For bonding precast concrete, natural stone, and heavy metal fixtures on vertical or overhead surfaces where sagging would ruin the assembly, Megapoxy 254 is a non-sag epoxy adhesive paste that holds its position without slipping. Formulated to cure even under cold and damp conditions, this solvent-free, white paste creates high-strength permanent bonds that resist water immersion and chemical exposure.
Non-staining paste with high structural strength
Megapoxy 254 is a two-part epoxy paste with a creamy, easily blended texture. It is formulated to be free of volatile organic compounds (Nil VOC) and, when mixed thoroughly at the correct ratio, will not stain or discolour white or light-coloured marble, natural stones, or ceramics. With a compressive strength of 70 MPa and a concrete bond strength exceeding 3 MPa, it creates structural joints that are mechanically stronger than the concrete substrate itself, making it reliable for grouting bolts, repairing concrete pipes, and flush-filling countersunk screws in fibre cement sheets.
Numbers that matter
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1:1 mix ratio — Simple volumetric equal-part mix ratio (1 Part A to 1 Part B) to reduce batching errors on site.
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45-minute work time (at 25°C) — Practical application and alignment window before the adhesive begins to set.
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24-hour cure (at 25°C) — Minimum cure time before the joint can be loaded; cures in 48 hours at 15°C and 12 hours at 35°C.
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70 MPa compressive strength (ASTM D695-23) — Structural-grade load-bearing capacity for columns, stairs, and concrete repairs.
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20 MPa tensile bond strength on steel (ASTM D897-08) — High-tenacity adhesion for heavy metal-to-metal and metal-to-concrete structural connections.
Where to use it
Megapoxy 254 is suitable for structural bonding, filling, and repair tasks across several substrates:
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Bonding: Precast concrete articles, metal to metal, metal to concrete, natural stones, bricks, ceramics, and compressed cement sheet.
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Filling and repair: Concrete pipes, concrete tanks, fibreglass articles, concrete floors, concrete stairs, concrete columns, insitu formed concrete, and flush-filling countersunk screws in fibre cement sheet.
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Grouting: Anchoring and securing bolts into concrete and masonry.
Limitations
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Mixing precision: Inaccuracies and poor mixing will lower the physical properties of the cured system. If the mixing error is large enough, the system may fail to cure satisfactorily and discolour as it ages.
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Coated surfaces: Bonding directly to painted or galvanised surfaces results in inferior bond strength. All coatings must be removed to expose the bare, prepared substrate.
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Metal preparation: Wire brushing is not satisfactory and provides minimal adhesion only. Metals must be grit blasted or mechanically abraded to a clean, bright finish.
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Temperature floor: Do not apply the product at temperatures below 10°C.
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Thermal limits: Safe for continuous service up to a maximum operating temperature of 70°C.
Surface preparation
To ensure structural adhesion, substrates must be prepared strictly in accordance with the following requirements:
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Concrete: Must be free from grease and oil. Remove surface laitance by scabbling, grit blasting, or grinding. If mechanical preparation is not possible, acid etch using a 1:1 mix of hydrochloric acid and water spread at 0.5 litres per square metre. Let react for 10 minutes, scrub thoroughly with a stiff broom, wash down, and allow to dry for 24 hours. Concrete should be surface dry for maximum adhesion.
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Metal surfaces: Grit blast to AS CK 9.4 - 1964 Class 3 finish. If grit blasting is not possible, mechanically abrade to a bright metal surface, then degrease by flooding the area with an industrial grade degreaser.
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Coated concrete: Remove paint using a flame-cleaning or scutching tool, followed by diamond grinding or scabbling.
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Coated metals: Remove paint or galvanising using a high-quality paint stripper, followed by grit blasting or grinding to a bright metal finish.
Clean-up
Clean all mixing tools and application implements immediately after use with Megapoxy Thinners. Wear disposable rubber gloves during mixing and application to maintain proper hygiene.