Moulding, Casting & Artificial Stone · Choose a Material / Solution
Mould rubber and release system selection
Tooling rubber and release chemistry are one decision, not two: the rubber you choose changes which release makes sense, and a release that suits one cast material can ruin the surface of another. Answer three questions about the job and this page narrows the families worth quoting — then take the final call from the data sheets and a test mould.
Three questions about the job
The answer narrows families worth quoting. It never names a single product and never predicts mould life.
Answer all three to see candidate families. Partial answers produce no output on purpose — a rubber recommendation without a cast material would be guesswork.
Use this when
- You are quoting a new mould and do not yet know which rubber family fits the job.
- A rubber is working but the cycle count is uneconomic and you want to compare families.
- You changed cast material and the old release is now marking, sticking or building up.
- You are moving from block pouring to brush-on or glove moulds and the rheology has to change.
How this works
- 1. Tell the page what you cast, roughly how many pulls the mould has to give, and how the mould is built.
- 2. It returns candidate rubber families with the trade-off each one carries — never a single 'best'.
- 3. It returns release approaches that are commonly compatible with that pairing, and flags the ones that are known to cause problems.
- 4. You confirm the pairing against the supplier data sheets you hold and a test mould before committing.
What this page does not determine
- It does not select a specific product, hardness, viscosity or cure speed for your part.
- It does not predict how many pulls a mould will give — cycle life depends on geometry, demould technique, cast chemistry and care.
- It does not certify chemical compatibility between any release and any cast material; that is a data-sheet and test-patch question.
- Nothing on this page is a structural, strength, durability or code-compliance statement. Cast stone, precast and GFRC elements that carry load, span, or form part of a building envelope are engineering work and belong with a qualified engineer.
- Verify on a test patch or a sacrificial part before you change anything on a production run.
Relevant Allzone products
These are catalogue identities relevant to investigate. A listing here is not a recommendation to use the material in any process, and it is not a suitability, performance or compliance claim.
- Tin Cure Silicone Mould RubberCondensation-cure RTV silicone. Not sensitive to the contaminants that inhibit addition-cure systems; shrinks slightly over its life.
- Platinum Cure Silicone RubberAddition-cure RTV silicone with very low shrinkage — and the system that inhibition problems almost always involve.
- Polyurethane Mould RubberTear-resistant tooling rubber often used for concrete and cast stone production moulds; moisture sensitive while curing.
- Liquid Latex Mould RubberBrush-applied, many thin coats, long build time; a low-cost route for plaster and concrete reproduction moulds.
- Silicone Thixotropic AdditiveThickens pourable silicone for brush-on and glove moulds on vertical surfaces.
- Polyurethane Rubber SoftenerModifies the hardness of a polyurethane tooling rubber within the supplier's stated limits.
- Casting Resin Mould Release AgentRelease chemistry intended for resin casting into rubber and rigid tooling.
- Mould Release WaxPaste wax barrier used on rigid tooling and on porous masters; builds up over repeated cycles.
- PVA Release AgentFilm-forming barrier release; water soluble, so it washes off the part rather than staying on it.
- Concrete Form Release AgentRelease chemistry for concrete and cast stone against forms and production moulds.
- Mould SealerSeals porous masters and moulds so a release agent can sit on a surface instead of soaking into it.
Where this comes from, and what it cannot tell you
Supplier technical data sheets for the seven live tooling rubbers and five live release identities
Supports: Cure system, general handling behaviour and stated compatibility limits by family.
Limitation: Families generalise. Two products in the same family can behave differently, and only the sheet for the product you buy is authoritative.
Manufacturer-specific · Always read the current revision
Allzone catalogue specification data, Moulding & Casting shelf
Supports: Which rubber and release identities are actually available to quote.
Limitation: Availability is not suitability.
Canada · Maintained with the live catalogue
Related knowledge & tools
- Casting defect troubleshootingWhen the mould or release you already have is producing a visible failure.
- Precast concrete form release agent selectionThe concrete-form side of release selection, covered in depth.
- Cast stone batch and filler loading calculatorTurn the chosen system into purchase quantities.
- Moulding, Casting & Artificial Stone KnowledgeSolve a problem, choose a system, calculate a batch.