Conclusion. . For the Water Clear Casting Polyester Resin, this drops to 1.5% or 15ml for every 1kg. This additive contains paraffin and styrene. [3] 2. For example, four drops of hardener will be 1 percent of 1 ounce of resin. Not mixing your resin and hardener thoroughly, mix for at least three minutes and make sure to scrape around the sides and bottom of your container. Ratio. Mix the paint and thinner together. If you mix too much of component A, vs B, then when the chemical reaction occurs, there will be un reacted component A because it could not find enough component B to complete the reaction. The amount of hardener you add is dependent on the depth of the final casting. This way, as the hardener gets added and the glue darkens a little, the desired color is achieved. Most of the . 7oz of resin and a squirt of hardner. Ratio The ratio range for catalyst to resin is 1 to 2 percent hardener to the total volume of resin to be used. Too much resin and hardener mixed together produce too much heat too quickly. For every 10 F the temperature is raised above 70F, you can cut the cure time by 10%. -scraping the last polyester from the mixing cup, and using it. I think I . However, I'm afraid i didn't use enough hardener—there was 1/4 bottle left, with I used with one-quarter of the bottle of resin per the instructions. A large can or metal bowl will work, but it should be of a disposable nature. The resin and hardeners are unique to each system, you cannot mix and match. Stir the mixture together. This means for every ounce of cloth, you use 2 . If the room is any colder, this may affect the curing process. You should go with no less than 1% catalyst on resin, which is 1.28 oz's per gallon, 1.25% to 1.5% is better. Polyester resin has a little more give when it . 3. Also you cannot use one hardener from one epoxy system with another epoxy system. Stir the mixture well for about 1 minute without introducing too many air bubbles. Too much resin and hardener mixed together produce too much heat too quickly. I'm doing some wood finishing (on my drums, to be exact) with the polyester resin from a fiberglass kit I had lying around, you know, to make a hard reflective surface on the interior. Sc110 is a 1 to 1/2 ratio. It's basically epoxy, from what I gather. When the resin has cured, it should feel hard and smooth. Jul 22, 2007. What happens if you put too much hardener in resin? B. Adding hardener to polyester has a tendency to slightly darken the glue. No, the hardeners are not the same between epoxy and polyester. Click to see full answer Just so, how much catalyst do I need for polyester resin? Similarly, it is asked, how much resin do I need for fiberglass? I'm doing some wood finishing (on my drums, to be exact) with the polyester resin from a fiberglass kit I had lying around, you know, to make a hard reflective surface on the interior. 1. It's basically epoxy, from what I gather. It seems counterintuitive, but the thinner the casting, the more hardener you need. . This 2% ratio equates to about .625 CC per ounce of gelcoat. . The chart below indicates how much additive to add to wax-free gelcoat or polyester resin. Be careful while adding too much resin colorant: if you add too much colour pigments ( more than 6% of the total volume of your polyester resin and hardener combined ). Let's say you will use 100ml resin and hardener - total 100ml uv resin + 100ml hardener = 100ml, don't use more than 6% of colored dye ). Avoid using too much wax as it will result in fish eye and other undesirable results. Room temperature: The best temperature for the resin to cure fully is 75°F to 85°F (25°C to 30°C). General Formula for coverage of Epoxy resin to fiberglass cloth. For example, four drops of hardener will be 1 percent of 1 ounce of resin. How much catalyst do you need for polyester resin? Check that you're using the correct number of pump strokes: Use equal strokes of epoxy resin and . 20 parts resin / 4.2 parts hardener / 1.1 parts accelerator by weight. When using paints and other solvent-based colors in resin, these can sometimes speed up the resin curing reaction and cause the mixture to heat up too quickly. It seems counterintuitive, but the thinner the casting, the more hardener you need. Adding too much of either resin or hardener will alter the chemical reaction and the mixture will not cure . The correct ratio of hardener to resin should be calculated before the mixing process is begun to make it easier to monitor how much catalyst to dispense. Generally speaking, for Polyester Resins, the mixing ratio is 2% i.e. Example, one cup of resin would require ½ cup of hardener. 2. If all that's needed is a metal effect on the surface it's common practice to fill a small amount of catalysed resin richly with the metal powder (Tiranti recommends the same volume plus a little more) and apply a thin coat to the mould surface first before filling the rest with unfilled or pigmented resin Mix thoroughly according to the . You have to start with the end in mind. With that said, most systems utilize slow, fast, extra slow, extra fast hardeners. Measure an appropriate amount of resin in a metal container. Less MEKP gives a slower cure, more gives a faster cure. Any more and the fiberglass will not completely harden. Resin/hardener ratios must be exact! How much hardener do I need for a gallon of paint? 