Crestafix® B72R
BONDING PASTE

Product info

Crestafix® B72R Bonding Paste

Polyester-Based Core Bedding Compound for Composite Sandwich Construction

Crestafix® B72R is a polyester-based, MEKP-catalysed core bedding compound developed for bonding and bedding cores in composite sandwich structures. Lightweight, highly thixotropic, and non-sagging, it is engineered to provide the controlled elasticity required at the core-to-skin interface, reducing print-through while maintaining structural integrity.

Designed for use in both hand lay-up and vacuum-bagged core installations, Crestafix® B72R delivers reliable gap-filling performance across a wide range of core thicknesses. Its low-shrink formulation ensures consistent laminate quality, even on vertical or complex surfaces.

Key Features & Benefits

Polyester-based core bedding compound

Compatible with GRP laminates and common composite construction methods

Highly thixotropic & non-sagging

Excellent control on vertical and overhead surfaces

Low density & lightweight

Minimises added weight in sandwich structures

Low shrink formulation

Reduces print-through and surface distortion

Wide gap-filling capability

Effective bonding from 1–25 mm (0.04–1.00 in)

Controlled elasticity

Optimised for durable core-to-skin interfaces

Applications

Working Time: ~55 minutes
Recommended Application Temperature: 18–25°C (64–77°F)
Gap Filling Range: 1–25 mm (0.04–1.00 in)
Colour Change: Light blue → off-white (cure indicator)
Shelf Life: 12 months (stored as recommended)

Mechanical & Thermal Properties (Cured)

Tensile Strength: ~18 MPa (2600 psi)
Tensile Modulus: ~1450 MPa (210,000 psi)
Tensile Elongation: ~2%
Lap Shear Strength (GRP): ~5 MPa (substrate failure)
Hardness: ~70 Shore D

Processing & Handling

Crestafix® B72R is supplied pre-accelerated and requires only the addition of catalyst.

Recommended catalyst: 2% Butanox® M50 (MEKP)
Mix thoroughly using a low-shear stirrer to minimise air entrapment
Apply evenly to prepared surfaces; hold bonded components in position until cured

A priming resin should be applied to the core surface prior to bedding for optimum adhesion. Additional pigments or fillers are not recommended, as they may affect cure and mechanical performance.

Packaging & Storage

Packaging: 15 kg Pail
Storage:
Store in original, unopened containers in a dry, well-ventilated area
Recommended storage temperature 2–23°C (36–77°F)
Protect from freezing and direct sunlight

Technical Data Sheet

Crestafix® B72R Bonding Paste

ATL Technical Support
ATL Composites provides core bedding selection advice, laminate system compatibility guidance, and processing support to ensure Crestafix® B72R delivers consistent performance in sandwich composite construction.

frequently asked questions

How does ATL tailor composite systems for different industries?

Every industry has distinct performance, compliance, and manufacturing requirements. ATL’s in-house chemists and engineers develop and refine epoxy systems, adhesives, and core materials to meet the specific demands of marine, defence, aerospace, automotive, industrial, civil, architectural, and sporting applications — ensuring every product delivers optimal strength, efficiency, and durability.

Can ATL customise materials for my project or process?

Yes. ATL offers custom formulation and process engineering support to align material performance with your production requirements — whether infusion, hand lay-up, lamination, bonding, or CNC-routed panel construction. Our technical team collaborates closely with customers to deliver precision-matched resin systems and structural solutions for unique applications.

Are ATL’s composite systems certified for high-performance applications?

Absolutely. ATL operates under an ISO 9001:2015-certified quality management system, with selected materials approved by DNV for use in structural and high-load applications. Every ATL system is manufactured to exacting standards of performance, consistency, and traceability to meet the demands of defence, industrial, and advanced engineering environments.

What makes ATL’s materials suitable for large-scale or structural builds?

ATL’s epoxy systems, structural panels, and composite cores are engineered for high strength-to-weight performance, dimensional stability, and fatigue resistance. These attributes make ATL materials ideal for large composite assemblies, modular structures, and precision-engineered components where long-term strength, weight reduction, and reliability are essential.

Does ATL offer sustainable or bio-based composite options?

Yes. ATL is committed to advancing sustainable composite technology, offering USDA-Certified Bio-Based epoxy systems and environmentally conscious materials that reduce waste, extend service life, and minimise environmental impact. Our ongoing R&D focuses on improving sustainability without compromising structural integrity or mechanical performance.

