Alja-Safe

What is Alja-Safe?

Alja-Safe is the world's first crystalline silica-free alginate specifically designed for safe, professional lifecasting. Developed by Smooth-On, the industry leader in moulding materials, Alja-Safe revolutionises body casting by eliminating harmful crystalline silica—a known carcinogen found in traditional alginates.

Perfect for creating detailed moulds of hands, feet, faces, and other body parts, Alja-Safe captures every fingerprint, wrinkle, and skin texture with remarkable precision. Whether you're a parent creating precious baby keepsakes, an artist crafting lifecast sculptures, or a special effects professional making realistic prosthetics, Alja-Safe delivers museum-quality results every time.

Why Artists and Makers Choose Alja-Safe:

The beauty of Alja-Safe lies in its simplicity and safety. This skin-safe alginate has been independently tested and certified for direct skin contact, making it suitable for all ages—from newborns to elderly family members. Unlike other body moulding materials that require complex mixing ratios or pose health risks, Alja-Safe uses a straightforward 1:1 powder-to-water ratio and cures in just 8-10 minutes.

Rowe Advanced Materials is Australia's official distributor of Smooth-On products, offering fast shipping across the country and expert technical support to ensure your lifecasting projects succeed. With over 20 years of industry experience, we're here to help you choose the right materials and techniques for your specific application.

Create Your First Lifecast: Step-by-Step Guide

Making a lifecast with Alja-Safe is easier than you might think. Follow these simple steps to capture a perfect mould:

Step 1: Gather Your Materials

• Alja-Safe powder (we recommend 1lb for a single hand)
• Water at room temperature (80°F/27°C is ideal)
• Mixing container (large enough to immerse the body part)
• Mixing bowl and stirrer
• Plaster or casting resin
• Petroleum jelly or hand cream (optional, for easier removal)

Step 2: Prepare Your Subject

Remove all jewellery and wash hands thoroughly. For hairy areas, apply a thin layer of petroleum jelly to prevent discomfort during demoulding. Choose the pose carefully—once you start, the position must be held still for 8-10 minutes.

Step 3: Mix the Alginate

Measure equal parts Alja-Safe powder and water by volume (not weight). Add the powder to the water gradually while stirring continuously. Mix for about 1-2 minutes until you achieve a smooth, lump-free consistency similar to thick pancake batter. Work quickly but thoroughly—your working time is approximately 5 minutes.

Pro Tip: Warmer water speeds up curing, while cooler water extends working time. Adjust water temperature based on the complexity of your mould.

Step 4: Pour and Position

Pour the mixed Alja-Safe into your container, filling it about halfway. Slowly insert the hand or body part into the alginate, keeping it centred without touching the sides or bottom. Hold the position completely still. The alginate will change from a gel-like liquid to a firm rubber consistency—this takes 8-10 minutes.

Step 5: Test and Demould

To test if the mould is ready, gently press the surface with your finger. It should feel firm and springy, not sticky. Once cured, carefully wiggle fingers or toes to break the seal, then slowly withdraw the body part. The mould is now complete and ready for casting.

Step 6: Cast Your Reproduction

Alja-Safe moulds are temporary and should be used within 4 hours for best results. You can cast into them using:

• Plaster (included in starter kit) - Traditional, affordable option
• duoMatrix NEO - Polymer-modified gypsum for stronger casts
• Smooth-Cast 300Q - Ultra-fast urethane resin for durable reproductions
• Dragon Skin silicone - For soft, skin-like castings

Mix your casting material according to instructions and pour into the mould. Let it cure completely before demoulding your finished lifecast.

Everything You Need to Know About Alja-Safe

Is Alja-Safe safe for babies and children?

Yes, absolutely. Alja-Safe is independently tested and certified as skin-safe for all ages. It contains no crystalline silica (a known carcinogen found in traditional alginates) and is non-toxic. Thousands of parents worldwide use Alja-Safe to create precious baby hand and footprint keepsakes. Always supervise children during the casting process and ensure they can hold still for 8-10 minutes.

How long does an Alja-Safe mould last?

Alja-Safe creates temporary moulds that should be used within 4 hours of demoulding for best results. Alginate moulds are water-based and will begin to shrink and deteriorate over time. For this reason, cast into your mould as soon as possible. If you need a reusable mould, we recommend Body Double silicone rubber instead.

Can I reuse Alja-Safe moulds?

No, Alja-Safe moulds are designed for single-use or possibly two reproductions if used immediately. The mould material is delicate and will tear during demoulding of rigid castings. For projects requiring multiple castings, use the Alja-Safe mould to create a plaster positive, then make a durable production mould using silicone rubber.

What can I cast into Alja-Safe moulds?

You can cast a variety of materials into Alja-Safe moulds:

• Plaster - Traditional, affordable, readily available
• duoMatrix NEO - Polymer-modified gypsum (stronger than plaster)
• Smooth-Cast 300Q - Ultra-fast urethane resin for rigid reproductions
• Fast-setting platinum silicone (Dragon Skin FX Pro) - For soft, skin-like castings
• Wax - For decorative or lost-wax casting applications

Avoid slow-curing materials as the mould will deteriorate before they fully set.

How much Alja-Safe do I need?

This depends on the size of the body part and container:

• Single adult hand: 1-1.5 lbs (starter kit is perfect)
• Two clasped hands: 2-3 lbs
• Adult foot: 1.5-2 lbs
• Baby hand or foot: 0.5-1 lb
• Face casting: 3-5 lbs (use Alja-Safe Acrobat)

Calculate volume by filling your container with water, then measuring it. You'll need roughly equal parts alginate powder to water.

Can Alja-Safe be used for dental applications?

No. This product has not been tested for dental use and should not be used for dental moulds or applications. Use dental-specific alginates for any dental work.

Why did my mould tear during demoulding?

This typically happens when:

• The mould wasn't fully cured (wait full 8-10 minutes)
• The subject moved during setting
• Undercuts or tight spaces prevented clean release
• The mould was too thin (ensure adequate thickness around all areas)

For complex shapes, consider making a two-part mould or using a support shell.

How do I prevent air bubbles in my casting?

Air bubbles form when air gets trapped against the mould surface. To minimize bubbles:

• Pour casting material slowly and steadily
• Tap or vibrate the mould gently after pouring
• For important details, paint a thin layer of casting material into the mould first, then fill
• Tilt and rotate the mould to help air escape

Does water temperature affect Alja-Safe?

Yes, significantly. Warmer water (above 80°F/27°C) accelerates the curing process, giving you less working time but faster demould. Cooler water (below 70°F/21°C) extends working time but takes longer to cure. Room temperature water (around 80°F/27°C) provides the ideal balance of 5 minutes working time and 8-10 minutes cure time.

Where can I buy Alja-Safe in Australia?

Rowe Advanced Materials is Australia's official Smooth-On distributor. Order online through our website for fast delivery to any Australian address, or visit one of our physical locations in Adelaide, Melbourne, Sydney, or New Zealand. We maintain local stock of all Alja-Safe products for immediate dispatch.

Can I add colour to Alja-Safe?

Alja-Safe itself cannot be coloured as it's a temporary mould material, not the final casting. However, you can add colour to the materials you cast into the mould—plaster accepts paint beautifully, while resins can be tinted with pigments before casting.

What's the difference between Alja-Safe and Body Double?

Alja-Safe is an alginate that creates temporary, single-use moulds that cure in 8-10 minutes. Body Double is a platinum silicone rubber that creates permanent, reusable moulds but requires 30 minutes to cure. Choose Alja-Safe for quick projects and one-off castings; choose Body Double when you need to make multiple reproductions from the same mould.