How to make DIY plaster objects: step-by-step guide and ideas

TL;DR: To make DIY plaster objects you need Aqua Resin, cold water, a silicone mould and a scale. Weigh 100 g of powder for every 30 g of water, mix, pour into the mould, demould after 30 minutes and let it dry for 24 hours. Then you can sand, colour or make the piece water-resistant.

Introduction

Making DIY plaster objects is one of the easiest ways to create decorations, gifts and small home accessories with your own hands. All it takes is a few materials and a bit of method: the secret lies in the mix, the pour and the demoulding time.

In this guide we look at what you need, how to work with plaster step by step and which plaster creations you can make, from small vases to hand and foot casts.

Contents

• Key points
• Which plaster to choose
• What you need
• How to work with plaster step by step
• Mix ratios and times
• DIY plaster object ideas
• Colouring, finishing and protecting
• Common mistakes
• Recommended products
• FAQ

Key points

• Basic mix: 100 g of Aqua Resin for every 30 g of cold water.
• Demould after 30 minutes, full drying in 24 hours.
• Silicone moulds don't need a release agent.
• Aqua Resin is not an epoxy resin: it is a premium alpha plaster, non-toxic and water-based.

Which plaster to choose

Ordinary plaster is fine for simple jobs, but for decorative objects an alpha plaster makes all the difference: it is denser and stronger, captures fine mould details and gives smooth surfaces with a porcelain effect. Aqua Resin is an alpha plaster designed for creative crafts, also available in Black and Terracotta Roma. To learn more, read our comparison plaster vs alpha plaster.

What you need

• Alpha plaster, such as Aqua Resin.
• Cold water.
• Kitchen scale to weigh powder and water.
• Container and spatula for mixing.
• Silicone moulds: you'll find shapes for vases, trinket trays, candle holders and decorations in our moulds and accessories collection.
• Fine sandpaper for finishing.
• Optional: Aqua Pigment to colour the mix and Aqua Shield to make the piece water-resistant.

How to work with plaster step by step

1. Prepare the mould. It should be clean and dry, on a stable surface. Silicone doesn't need a release agent.
2. Weigh powder and water. 100 g of Aqua Resin for every 30 g of cold water: guessing quantities is the main cause of fragile pieces.
3. Mix. Add the powder to the water and mix calmly until fluid, creamy and lump-free.
4. Pour. Pour slowly into the mould so the plaster reaches every detail, then tap the mould on the work surface to release air bubbles.
5. Demould after 30 minutes. Remove the piece gently and let it dry completely for 24 hours.
6. Finish. Sand any rough edges with fine sandpaper, then colour or protect the piece.

Pro tip: only mix as much as you can pour within a few minutes: plaster starts to set quickly, and a thickening mix doesn't capture details well.

Mix ratios and times

DIY plaster object ideas

1. Hand and foot casts

The most moving keepsake: a newborn's hand, a couple's intertwined hands, the whole family together. The Love Cast Kit has everything you need for a 3D cast of hands and feet. For the technique in detail, follow our guide to hand and foot casts in 5 steps.

2. Vases, trinket trays and candle holders

These are the most popular objects for decorating the home. For vases and candle holders, add Aqua Shield, which makes them resistant to water and wax: all the details are in our guide on how to waterproof plaster.

3. Party favours

Hearts, stars, flowers and small symbolic shapes: with small moulds you can make dozens of identical favours in no time. Find inspiration in our original DIY party favour ideas.

4. Scented plaster

Plaster is porous and holds scent well: just add a few drops of your own essence to the mix. Follow our scented plaster guide, and don't use Aqua Shield, which would block the fragrance.

5. Bold-coloured ornaments

For objects with strong character, start from a plaster that is already coloured throughout: Aqua Resin Terracotta Roma for a terracotta look, Aqua Resin Black for a deep black.

6. Seasonal decorations

Tree ornaments, place cards, Halloween decorations like the plaster witch's hand: plaster suits every holiday. For Christmas, find all the ideas in our guide to plaster Christmas decorations.

Colouring, finishing and protecting

• Colour throughout: add Aqua Pigment to the water before adding the powder, for an even colour through the whole piece.
• Surface colour: paint the piece once it is completely dry, after 24 hours.
• Smooth surface: sand with fine sandpaper, without pressing on the details.
• Water protection: use Aqua Shield in the mix, brushed on or by dipping.

Common mistakes

• Guessing quantities. Too much water makes the piece fragile; too little makes it lumpy.
• Mixing too hard. It traps air and creates bubbles on the surface.
• Demoulding too early or painting a damp piece. Stick to the 30 minutes and the 24 hours.
• Using Aqua Shield in scented plaster. It blocks the fragrance.

For the full list, read the most common mistakes when working with plaster.

Recommended products

• Aqua Resin — premium alpha plaster, porcelain-white, demoulds in 30 minutes.
• Love Cast Kit — the kit for 3D hand and foot casts.
• Aqua Pigment — concentrated liquid pigments for colouring the mix.
• Aqua Shield — the water-based additive that makes creations water-resistant.
• Aqua Resin Black — black alpha plaster for design objects.

FAQ

Which plaster is best for DIY objects?

For decorative objects, an alpha plaster like Aqua Resin works best: it is denser and stronger than ordinary plaster, captures fine mould details and gives a porcelain effect. It is non-toxic and water-based.

How much water do I need for plaster?

With Aqua Resin you need 30 g of cold water for every 100 g of powder. Weighing both on a scale is the surest way to get solid pieces.

When can I demould a plaster object?

With Aqua Resin you can demould after 30 minutes. Full drying takes 24 hours, before you colour or protect the piece.

Do I need a release agent with silicone moulds?

No, silicone moulds don't need a release agent: the mould just needs to be clean and dry.

How do I make a plaster object water-resistant?

With Aqua Shield: mix it in instead of water, or brush it on or dip the dry piece. With Aqua Shield in the mix, demoulding takes at least 1 hour.

Can I scent plaster objects?

Yes: just add a few drops of your own essence to the mix. Don't use Aqua Shield on scented plaster, as it blocks the fragrance from spreading.

Ready to make your first plaster object?

Choose a mould, weigh the right amounts and start from an alpha plaster: you'll see the difference from the very first demould. For a truly special gift, the Love Cast Kit is the easiest way to get started with casting.
→ Discover Aqua Resin