--- product_id: 48505789 title: "Smooth Cast® 300 Liquid Plastic Urethane Casting Resin - Trial Unit" brand: "smooth-on" price: "€ 106.80" currency: EUR in_stock: true reviews_count: 10 category: "Smooth On" url: https://www.desertcart.pt/products/48505789-smooth-cast-300-liquid-plastic-urethane-casting-resin-trial-unit store_origin: PT region: Portugal --- # ultra low viscosity 15 min fast cure 1:1 mix ratio Smooth Cast® 300 Liquid Plastic Urethane Casting Resin - Trial Unit **Brand:** smooth-on **Price:** € 106.80 **Availability:** ✅ In Stock ## Summary > ⚡ Cast like a pro, cure like a boss! ## Quick Answers - **What is this?** Smooth Cast® 300 Liquid Plastic Urethane Casting Resin - Trial Unit by smooth-on - **How much does it cost?** € 106.80 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.pt](https://www.desertcart.pt/products/48505789-smooth-cast-300-liquid-plastic-urethane-casting-resin-trial-unit) ## Best For - smooth-on enthusiasts ## Why This Product - Trusted smooth-on brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Rapid 15-Minute Cure:** Get flawless, durable castings faster than ever—perfect for tight deadlines. - • **Effortless 1:1 Mix Ratio:** Simplify your workflow with an easy, precise equal-part mixing system—no guesswork needed. - • **Ultra-Low Viscosity Flow:** Pour with ease and achieve bubble-free, bright white results every time—no vacuum degassing required. - • **Moisture & Solvent Resistant:** Create tough, long-lasting pieces that stand up to everyday wear and tear. - • **Versatile Finish-Ready Material:** Sand, prime, and paint your castings to perfection for professional-grade prototypes and props. ## Overview Smooth Cast® 300 is a premium liquid urethane resin designed for ultra-low viscosity, fast 15-minute curing, and a simple 1:1 mix ratio. It produces bright white, rigid, and durable castings that require no vacuum degassing and can be easily sanded, primed, and painted—ideal for sculptors, prototypers, and special effects artists seeking flawless, professional results. ## Description Smooth-On Smooth Cast 300 Series of liquid plastics are ultra-low viscosity casting resins that yield castings that are bright white and virtually bubble free. Vacuum degassing is not necessary. They offer the convenience of a one to one mix ratio (one part A to one part B by volume). Fully cured castings are tough, durable, machinable and paintable. They resist moisture and mild solvents. Applications for Smooth-Cast Liquid Plastics include reproducing small to medium size sculptures,making prototype models, roto cast pieces, and special effect props. Review: Awesome - Very good bought lots of this and will buy lots more easy to work with and great results all round Review: Pefect casr first time - I had tried another brand of resin and had lots of issues with it not setting or only working with one type of silicone. There is no problem with this product; I mixed, pored and after 10 minutes had a perfect copy. Will use again. ## Features - Causes skin irritation. - Harmful if inhaled. - May cause allergy or asthma symptoms or breathing difficulties if inhaled. - May cause an allergic skin reaction. - May cause damage to organs through prolonged or repeated exposure. - May cause respiratory irritation. - Suspected of causing cancer. - 15 minute cure time - Rigid white plastic - Low viscosity - easy to pour - 1A:1B by volume mix ratio - Can be sanded, primed and painted ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B004BN7G0E | | Best Sellers Rank | 449,617 in Home & Kitchen ( See Top 100 in Home & Kitchen ) 1,386 in Sculpting Moulding & Casting | | Brand | Smooth-On | | Compatible Material | Plastic | | Customer Reviews | 4.7 4.7 out of 5 stars (1,123) | | Grit Material Type | Plastic | | Grit Number | 300 | | Grit Type | Fine | | Item Dimensions | 18.8 x 15.2 x 7.9 centimetres | | Item Weight | 907 g | | Manufacturer | Smooth-On, Inc. | | Material | Urethane | | UPC | 751635476417 | | Unit Count | 1.0 count | ## Product Details - **Brand:** Smooth-On - **Grit material:** Plastic - **Grit type:** Fine - **Item dimensions L x W x H:** 18.8 x 15.2 x 7.9 centimetres - **Material:** Urethane ## Images ![Smooth Cast® 300 Liquid Plastic Urethane Casting Resin - Trial Unit - Image 1](https://m.media-amazon.com/images/I/81gwmekNnqL.jpg) ![Smooth Cast® 300 Liquid Plastic Urethane Casting Resin - Trial Unit - Image 2](https://m.media-amazon.com/images/I/71ZWTS1-Q2L.jpg) ![Smooth Cast® 300 Liquid Plastic Urethane Casting Resin - Trial Unit - Image 3](https://m.media-amazon.com/images/I/81ubKEjBDDL.jpg) ![Smooth Cast® 300 Liquid Plastic Urethane Casting Resin - Trial Unit - Image 4](https://m.media-amazon.com/images/I/71Koo4ru1vL.jpg) ![Smooth Cast® 300 Liquid Plastic Urethane Casting Resin - Trial Unit - Image 5](https://m.media-amazon.com/images/I/71LJ0Lk-VZL.jpg) ## Available Options This product comes in different **Color** options. ## Questions & Answers **Q: Can I add glitter to this?** A: I've used 325 with glitter pigments, and it works very well. You'll have to add a decent amount of glitter and it will take longer to cure. **Q: Can I use this to cast a dome-shaped mask using a silicone mold? Will it stay liquid long enough for me to tilt it back & forth to form an even coat?** A: Smooth-Cast 300 is a snap cure material - a better choice may be Smooth-Cast 325 or Smooth-Cast 65D, both of which have a gradual cure profile. **Q: is it machinable?** A: Yeah, to an extent. I’ve taken a dremle tool to casted plastic to sand down parts and remove unwanted flashing that occurs. It’s pretty tough stuff, let it cure for a day or two before sanding or working on thinner areas, but I’ve even taken a hacksaw to some castings and they have held up just fine. **Q: Is this a silicone or a urethane?** A: This is a urethane casting resin. ## Customer Reviews ### ⭐⭐⭐⭐⭐ Awesome *by S***N on 8 November 2020* Very good bought lots of this and will buy lots more easy to work with and great results all round ### ⭐⭐⭐⭐⭐ Pefect casr first time *by C***G on 2 September 2016* I had tried another brand of resin and had lots of issues with it not setting or only working with one type of silicone. There is no problem with this product; I mixed, pored and after 10 minutes had a perfect copy. Will use again. ### ⭐⭐⭐⭐⭐ Five Stars *by A***R on 23 October 2017* Good buy. A little expensive. But works as moulds .u have to work fast and accurate ## Frequently Bought Together - Smooth-Cast™ 300: Bright White, Low Viscosity, Liquid Plastic Casting Resin - Pint Unit - Smooth-On Mold Star™ 16 Fast Platinum Silicone Rubber, Silicone Mold Making Kit - Pint Unit - Smooth-On Universal Mold Release - 14 Fluid Ounce Aerosol Can --- ## Why Shop on Desertcart? - 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016 - 🌍 **Shop Globally** — Access 737+ million products across 21 categories - 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price - 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members) - 🔒 **Secure Payments** — Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.pt/products/48505789-smooth-cast-300-liquid-plastic-urethane-casting-resin-trial-unit](https://www.desertcart.pt/products/48505789-smooth-cast-300-liquid-plastic-urethane-casting-resin-trial-unit) --- *Product available on Desertcart Portugal* *Store origin: PT* *Last updated: 2026-04-24*