Shellspen, Suspension powder

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Shellspen

Shellspen, Suspension powder

Shellspen suspension powder keeps solid particles in ceramic slurries evenly distributed, eliminating the need for constant stirring. This makes the process of making ceramic molds more efficient and convenient. Read more

€110,11 Incl. BTW

SKU: A11995

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250 gram bag for 25 kg flour or 50 kg slurry

€110,11

€4,40/kg

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Shellspen suspension powder keeps solid particles in ceramic slurries evenly distributed, eliminating the need for constant stirring. This makes the process of making ceramic molds more efficient and convenient.

Shellspen suspension powder

Shellspen is a suspension powder specifically developed for use in ceramic slurries for the lost wax method. By adding Shellspen to your slurry, the solid particles (flour) remain in suspension much longer, meaning continuous stirring is no longer necessary. Periodic mixing suffices — a significant advantage for smaller foundries and sporadic users.

Shellspen is part of Option 3 in our approach to preparing a ceramic slurry: self-composed, full control, no continuously running mixing machine. See the Ceramic Shell Materials collection page for an overview of all options.

What makes this formulation different?

A traditional ceramic slurry must be kept in continuous motion. If the slurry remains unmixed for too long, it will settle, gel, and harden — often becoming unusable. With Shellspen, that's a thing of the past. Two aspects deliberately deviate from the classic recipe:

✓Finer flour — 325 mesh fused silica flour is used instead of the usual 120 or 200 mesh. This finer flour behaves differently in terms of viscosity and sedimentation.
✓Shellspen as a suspension aid — the powder is first dry-mixed with the flour and then introduced into the binder along with the flour. This is what makes periodic mixing possible.

Consider this formulation as a distinct recipe — not simply as "the same slurry that you stir less frequently".

Properties

✓Improved stability — keeps solid particles in suspension, ensuring the slurry remains homogeneous without continuous stirring.
✓Ease of use — periodic mixing is sufficient; no continuously running mixing machine.
✓Long shelf life — a slurry made with Shellspen can last up to six months, provided it's briefly mixed weekly.
✓Suitable for bronze and aluminum — the slurry can be used for both metals. For aluminum, we recommend Clayrac (aluminum silicate) as stucco, as a full fused silica shell can be more difficult to remove.

Quantity and basic ratio

1 bag of Shellspen (250 g) is sufficient for 25 kg of 325 mesh fused silica flour — or for a batch of 25 kg Adbond + 25 kg flour (1:1 ratio by weight).

These quantities yield approximately 27 to 33 liters of slurry. Use a vessel of at least 30 liters, preferably 30–40 liters, to ensure sufficient headspace during mixing.

Start deliberately on the thin side (1:1). Thickening by adding flour is much simpler and more predictable than thinning out a too-thick slurry.

Step-by-step: preparing the slurry

Work with a powerful mixer, such as a cement drill with a mixing paddle. Follow the steps in order:

Take 25 kg of 325 mesh fused silica flour (or 200 mesh if preferred).
Dry-mix the entire contents of one bag of Shellspen with the flour. You first create a dry mixture of flour and Shellspen.
Pour 25 kg of Adbond (approx. 21 liters) into a vessel large enough for 30 liters of slurry plus space for mixing.
Add the dry mixture (flour + Shellspen) through a sieve to the Adbond binder.
Mix until everything is homogeneous — approximately 15 to 30 minutes. Check every 5 minutes for any dry particles at the bottom.
Let the slurry rest for at least 1 hour, preferably overnight.
Sieve the slurry again for best results, ensuring no lumps remain.
The slurry is ready. Always mix thoroughly before use and close the vessel when storing.

⚠️ Pay attention to the vessel volume during mixing. During the addition and mixing of the flour, the slurry temporarily requires more volume than the final volume, as the flour has not yet settled and de-aerated. For 27–33 liters of final slurry, calculate for a vessel of at least 30–40 liters.

Advantage & point of attention

Advantage: full control over slurry composition, long shelf life of individual components, and no continuous mixing required.

Point of attention: the Shellspen powder must be mixed in carefully and evenly. When using a partial bag, the powder must first be thoroughly homogenized before weighing out a portion.

Documentation

→ Manual for periodically mixed slurry based on Shellspen (PDF)

Safety Information

Safety Pictograms	Safety Data Sheets (SDS)

More information about H and P statements: UK HSE &ECHA

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FAQs

What is the delivery time of my order?

Orders placed and paid for on business days will be shipped on the same day in most cases. Orders received on weekends will be processed on the next business day.

We always do our best to ship orders as quickly as possible, but actual shipping times may vary due to high volume, stock availability, or carrier circumstances.

Delivery time depends on the destination country and the carrier. Below is a general indication:

Netherlands: usually within 1 business day
Belgium & Germany: typically within 1–2 business days
Other countries: depends on the destination and the local carrier

Please note: these are guidelines, not guarantees. The final delivery time may differ due to factors beyond our control, such as sorting center delays, public holidays, or exceptionally high volume.

What is the return policy?

We offer a 30-day return policy as an added service. If you'd like to return an item or if there's something wrong with your order, please email us at info@siliconesandmore.com with your name and order number within 30 days of delivery. We'll help you quickly. The full terms and conditions can be found on our returns page.

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Once your order has been processed and shipped, you'll receive a track and trace code by email, allowing you to easily track your package. Please note that it can sometimes take up to 24 hours after processing for the track and trace to be active.

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