3. You have to start with the end in mind. While you can mix a volume of epoxy and use it as you please, polyester casting resin isn't that simple. Answer (1 of 4): Polyester resin cures (not dries out) by chemical reaction which initiates when the catalyst ( free radical initiator) MEKP is added and reacts with the accelerator ( usually Cobalt Octate , the pink or blue color in the resin) and creates exothermic (internal) heat which is what. Some require equal amounts of resin and hardener and some require a lesser amount of hardware to the resin that supplied. Watch the color. At the indicated time, add the hardener, filling the container to the right 8:1:1 level. Really deep green, you better work fast. In conclusion, resin and epoxy resin are the . Your resin and hardener could be off ratio Too much or too little hardener will affect the cure time and thoroughness of the cure. The ratio range for catalyst to resin is 1 to 2 percent hardener to the total volume of resin to be used. The amount of hardener you add is dependent on the depth of the final casting. 1. The shelf life . Operation: Mix the correct amount of hardener into the correct amount of resin. Polyester Resin Characteristics: Polyester resin is brittle and prone to micro-cracking. You're ready! The mid point of 1.5% is most common. Remove the uncured epoxy. Search: Sanding Epoxy Resin Between Coats. What does resin feel like when dry? This means that for each one part of resin you would add ½ part of hardener. Adding more of less of the catalyst agent will speed up or slow down the curing time for the resin. Which I suspect is the type in this instance. Adding too much of either resin or hardener will alter the chemical reaction and the mixture will not cure properly. MEKP can be added to polyester resin in the range of 1 to 2% by volume or weight. While you can mix a volume of epoxy and use it as you please, polyester casting resin isn't that simple. Resin can be mixed in a clean plastic container, but because it generates heat when it sets, extreme care should be taken if you use one. And of course the reverse is true. How to Thin Polyester Fiberglass Resin With Acetone Put on a respirator and a pair of rubber gloves. A general formula is to plan a ratio of 1:2.5 resin. I think I . Resin kits have a minimum and maximum mixing amount. Polyester Resin Polyester resin is the most popular resin used in the industry. 2. As a result, the amount of coloring that gets mixed into the glue before the hardener should be slightly lighter in color than the actual color desired. . You can decrease the cure time by raising the ambient temperature around the epoxy resin. Select a suitable mounting cup and place the clean, Resin kits have a minimum and maximum mixing amount. If one CC is roughly 30 drops as stated below that would put me at roughly 18.75 drops of MEKP per ounce of gelcoat. you do not want to add too much or too little MEKP to the resin. Uneven cure: -bad mixing. The hardener and accelerator can be premixed in advance. This is mainly because of the lower cost and the ease of use. Registered User. #10. If this is true which seems to be the issue I would be almost at half as much as I need being I put 11 drops per ounce of gelcoat versus 18-19 drops. So, that's it. How to easily fix this problem The catalyst was added too late in the mixing process. 20ml for every 1kg of Resin in working conditions at room temperature. If it's brittle, sticky, or bendy, this can be due to a number of reasons: Your mixed resin was not mixed properly (too much hardener). When using paints and other solvent-based colors in resin, these can sometimes speed up the resin curing reaction and cause the mixture to heat up too quickly. For example, four drops of hardener will be 1 percent of 1 ounce of resin.Adding more of less of the catalyst agent will speed up or slow down the curing time for the resin. Do not apply additional material over non-curing epoxy. Salto. However, I'm afraid i didn't use enough hardener—there was 1/4 bottle left, with I used with one-quarter of the bottle of resin per the instructions. See Clean Up & Removing. 1% for summer (to give maximum wetting time) and 2% for winter. Polyester resin can be thinned out using no more than 10 percent acetone. If not enough catalyst is used the resin will eventually get hard, but it will not be a good complete cure, so it won't be as strong as it should be. In general, the suggested Valspar hardener mix ratio can be 8oz to a gallon or 4oz to 1/2 gallon, 2oz to a quart. Re: Resin to hardener Ratio. A. All epoxy mixes are different. The ratio range for catalyst to resin is 1 to 2 percent hardener to the total volume of resin to be used. Too much hardener will actually make the cured epoxy rubbery. When adding it to gelcoat, you must also add the MEKP (methyl ethyl ketone peroxide) hardener. However, adding less than 1 percent or more than 2 percent will . The other type is polyester resin, smells like bondo. For polyester Gelcoats used in a moulding situation, we recommend from 2% to 2.5%catalyst. We recommend using between 1.25% to 1.75% (1 2/3 ounce to 2 1/3 ounce per gallon). . A rule of thumb for polyester laminating resin is between 1% and 2% i.e. Mixing out of the above range will result in a weaker cured resin. (polyester which is on the walls of the mixing cup is hardly mixed with curing agent) -MEKP gone bad (less likely, then the whole batch would take longer to cure (geltime drift) -resin gone bad (again, not likely.