Seepage
Traditional steel moulds: Seepage occurs at sharp gable ends where the plates meet the body of the mould.
MCM PU kerb moulds are all-in-one moulds with no separate parts. There is no seepage.
Chipping
Traditional steel moulds: Sharp ends result in chipping.
MCM PU kerb moulds: Edges, including those at the gable ends, have a 2 mm curve radius, reducing chipping. Every exposed face is smooth.
Demoulding time
Traditional steel moulds: Demoulding is cumbersome and time-consuming. Unscrewing the nuts and knocking out the product is cumbersome.
MCM PU kerb moulds: Demoulding is quick and easy. It takes practised workers fewer than 30 seconds to demould.
Mould release oil
Traditional steel moulds: Plant-based mould-release oil is biodegradable and water-based, but it is unfortunately prone to instability when working with steel. Therefore, most manufacturers use petrochemical barrier oils.
MCM PU kerb moulds: Water-based mould-release oils work well with MCM PU moulds. Little or no cleaning between casts is needed.
Cleaning damage
Traditional steel moulds: Concrete adheres to steel. Scrubbing roughens the steel and leaves scratches on the mould that transfer to the product. Surface damage over multiple cleaning cycles worsens the adhesion. Rust between casts increases the need for cleaning.
MCM PU kerb moulds release easily and do not need to be scrubbed. The surface integrity is maintained, yielding smooth, unblemished products throughout the mould’s lifetime.
Blotching and segregation
Traditional steel moulds: Over-vibrating can result in the separation of the fines in the concrete, causing blotching or a shadow effect, with segregation, where the stone shows through the surface.
MCM PU kerb moulds are slightly porous at the micro level. This, along with the mass and thickness of the PU moulds, allows for better vibration transfer throughout the concrete and thus does not cause separation of fines at the surface. The result is an even, unstained concrete product.
Denting
Traditional steel moulds: Steel moulds dent easily. Workers struggle to demould steel moulds, resorting to using mallets and steel hammers to knock out products. This dents the steel moulds. The dents yield inferior products in subsequent casts.
MCM PU kerb moulds are exceptionally robust and do not dent. No force is needed for demoulding.
Cold sensitivity
Traditional steel moulds: In wintry weather, steel cools the concrete, making it cure more slowly and slowing down production. Concrete also sticks to steel more tenaciously when it is cold due to the reduced viscosity of mould-release oil. Both factors work together to slow down the curing process.
MCM PU kerb moulds provide insulation against the cold, reducing curing time. (It is sometimes possible to cast two batches in one day.) MCM PU moulds do not stick during demoulding.
End-product consistency
Traditional steel moulds: End-products become worse over time as moulds lose integrity, resulting in imperfect products that exceed specified tolerances within various parameters.
MCM PU kerb moulds consistently cast perfect products. Their extended lifespan results from thorough and continuous PU system research and mould-making practices developed over 30 years. Some moulds supplied 15 years ago are still in daily use today.