a small amount of catalyst, epoxy resins usually require a lot more, often 1:1 or 2:1. It includes a catalyst addition chart showing the recommended percentage of catalyst to add based on temperature, resin to fibreglass ratio guidelines for different fibreglass materials, and an example calculation for estimating the materials needed for a 3 square meter project NOROX MEKP-9 is a methyl ethyl ketone peroxide in phlegmatiser for the curing of unsaturated polyester resins at ambient temperature in combination with cobalt accelerators. This presentation will intentionally focus on the unsaturated given its significantly greater range of Jun 1, 2015 · Here is the chart we came up with to help you determine both the suggested amount of resin for laminations, hotcoats, and gloss coats in epoxy and polyester resins; as well as the least amount of resin you can use on a surfboard (when you get as good as Davey at glassing surfboards) Requires M. Role of Catalyst: In composites, a catalyst is used to initiate and accelerate the curing or hardening of the resin system. Epoxy Resin: Epoxy resins are cured with the addition of a hardener. NOROX® MEKP-9 is a reliable product of remarkable purity and is available globally. Introduction Polyester resin is a synthetic resin widely used in the field of chemical production, with excellent physical properties and chemical stability. For polyester Gelcoats used in a moulding situation, we recommend from 2% to 2. In this video I show you how to Vinyl ester resin is an example of a synthetic resin. I just don't get the FGCI Polyester Filler Our Polyester Filler, Super Poly Fill, is designed with high quality materials composite finishes in mind. Add pre-measured Pro Catalyst Liquid via cup or tablespoon to the pre-measured resin com- ponent and stir for a full two minutes using a slow- speed spiral mixer (or a mixing stick for small batch quantities). Dive into the world of surfboard design and construction with Greenlight Surf Co. 2 oz. Mix thoroughly for at least one minute and apply immediately after. 5% 1. Thoroughly mix the entire pail of uncatalyzed resin before adding Pro Catalyst Liquid. MEKP is a free radical initiator that triggers the polymerization reaction in polyester and vinyl ester resins, leading to the formation of a solid and durable composite material. How It Works: When mixed with resin, MEKP initiates a chemical reaction that generates heat, causing the resin to solidify. It is mixed with MEKP catalyst to harden. MEKP acts as a catalyst to initiate the curing process of the polyester resin in gelcoat, allowing it to harden and form a durable, protective layer on surfaces like boats, cars, and fiberglass structures. Aug 29, 2023 · 4. Totalboat says its based on weight. Available in 8 lb size by phone Have you ever spent what seems like days measuring drops of mekp or catalyst for your polyester resin? We have all done it in a pinch, but there's a quicker way. In cool weather (55-60F) catalyze resins in the mid to high range: 301, 301W, 302, 303 & 305 resins at 10-15cc per quart, 40-60cc per gallon ISO Gelcoats at 15-20cc per quart, 60-80cc per gallon What is Polyester Resin? Polyester resin is an excellent matrix material in the creation of fibreglass (GRP) in the presence of a catalyst and combined with glass fibre chopped strand matting (CSM). Color may slightly differ between batches. Historical Background The use of Calculate the precise amount of MEKP catalyst needed for polyester resin or gelcoat based on volume and temperature. With most unsaturated polyesters it gives longer gel and gel to cure times but with a higher peak exotherm than Norox® MEKP 9, particularly in thick sections. In order to undergo curing, resins typically contain reactive groups, [2] such as acrylates or epoxides. This ratio affects the material's strength, durability, and cure time, making it crucial for applications ranging from simple DIY projects to complex manufacturing. Catalyst Chart Volume of Catalyst to Be Used with Polyester Resins Methyl Ethyl Ketone Peroxide-Percent by Weight 1% 1. Use the MEKP Catalyst Dispenser for precise dispensing. temp vs. Some synthetic Our polyester resin is a Iso blend resin, this is a perfect no-run, no-sag resin for marine repairs and boat construction. Resin that cures still in the mixing pot is unusable. Good for repairing all boat surfaces. It lists the amount needed in drops, cubic centimeters, and ounces for resin volumes ranging from 4 ounces to 5 quarts. This transformation is referred to as "curing" or "polymerization. May 30, 2009 · Re: Chart for poly resin cure times vs. 3. 75% Resin(1) Volume Drop cc oz Drop cc oz Drop cc oz Drop cc oz 4 ounce 32 1-1/4 1/32 40 1-1/2 3/64 48 1-3/4 1/16 56 2 1/16+. The Neutral gelcoat has no color pigments added but with the addition of the Coast Fiber-T Initiator or Catalyst Product Guide Video from Fiberglass Supply. CLEAR COTE CATALYST CONCENTRATION CHART How much catalyst to use will vary according to the type of work you are doing (fiberglass laminating or resin casting) and how long you will be working on the project. 75% when using it with polyester resins in various volumes. This tool aids professionals and hobbyists alike, ensuring the stability and durability of the resulting material, especially when used in molding and casting applications. Calculate accurate resin to catalyst ratios with our calculator, ensuring precise chemical reactions and optimal material properties. TAKE NOTE: For faster cure times, a “Maximum Catalyst” of 3% is recommended; catalyzation over 3%, “A Hot Mix” will affect Gelcoat color stability. The Catalyst for Polyester Resin is (MEKP) Methyl Ethyl Ketone Peroxide. For Darker Colors – use 2% MEKp Can I apply more gelcoat over uncured gelcoat As with all Resins, the pot-life/working time will vary significantly depending on the ambient temperature, the starting temperature of the resin, the amount of resin mixed and the catalyst ratio used. The MEKP Catalyst must be used or the resin or gelcoat will not cure. MEK, short for MEKP, is the “Hardener” or catalyst for Polyester Resin and Vinylester Resin Systems including Isothalic and Gelcoat. 