Still Fixing Your Precast Shutters with Bolts? It May Be Costing Your Factory Production Time.
Discover how shuttering magnets can help precast factories simplify formwork fixing, reduce repetitive manual operations and improve mould changeover flexibility—with RGT International.
In a precast factory, production time is valuable. Yet, when side forms and end shutters are secured using traditional bolts, nuts and external clamps, operators can spend a significant part of mould preparation positioning shutters, aligning fixing points, tightening hardware and removing it again before the next setup.
Multiply these repetitive tasks across multiple moulds, production shifts and working days, and even small delays can become a meaningful operational cost.
There is a more flexible alternative: switchable shuttering magnets.
For suitable precast applications, shuttering magnets can simplify the way steel side forms and end shutters are fixed to the casting bed—reducing repetitive bolt handling and making shutter repositioning easier.
The good news? Your factory may not need to replace its existing steel shutters or overhaul its entire production setup. With the right technical assessment, selected moulds may be converted to magnetic fixing, allowing your team to test the benefits using actual production data before investing in a wider change.
RGT International helps precast manufacturers evaluate this conversion practically: identify suitable moulds, assess the magnet and adapter arrangement, conduct a controlled trial, and measure whether the improvement justifies the investment.
The question is not simply whether magnets can replace bolts. It is whether your current formwork fixing method is helping your factory achieve the productivity it needs.
1. The Challenge with Traditional Bolt-Fixed Formwork
Traditional bolt fixing is a familiar and proven method in precast concrete production. However, it can present operational challenges, particularly when a factory manufactures multiple product sizes or frequently changes its mould configurations.
Common challenges include:
Time-consuming setup: Operators must position and align shutters before tightening the bolts or clamps.
Repetitive manual work: Multiple fixing points require repeated tightening and loosening.
Limited positioning flexibility: Existing holes and brackets may restrict where shutters can be positioned.
Hardware handling: Bolts, nuts and clamps must be stored, handled, inspected and replaced when necessary.
Mould changeover delays: Frequent changes in product dimensions can increase preparation time.
Formwork modifications: Some layout changes may require additional holes, brackets or mechanical adjustments.
The impact varies from factory to factory. A production line manufacturing the same element continuously has different requirements from a plant producing a wide range of precast products.
The objective is not to suggest that bolt fixing is inherently unsuitable. It is to identify whether a different fixing method could improve the factory's actual workflow.
2. What Are Shuttering Magnets?
Shuttering magnets are switchable permanent-magnet systems designed to secure compatible formwork to a suitable steel casting bed.
When activated, the magnet holds against the steel surface. Depending on the system design, a suitable adapter, locating stop or integrated holder can be used to position the shutter and form part of the fixing arrangement.
When the shutter needs to be removed or repositioned, the operator releases the magnet using its designated mechanism.
This can simplify the fixing process by reducing the need to tighten and loosen conventional bolts at every fixing point.
Unlike permanent magnetic attachments, switchable shuttering magnets are designed for repeated activation and release during mould preparation.
3. How RGT International Can Help Convert Existing Formwork
At RGT International, we believe that introducing shuttering magnets should start with understanding the customer's existing production process—not simply selecting a magnet based on its advertised holding force.
Our approach focuses on finding a practical conversion strategy for the factory's equipment and production requirements.
Step 1: Assess the Existing Formwork
We begin by reviewing how the factory currently secures its side forms and end shutters.
The assessment considers:
Casting-bed dimensions and steel thickness
Shutter length, height, thickness and profile
Existing bolt and clamp positions
Product dimensions and mould configurations
Casting and vibration procedures
Frequency of mould changes
Photographs, videos and basic drawings can provide a useful starting point for identifying potential applications.
Step 2: Identify Suitable Applications
Not every mould needs to be converted immediately.
RGT can help identify applications where magnetic fixing may offer the greatest practical benefit, such as moulds requiring frequent shutter repositioning or production lines with repetitive setup and removal operations.
For factories producing different product dimensions, repositionable magnetic fixing may provide greater layout flexibility.
For factories producing standardised elements at high volume, the decision should focus on measurable setup-time savings, operating conditions and conversion costs.
Step 3: Evaluate Magnets and Adapters
A successful conversion may allow the factory to retain its existing steel shutters while changing the fixing method.
Depending on the shutter design, potential arrangements include:
Switchable shuttering magnets with suitable mechanical locating stops
Magnets combined with adjustable shutter adapters
Magnet holders integrated with existing shutter profiles
Magnetic holding combined with positive mechanical locating features
The appropriate arrangement must be established for the actual mould. The complete system must safely resist the loads encountered during casting and vibration.
