The solidification of the KUPI ceramic casting powder begins after 30–60 minutes , but complete hardening depends on various factors.

Drying times at a glance:

✔ Surface dry: after approx. 1 hour – the object can be carefully demolded.
✔ Touch dry: after approx. 12 hours – ideal for careful further processing.
✔ Completely cured: after approx. 24–48 hours , depending on the size and thickness of the casting.

💡 Tip: If necessary, the curing process can be accelerated in the oven (max. 190°C for 25-30 minutes) .

Air bubbles usually occur due to incorrect mixing or pouring of the casting powder. But don't worry – with the right techniques, you can achieve bubble-free castings !

Common causes & solutions:

✔ Stirring too vigorously? → Stir slowly and evenly , using a spatula, spoon, whisk, or similar.
✔ Added the powder to the water too quickly? → Sprinkle the casting powder slowly , don't pour it in all at once.
✔ Is air trapped in the mold? → Gently tap the mold on the table or shake it gently to release any air bubbles.
✔ Are fine details in the mold affected? → First apply a thin layer with a brush , then pour in the rest.

💡 Tip: If small bubbles do appear, you can lightly sand the surface of your casting after it has hardened.

No, casting powder is not naturally waterproof as it absorbs moisture and can therefore become brittle or soft over time.

How to make your KUPI casting powder waterproof:

✔ Clear varnish or acrylic sealant – protects against moisture and preserves the surface.
✔ Epoxy resin coating – for a water and shock resistant seal.
✔ Concrete glaze or outdoor sealer – ideal for weatherproof outdoor decorations.
✔ Impregnating agent for stone & concrete – protects the material from water absorption.

💡 Tip: Do not seal your casting until it has completely cured (at least 24 hours).

No, KUPI ceramic casting powder remains brilliant white even after drying and does not gray. Thanks to its high-quality formula, it retains its color and ensures consistent, flawless results.

Why does KUPI casting powder stay white?

✔ Highly purified ingredients – free from impurities that could cause graying.
✔ Optimal water absorption – no excess that can cause color changes.
✔ Even drying – no staining or unwanted color differences.

💡 Tip: Store your casting powder in a dry and airtight container to maintain its quality over time. If you want to further protect your casting, you can treat it with clear varnish or a sealant .

Yes, leftover dry KUPI ceramic casting powder can be safely reused as long as it is stored in a dry, airtight and cool place.

How to store casting powder properly for reuse:

✔ Store in an airtight container or bag to avoid moisture.
✔ Store in a dry and cool place , away from high humidity (e.g. not in the bathroom).
✔ Sift briefly before reusing if small lumps have formed.

💡 Important: If the powder has become moist or clumped, the processing quality may suffer - in this case, it is better not to use it anymore.

Our KUPI casting powder is not completely fireproof , but can withstand temperatures of up to approx. 200°C for about 10 minutes .

It's ideal for decorative objects, bowls, or tealight candle holders . However, direct contact with flames or prolonged exposure to high heat (e.g., near fireplaces or fire pits) should be avoided.

Please note:

All ceramic or gypsum-based casting powders – including well-known products such as Keraflott, Raysin or Keracraft – are not suitable for permanent use at high temperatures or direct contact with fire.

💡 Of course, you can still create beautiful candle holders with KUPI casting powder . However, for liability reasons , we would like to point out that we cannot guarantee heat resistance or safety in direct contact with flames .

This is generally not a problem for tea lights or those with a short burning time – however, we generally recommend using your creations on a fireproof surface and never leaving them burning unattended.