# Best resin casting powder: water ratio, finish and bag sizes Source: https://resinandmold.com/best/best-resin-casting-powder Publisher: Resin and Mold. Picks are chosen from what each Amazon listing states, not from hands-on tests. Method: https://resinandmold.com/how-we-pick Resin casting powder is not resin. It is a water-mixed, plaster-type powder that sets opaque white in a silicone mold, with no hardener and no lamp, which is why it shows up in videos as eco resin. The bags look alike, so the useful differences are in the numbers each listing gives: the powder to water ratio (3:1 or 10:3 by weight in this group), the demold time, the full cure time, the bag weight and whether pigments or a sealer come in the box. This guide compares six powders from six brands on those points. Nothing was mixed or poured for it. Two things apply to every bag: the ratio is by weight, so use a scale, not a cup, and the cured piece is porous until sealed, so trays and coasters need a varnish or sealer before they meet water. Ratios differ by brand, so follow your own label rather than a number from another bag. ## Picks ### 1. LET'S RESIN Resin Casting Powders 3000g,20~30 Minutes De-Mold Ceramic Resin Powder to water: 3:1 by weight; Demold: 25-30 minutes; Full cure: 2 hours; Extras included: none listed A 3000 g bag of plaster casting powder mixed 3:1 with water by weight. The listing states demolding in 25 to 30 minutes and full cure in 2 hours, and a thin, water-like mix for detailed molds. What the listing offers: - Ratio, demold time and full cure are all stated: 3:1 by weight, 25 to 30 minutes and 2 hours. - The listing describes a thin, water-like consistency that fills even tiny crevices in a mold. - Dries to an opaque white and takes pigments, mica, glitter, sand and gold leaf during mixing, per the listing. Limits to know: - No sealer, pigments or tools are listed, so varnish and colorants are a separate purchase. - The listing warns that tiny details may break off if a piece is demolded before it has fully cured. ### 2. Eco Resin Casting Powders 4500g - All-in-One Casting Resin Kit for Beginners, Water-Based ＆ Fast Curing, 20-30 Minutes Demold - Water Activated Plaster Powder for Crafts, Art, DIY Home Decor Powder to water: 10:3 by weight; Demold: 25-30 minutes; Full cure: 2-6 hours; Extras included: varnish, 6 paints, tools A 4500 g powder kit with gloss varnish, six water-based acrylic paints, cups, stirrers, measuring tools and gloves. Mixed 10:3 with water by weight; demold in 25 to 30 minutes, full cure in 2 to 6 hours. What the listing offers: - Includes the sealer: a gloss varnish comes in the kit, along with 6 water-based acrylic paints. - Stirrers, cups, measuring tools and gloves are included, so a beginner needs only water and molds. - The listing gives the full process: 10:3 by weight, stir 2 to 3 minutes, demold in 25 to 30 minutes. Limits to know: - Full cure is given as a range of 2 to 6 hours, longer than the 2 hours most other listings state. - The size of the varnish bottle and paints is not stated, so it is unclear how much of the 4500 g they cover. ### 3. Resin Casting Powder 5000g (Package Upgrade), 20~30 Minutes Plaster Powder Powder to water: 3:1 by weight; Demold: 25-30 minutes; Full cure: 2 hours; Extras included: none listed The largest bag in this guide: 5000 g of gypsum casting powder mixed 3:1 with water by weight. The listing states demolding in 25 to 30 minutes and a full cure in 2 hours. For bulk trays and decor. What the listing offers: - 5000 g in one package suits bulk pours such as sets of trays, planters and candle holders. - The listing is clear that 3:1 is by weight, not volume, and that water can be adjusted for consistency. - Described as a fine powder with good bubble release that dries to an opaque white. Limits to know: - No sealer or pigments are listed, and the cured piece is porous until it is sealed. - The title says 20 to 30 minutes and the bullets say 25 to 30 for demolding, a small mismatch in the listing. ### 4. Eco Resin Casting Powder - 100oz / 2800g Fast Cured Plaster Casting Powder for Beginners - 20~30 Minutes Demold, Easy Mixing Water Activated Eco-Friendly Casting Resin for DIY Crafts Making, Home Art Powder to water: 10:3 by weight; Demold: 25-30 minutes; Full cure: 2 hours; Extras included: none listed A 100 oz (2800 g) bag of plaster casting powder mixed 10:3 with water by weight. The listing states demolding in 25 to 30 minutes and full cure in 2 hours, with a porcelain-like white finish. What the listing offers: - States a 10:3 weight ratio, a 2 minute stir after adding pigment, demold in 25 to 30 minutes and full cure in 2 hours. - The listing describes the cured surface as smooth and porcelain-like, from a fine, pure white powder. - A mid-size 2800 g bag; DecorRom also lists a 1400 g bag of the same powder for a smaller first try. Limits to know: - No sealer, pigments or tools are listed with the bag, so those are separate purchases. - One bullet says to wait 30 minutes to cure while another gives 2 hours for full cure, so read 30 minutes as demold time. ### 5. OSBANG Plaster Casting Powder 1000G/35 OZ, Water Activated Fast Curing Plaster Casting Powder, 20-30 Minutes Demold, Easy Mixing & Beginners Friendly Casting Powder for Resin Molds, Crafts & DIY Art Powder to water: 10:3 by weight; Demold: 25-30 minutes; Full cure: about 2 hours; Extras included: none listed A 1000 g (35 oz) bag of water activated plaster casting powder. The listing gives 10:3 by weight as the faster curing ratio, a 25 to 30 minute demold and about 2 hours to cure. What the listing offers: - The listing explains how the ratio changes the set: 10:3 cures faster than 3:1, which is faster than 2:1. - States plainly that the cured piece is porous and not watertight, and recommends a wax, acrylic sealer or varnish. - A 1000 g bag is a small, low-commitment size for trying casting powder in a few molds. Limits to know: - At 1000 g it is the smallest size here and will not go far on large trays. - No pigments, sealer or measuring tools are listed with the bag, so those are separate purchases. ### 6. JDiction ResinCrete, 1000G Water-Based Eco-Friendly Formula, 20-30 Minutes Demold Fast Curing Eco Casting for Beginners, Mineral Casting Powder, Easy Mix for DIY Home Art Powder to water: 10:3 by weight; Demold: 20-30 minutes; Full cure: not stated; Extras included: none listed A 1000 g bag of ResinCrete, a water-activated mineral casting powder mixed 10:3 with water by weight. The title gives a 20 to 30 minute demold; the listing says it cures as smooth as porcelain. What the listing offers: - The listing gives a 10:3 weight ratio and says to stir until the mix is completely smooth, like yoghurt. - Described as a fine, pure white powder that cures as smooth as porcelain, for terrazzo and marble style trays. - Also listed in a 3000 g bag, so the same powder can be bought larger once the small bag is used up. Limits to know: - No full cure time appears in the listing; it only says the powder cures quickly in 30 minutes. - No sealer or pigments are listed, and at 1000 g it suits small pieces only. As an Amazon Associate I earn from qualifying purchases.