Ceramic shell materials for the lost wax method

Advantages of the ceramic shell

• ✓Fast burnout — the shell is burned out in approximately 2 hours, saving a lot of energy compared to plaster and chamotte moulds.
• ✓Lighter weight — the shell is significantly lighter than a plaster or chamotte mould and therefore easier to handle.
• ✓Consistent quality — a smooth, porous shell provides better and more uniform casting quality, with less finishing work.
• ✓Controllable process — with a fixed working process, daily checks and correct storage, the method delivers consistent results.

Option 1 · Traditional 24/7 slurry

The original method and most commonly used in larger foundries. You make your own slurry by mixing a binder (a water-based silica and polymer suspension) with flour. Please note: our binder already contains wetting agent, defoamer, and polymer, so you usually don't need to purchase these separately.

Advantage: the individual components keep for a long time when unmixed (see the date on the packaging), and you have complete control over the composition.

Disadvantage: after mixing, the slurry must be kept in continuous motion, including at night, at weekends and during holidays. If it stands still, it settles, gels and thickens, becoming unusable. Therefore, you need a mixing machine that runs year-round, which is often impractical for smaller users.

Option 2 · Self-prepared with Shellspen

A hybrid approach: you make your own slurry as in option 1, but with a finer flour (325 mesh) and a third component, the Shellspen suspension powder. This means a continuously rotating tank is not needed and periodic mixing is sufficient.

Advantage: full control over the slurry and no continuously rotating tank.

Please note: periodic mixing requires a fixed mixing schedule: half an hour on every day of use, and at least twice a week during periods without use (never more than 7 days unmixed). The Shellspen powder must be mixed in carefully; when using part of a bag, homogenise it thoroughly first.

Option 3 · Self-prepared with xanthan

Here too you make your own slurry with a finer flour (325 mesh), but you use a small amount of xanthan gum in the binder to keep the flour in suspension. The result is a periodically mixed slurry with a simple and economical suspension aid.

Xanthan is not available from us, but it is widely available (online, in supermarkets and at baking supply stores). Use pure, food-grade xanthan gum without additives. The binder and flour you simply obtain from us.

Advantage: full control, no continuously rotating tank, and a cheap, widely available suspension aid.

Please note: the same mixing discipline as option 2 (every day of use, and at least twice a week during periods without use). The formulation uses a different ratio compared to the classic slurry; the manual describes everything step by step.

⚠️ Applies to all options

• Storage of Adbond binder: 5–30 °C, frost-free. Prepared slurry: 15–25 °C, never below 5 °C or above 30 °C. Frozen or overheated binder or slurry is irreparably damaged.
• pH always above 9.5, measured with a pH meter. Below that, the slurry gels irreversibly.
• Mixing time when preparing: at least 4 hours, preferably 24 hours, with a mixer of no more than 2000 revolutions per minute.
• Demineralised water only, and only to top up evaporated water. Thicken with flour, thin with binder.
• Always rinse degreased models with demineralised water; residues of soap or degreaser disturb the slurry.
• Drying indicator is optional and makes the slurry less stable: maximum 100 ml per 25 kg Adbond, not for beginners.

• → Option 1 — Traditional 24/7 slurry: Ceramic shell method manual, continuous mixing (PDF)
• → Option 2 — Self-prepared with Shellspen: Manual for periodically mixed slurry based on Shellspen (PDF)
• → Option 3 — Self-prepared with xanthan: Manual for periodically mixed slurry based on xanthan (PDF)

→Example slurry logbook (Excel)

→Example artwork logbook (Excel)

💡 Tip: Eric W. Stephenson's YouTube channel clearly explains the various steps of the lost wax process with the ceramic shell. Check out LunarburnStudio.

📚 Interesting catalogues: The Investment Casting Institute website provides extensive information about casting defects and wax defects. View Wax & Casting Defects (investmentcasting.org).