13 Drop from 1 oz. Best for above the water line structural fixes like center consoles hatches, decking, boxes and more! Comes with the required MEK 925 catalyst. Nov 11, 2025 · Pro Tip 1 mL = 1 cc If using wood mixing stick, place stick in resin before adding catalyst so the wood doesn’t absorb catalyst. We recommend the use of our MEKP Catalyst Dispenser for accurate measuring and pouring of the catalyst. In this video we explain how to add catalyst to polyester resin for fiberglass repair or building new parts. 6. Air temperature and resin temperature greatly influence resin pot life, gel time and cure time. Unwaxed General Purpose Polyester Resin is mixed with MEKP catalyst to apply fibreglass and bond other composite materials. Initiator is used with polyeste resinsr, vinyl-ester resins, and gelcoats to initiate the chemical reaction that causes them to Polyester Resin Hardener Chart. Polyester Resin MEKP Catalyst (Methyl Ethyl Ketone Peroxide) Polyester (PE) resin hardener additive to cure Silmar 2880 (249B) Laminating Resin and 250B Hotcoat/Sanding Resin. USE THE FOLLOWING RATIOS FOR SMALLER AMOUNTS. Jul 7, 2018 · Mekp to resin chart difference Discussion in ' Fiberglass and Composite Boat Building ' started by Cjmac, Jul 7, 2018. 1% for summer (to give maximum wetting time) and 2% for winter. Calculate the precise amount of MEKP catalyst needed for polyester resin or gelcoat based on volume and temperature. MEKP, or Methyl Ethyl Ketone Peroxide, is a clear catalyst (hardener) added to gelcoat, polyester resin, and vinylester resins. Jan 1, 2023 · PDF | On Jan 1, 2023, Mohamed Farsane and others published Unsaturated polyester resins: Catalysts, accelerators, and inhibitors | Find, read and cite all the research you need on ResearchGate This document provides guidelines for estimating resin and catalyst quantities for fibreglass laminating projects. This document provides recommendations for using different types and amounts of catalyst additives when applying polyester resin coatings. MEKP (also known as methyl ethyl ketone peroxide) is a clear catalyst or hardener for the room temperature cure of unsaturated polyester and vinyl ester resins. Make adjustments to air temperature as noted on the resin container. 2 pounds Specific Gravity MEKP = 1. You can measure the fluid ounce (s) of resin in a clean mixing cup. Unwaxed polyester remains tacky after it has completed its cure so that more layers of polyester can be applied without having to sand or acetone wipe to remove wax. Polyester resins catalysed with MIBK peroxide have very long gel times at room temperature with rapid cure above 60°C, so this catalyst is generally used in the temperature range 60-120°C. Oct 3, 2024 · In crafting and industrial processes, the Resin to Catalyst Ratio (RCR) is essential for ensuring the proper chemical reaction and curing properties of composite materials, such as epoxy resins. Surfboard building tips and tricks. Best results for this product can be obtained at temperatures between 70° F and 85° F, in a clean, dry, dust-free environment. Check out out MEKP chart on the next slide to Resin 1kg We usually express this in terms of percentage ie:1% catalyst to resin = 10ml of catalyst to 1kg of resin. It can be added up to 8% by weight of the resin. It seemed like the stuff in the can got hard faster than what I had already poured. -Apply immediately to fiberglass or surface using brushes, fiberglass rollers, spreaders or squeegees. 25% and 1. May 22, 2024 · The manufacturing method of polyester resin 1. Norox® MEKP-925 RED is a methyl ethyl ketone peroxide composition formulated to be an excellent cure initiator for both unsaturated polyester resins and vinyl ester resins. Application: Sep 3, 2024 · What is the role of MEKP in gelcoat applications? MEKP acts as a catalyst to initiate the curing process of the polyester resin in gelcoat, allowing it to harden and form a durable, protective layer on surfaces like boats, cars, and fiberglass structures. Refer to the resin container or to the more detailed chart below to determine how much catalyst is required for the batch size you wish to catalyze. Add wax solution to make hotcoat resin. A rule of thumb for polyester laminating resin is between 1% and 2% i. Iso resin is more flexible and waterproof then your traditional 100% polyester resin. Adding MEKP causes a reaction that cures resin at room temperature. Below are two FREE MEKP Calculators and a MEKP CHART to simplify the process of determining the proper ratio of resin to catalyst or gelcoat to catalyst. Learn how to use MEKP catalyst with polyester and vinyl ester resins for fiberglass repair or construction. A caution note at the bottom warns of the explosive decomposition risk of organic The polyester resin catalyst chart amounts are for room temperature (70 degrees F). MEKP Chart and Calculators. 1 tsp per pint). One of the key success factors in using polyester resin lies in its correct and precise mixing ratio with the hardener (catalyst). It reacts with the resin to turn it from a liquid to a solid (cure it). May 16, 2019 · Nice chart but its significantly eaiser to use the metric system: 100cc polyester resin to 1cc hardener for 1%, for use in higher temps or for a slow kick @ complicated layups. The chart shows the percent by weight, volume and drops of MEKP for different resin types and quantities. For Pail orders, MEK needs to be ordered separately. bimvyh emf zgsq knab qors yaptpfux cryelw srzdll fion ttwr cwp nky blzdx fjagf yqcfs