Description
This cost-effective, semi-rigid urethane casting resin cures quickly to a durable plastic with excellent impact resistance.
Smooth-Cast™ 66D features a 1A:1B mix ratio by volume and a low viscosity, minimizing bubble entrapment.
It is ideal for creating impact-resistant prototypes, models, toys, props, and climbing holds.
This grey resin has a pot life of 7 minutes and a demold time of 60 minutes.
Smooth-Cast™ 66D supports vibrant color customization with SO-Strong™, UVO™, or Ignite™ colorants.
Note that it is not suitable for rotational casting.
- Shore Hardness: 66D
- Working time: 7 min
- Demold time: 60 min
- Mix ratio: 1A:1B by volume
Instructions
Safety:
- Store and use materials in a warm environment at 23°C.
- Products have a limited shelf life; use promptly.
- Liquid urethanes are moisture-sensitive; they absorb atmospheric moisture.
- Mixing tools and containers should be clean and made of metal, glass, or plastic.
- Mix in a well-ventilated area.
- Wear safety glasses, long sleeves, and rubber gloves to minimize contamination risk.
Applying a Release Agent:
- A release agent is necessary for demolding when casting into or over most surfaces.
- Use a mold-specific release agent like Universal™ Mold Release or Mann’s Ease Release™ 200.
- Apply a liberal coat of release agent on all surfaces in contact with the plastic.
- For thorough coverage, brush the release agent with a soft brush, then apply a light mist coating.
- Let the release agent dry for 30 minutes.
- Smooth-On silicone rubber molds typically do not require a release agent unless casting silicone into the mold.
Measuring & Mixing:
- Ensure Parts A and B are at room temperature (23°C).
- Combine equal volumes of Parts A & B in a mixing container.
- Scrape the bottom and sides of the container several times during mixing.
- Do not delay between mixing and pouring.
- Higher mass concentration accelerates gelling and curing.
- Shelf life reduces after opening; use remaining product quickly.
- Replace lids immediately after dispensing to prolong shelf life.
- XTEND-IT™ Dry Gas Blanket can significantly extend shelf life.
Pouring:
- Pour the mixture at the lowest point of the containment field to minimize air entrapment.
For Best Results:
- Use pressure casting by placing the casting assembly in a pressure chamber at 4.2 kg/cm² (60 PSI) for full cure time.
Curing:
- Ensure room-size ventilation or proximity to a forced air vent.
- Do not inhale fumes; they dissipate quickly with adequate ventilation.
- Castings may be hot and irritate skin immediately after curing; let cool before handling.
- Demold time varies with mass and mold configuration.
Performance:
- Cured castings are durable, resist moisture, solvents, and moderate heat.
- They can be machined, primed, painted, or bonded to other surfaces (remove any release agent first).
- Unpainted castings may yellow over time, especially under UV exposure.
- Conduct a small test application to ensure suitability for your project.