Important: A magnet's advertised holding-force rating alone does not establish whether it is suitable for a particular shutter. Steel thickness, contact conditions, load direction, shutter geometry and vibration all influence the final selection.
Step 4: Conduct a Controlled Production Trial
Rather than recommending an immediate conversion of an entire production line, RGT can help the factory evaluate a representative mould first.
Record the performance of the existing bolt-fixed system, including:
Number of operators involved
Number of bolts or clamps used
Shutter installation time
Shutter removal time
Total mould changeover time
Alignment issues and rework, where applicable
Then repeat the measurements using the proposed magnetic system.
The trial should also verify shutter stability, dimensional accuracy, concrete leakage, vibration performance and safe magnet release under normal operating conditions.
This provides a practical comparison based on the factory's own results.
4. Bolt Fixing vs. Shuttering Magnets
The comparison does not mean magnets will outperform bolts in every situation. The best solution depends on production frequency, mould design, labour costs, equipment investment and operating conditions.
5. Potential Benefits for Precast Factories
Faster Mould Preparation
Magnetic fixing can reduce repetitive tightening and loosening operations during shutter installation and removal.
The actual time saving depends on the number of fixing points replaced, the shutter design and the existing workflow.
Greater Formwork Flexibility
Where the mould design permits, magnetic fixing points can be repositioned without drilling additional holes in the casting bed. This can be useful when producing precast elements in different dimensions.
Reduced Hardware Handling
A magnetic system can reduce the need to handle separate bolts, nuts and clamps at every fixing point, potentially simplifying day-to-day mould preparation.
Better Use of Production Time
If mould changeovers become shorter, the factory may gain additional time for productive activities.
Whether this results in increased output depends on the factory's production bottlenecks and whether mould preparation is limiting overall production.
A Phased Approach to Modernisation
Factories do not necessarily need to replace all existing formwork at once.
Starting with one suitable mould allows the production team to evaluate technical performance and financial return before making a wider investment.
6. How to Calculate the Return on Investment
RGT recommends calculating the business case using actual factory data rather than relying on generic claims about labour savings.
Annual labour saving
Annual labour savings can be estimated using:
Minutes saved per cycle × annual cycles × labour cost per minute.
For example, if a trial demonstrates a measurable reduction in labour time per mould cycle, that saving can be multiplied by the number of comparable cycles performed annually.
Additional benefits may include reduced hardware replacement, fewer formwork modifications and additional production capacity where mould changeover is a genuine bottleneck.
Payback period
Payback period = Total installed investment ÷ Annual net savings.
The investment should include the magnets, adapters, installation and any necessary modifications. Savings should be calculated carefully to avoid counting the same benefit twice.
RGT can help customers build this comparison once their production data and proposed magnet configuration have been established.
7. Safety and Technical Suitability Come First
Shuttering magnets must be selected and operated as part of an engineered formwork system.
Before implementation, the following factors must be reviewed:
Concrete pressure and shutter geometry
Magnet quantity, spacing and load direction
Casting-bed steel thickness and surface condition
Shutter profile and rigidity
Vibration intensity and direction
Appropriate safety factors and operating procedures
Inspection, operator training and safe release
Rust, paint, concrete residue, oil and uneven contact surfaces can reduce effective magnetic holding performance.
The magnet's rated pull force must not be treated as its allowable working load in every application. The complete arrangement must be validated before production use, including any required mechanical locating or restraint features.
8. Why Work with RGT International?
RGT International supports the precast concrete industry with products and solutions focused on practical manufacturing requirements.
Our approach to shuttering magnets is centred on understanding the customer's existing equipment, evaluating conversion opportunities and helping establish a technically appropriate solution.
We aim to help customers answer four essential questions:
Can the existing steel shutters be retained?
Which moulds are most suitable for magnetic fixing?
What magnet and adapter arrangement is appropriate?
Will the measured productivity and financial benefits justify the investment?
By addressing these questions before a full conversion, factories can make informed decisions based on their actual operating conditions.
9. Is Your Precast Factory Ready to Move from Bolts to Magnets?
If your factory currently uses bolts, nuts or external clamps to secure side forms and end shutters, shuttering magnets may offer an opportunity to simplify mould preparation and improve production flexibility.
The first step is straightforward: review one representative mould, measure the existing setup process and assess whether a magnetic fixing arrangement is suitable.
RGT International can help you evaluate the conversion, identify a suitable trial application and compare the results against your current bolt-fixed system.
Let's Evaluate Your Existing Formwork
Contact RGT International to discuss your current fixing arrangement. Share photographs or drawings of your moulds, explain your production requirements and explore a practical shuttering magnet solution for your precast factory.
RGT International — Practical solutions for more efficient precast concrete manufacturing.
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