Product Overview
TASK™ 5 is a premium, high-performance casting resin designed to deliver superior physical properties for a variety of demanding applications. Yielding exceptionally tough, tan-coloured castings, this resin is virtually bubble-free without the need for vacuum degassing, saving you time and equipment costs. Formulated with high tensile and flexural strength, as well as a high flexural modulus, TASK™ 5 is the perfect solution for industrial applications, pattern making, and creating highly detailed prototype models. It is specifically designed for casting in thicknesses up to 1/2″ (1.27 cm).
Processing Recommendations
Preparation
- Materials should be stored and used in a warm environment (73°F/23°C).
- This product has a limited shelf life and should be used as soon as possible.
- All liquid urethanes are moisture-sensitive and will absorb atmospheric moisture. Always use in a low-humidity environment (below 50% RH).
- Mixing tools and containers should be clean and made of metal, glass, or plastic.
- Mixing containers should have straight sides and a flat bottom. Mixing sticks should be flat and stiff with defined edges for scraping the sides and bottom of your mixing container.
- Mixing should be done in a well-ventilated area. Wear safety glasses, long sleeves, and rubber gloves to minimise contamination risk.
Because no two applications are quite the same, a small test application to determine suitability for your project is recommended.
Applying A Release Agent
- A release agent is necessary to facilitate demoulding when casting into or over most surfaces.
- Use a release agent made specifically for mould making, such as Universal™ Mold Release or Mann’s Ease Release™ 200.
- A liberal coat of release agent should be applied onto all surfaces that will contact the plastic. To ensure thorough coverage, apply the release and brush with a soft brush over all surfaces.
- Follow with a light mist coating and let the release agent dry for 30 minutes.
- Smooth-On silicone rubber moulds usually do not require a release agent unless casting silicone into the mould, though applying one will prolong the life of the mould.
Measuring & Mixing
- The proper mixing ratio of TASK™ 5 is 1A:1B by weight or volume.
- Dispense the required amount of Part A into a mixing container, then measure out the appropriate amount of Part B and combine.
- Shake or stir Part A & Part B before using.
- Stir slowly and deliberately, making sure that you scrape the sides and bottom of the mixing container several times. Be careful not to splash the low-viscosity material out of the container.
- If tinting or pigmenting, add the tint or pigment dispersion to Part B and mix thoroughly before adding Part A.
Pouring, Curing & Performance
Pouring
- If casting into a rubber mould, pour the mixture in a single spot at the lowest point of the mould.
- If encapsulating an object, do not pour the mixture directly over the object; let the mixture seek its level. A uniform flow will help minimise entrapped air.
Vacuum Degassing & Pressure Casting
- The mixed resin is low in viscosity and does not require vacuum degassing.
- If you choose to vacuum the material, subject the mixture to 29 h.i.g. mercury in a vacuum chamber until the mixture rises, breaks, and falls. Allow for 3 to 4 times volume expansion in the mixing container, and be acutely aware of the brief 3-minute pot life so the material does not set up before pouring.
- Although not necessary for most applications, best results for eliminating air/bubbles are obtained using a pressure casting technique. Place the mould into a safety-rated pressure chamber and subject the mixture to 60 PSI (4.2 kg/cm2) until the material cures. After the material cures, wait 30 minutes before releasing pressure and removing the casting.
Curing & Post-Curing
- For most applications, room temperature curing at 73°F (23°C) for 24 hours is adequate. Low mass or thin-walled castings will take longer to cure. Castings will reach their ultimate physical properties at room temperature in 7 days.
- Post Curing Option: Castings will reach “full cure” faster and achieve maximum physical properties/heat resistance if heat post-cured in a dedicated shop oven. This is highly recommended if castings are thin or of low mass concentration. Castings should be post-cured in a mould or support structure. Allow the material to cure for 3 hours at room temperature followed by 4 hours at 150°F (65°C). Allow the casting to cool to room temperature before handling.
Demoulding & Performance
- The demould time of the finished casting depends on mass and mould configuration.
- Make sure the casting has reached handling strength before demoulding. If the casting has a flat back, it can be removed from the mould and allowed to cure outside on a flat, level surface to attain full working properties. Allow the material to cure for 24 hours at room temperature before putting into service.
- Cured castings of TASK™ 5 are rigid and durable. They resist moisture, moderate heat, solvents, and dilute acids. They can be machined, primed/painted, or bonded to other surfaces provided any release agent is completely removed. Castings can be displayed outdoors after proper priming and painting.
