Flex 50 Flexible Urethane Rubber
Flex 50 is a medium-firm urethane rubber designed for casting flexible molds, replicating soft rubber parts, and creating durable prototypes. With a shore hardness of 50A, it provides the perfect balance between strength and flexibility, making it an excellent choice for gaskets, grips, and high-detail molds.
Its low viscosity ensures superior detail reproduction, while vacuum or pressure casting is recommended for bubble-free results.
Features
✅ Medium-Firm Flexibility:
Shore hardness of 50A for a balance of strength and flexibility
✅ Perfect for Rubber Molds & Parts:
Ideal for casting flexible molds, gaskets, and soft rubber parts
✅ Smooth, Detailed Castings:
Low viscosity allows for excellent detail reproduction
✅ Customizable Colors:
Mix with Alumilite translucent dyes, and add white dye for opaque colors
✅ Fast Demold Time:
Ready to demold in 2 hours, full cure in 72 hours
✅ Compatible with Multiple Casting Materials:
Works well with resin, concrete, plaster, and more
✅ Minimal Shrinkage:
Maintains high accuracy with low linear shrinkage
🚫 Not as rigid as higher shore rubbers like Flex 70 or 80
FAQ
What is Flex 50 used for?
✅ Flex 50 is great for making flexible rubber molds and replicating soft rubber parts for applications like prototyping, gaskets, and craft projects. It works well with resin, concrete, plaster, and other casting materials.
How flexible is Flex 50?
💪 With a shore hardness of 50A, Flex 50 provides a balanced mix of durability and flexibility, making it softer than Flex 70 but still tough enough for high-quality castings.
Do I need a vacuum or pressure chamber?
🫧 While it's not required, using a vacuum or pressure casting setup helps eliminate air bubbles, ensuring smooth, detailed results every time.
Can I add color to Flex 50?
🎨 Absolutely! Use Alumilite’s translucent dyes to tint your castings, but if you need an opaque finish, be sure to mix in white dye.
How long does Flex 50 take to cure?
⏳ You can demold in 2 hours at room temperature, though full cure takes 72 hours.
How should I store my urethanes to keep them in the best condition?
❄️ Store your urethanes in a cool, dark place away from direct sunlight and high temperatures, ideally between 60°F and 75°F (15°C to 24°C). Keep the container tightly sealed to prevent moisture and air from affecting the formula. Wiping the container tops before sealing can help prevent stuck caps.
What are the best conditions for pouring and displaying urethane projects?
☀️ For the best results, pour urethanes in a well-ventilated, temperature-controlled environment with humidity below 60% to prevent defects and bubbles. Once cured, keep finished projects out of direct sunlight to prevent discoloration or degradation.
Downloadable Resources
Need Help Getting Started?
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Strong Yet Flexible
Watch Flex 50 in action as it bends, flexes, and holds its shape while staying strong. This versatile urethane rubber is perfect for creating flexible, impact-resistant parts for a wide range of applications. Its balanced strength and flexibility make it ideal for props, grips, handles, gaskets, and protective padding.
Whether you're crafting realistic special effects props, durable prototypes, or soft yet tough components for industrial and automotive use, Flex 50 provides the perfect combination of durability and flexibility.
Built Tough, Designed to Bend
Flex 80 is the perfect choice when you need extreme durability with just the right amount of flexibility. Whether you're casting industrial rubber parts, fixtures, or molds, this urethane rubber delivers high tensile strength, tear resistance, and precision detail with minimal shrinkage. Its toughness rivals hard rubber components, making it ideal for applications where strength and resilience are a must.
Plus, with a fast 2-hour demold time and the ability to create opaque colors, Flex 80 is as efficient as it is reliable. If you need a tough, long-lasting casting material, Flex 80 is the go-to solution!