How can I select the right ATL system for my application?

Choosing the ideal composite system depends on your structure’s design, load requirements, manufacturing process, and environmental exposure. ATL’s in-house engineers and chemists provide tailored advice to ensure the correct combination of resin, core, adhesive, and surface technology for your project.
To discuss your application or request technical guidance, contact ATL’s Technical Team — we’ll help you identify the most effective and efficient composite solution for your build.

latest news

COOSA – Lightweight Strength Driving New Composite Potential

Coosa® and ATL Composites’ Role in Australia’s Composite Evolution Across modern boatbuilding and structural composite construction, the shift away from traditional timber cores is accelerating — driven by performance demands, lifecycle durability, and weight reduction. At the centre of that evolution sits Coosa® Composite Board, globally recognised for its high-performance structural panels. In Australia, that...

Read

Bio Epoxy Solutions for Architectural Timber Craftsmanship

Thor’s Lore Reclaimed Timber. Renewed Purpose. Finished with Bio Epoxy Innovation. Recycled and reclaimed timber is more than a material at Thor’s Hammer — it’s a philosophy. Built on Craft, Heritage, and Sustainability Nestled on the leafy edge of Griffith in Canberra, Thor’s Hammer operates from a purpose-built 11,000-square-metre headquarters housing a skilled team of...

Read

New Life for SOUTH PACIFIC II

South Pacific II, the 75-foot timber motor yacht built by Norman R. Wright & Sons and launched in 1962 as “Beryl May”, returned to the boat builder’s Brisbane headquarters in early 2023 for 18 months of upgrades and refurbishments for its new owner. South Pacific II is considered one of the standout vessels from Norman...

Read

Australian Made and Perfect for High Load Bonding

As epoxy formulators with more than 40 years of experience and in-house technical expertise, ATL Composites has the flexibility to tailor products for specific markets. We are excited to introduce a new high performance adhesive into our TECHNIGLUE range. Techniglue R28 is a thixotropic, toughened system specifically formulated for applications requiring high-strength adhesion. With excellent...

Read

vdL Composites returns to METS in 2024

ATL Composites will exhibit with joint venture partners M.u.H. von der Linden GmbH based in Wesel as vdL Composites GmbH at the 36th METSTRADE Show, running 19 to 21 November 2024 in Amsterdam. The world’s largest B2B marine event, showcasing the products and services of more than 1,540 exhibitors from 53 countries, will occupy 11 halls...

Read

ATL Composites preparing for AWBF 2025

Celebrating 45 years in business in Australia in 2025, ATL Composites will attend the Australian Wooden Boat Festival, 7 to 10 February 2025 as an exhibitor and proud sponsor. ATL Composites has been a long-time supporter of the biannual AWBF and attends each event with the aim of reconnecting with customers and industry. In 2025,...

Read

Edencraft Creative expands with Composites

Since 2022, Josie Maher-Eastman has been the General Manager of her family’s businesses: Edencraft International, Edencraft Marine and Edencraft Creative. Based in Geelong, Victoria, Edencraft International manufactures worldclass fibreglass, offshore fishing boats ranging from 6 to 7.77-metres that can be further customised to meet the needs of recreational and commercial anglers. Linked by brand, Edencraft...

Read

Custom Designed BATHING BEAUTY built to last with WEST SYSTEM Epoxy

The inspired boat builders at Tasmanian Shipwrights & Co have created a one-of-a-kind, totally indulgent, yet highly practical project – a custom-designed and built wooden bathtub. Conceived to take pride of place in the bathroom of a hempcrete home in Franklin Tasmania, the bathtub is the brainchild of homeowner, Dan Rawlins and boatbuilder Nathan O’Neill....

Read

DuFLEX Kit delivers Access and Adventure

Composites are the key to a light-weight, low maintenance “big ute on water” under construction at Noosa Marine. Noosa River will soon welcome a state-of-the-art, Roger Hill-designed hybrid multihull, with all the aesthetic appeal of “Noosa style” and the capacity to accommodate 52 passengers, including 14 wheelchairs. Pitched as a totally inclusive cruise experience, the...

Read

Products Emu Social+engagement Swimming Among The Castings

The Formula for Reef Reconstruction

Rebuilding reefs is a specialist area of conservation, and one that Reef Design Labs has honed to a fine, sculptural art. Reef Design Labs, led by Director and industrial designer, Alex Goad, design, prototype and manufacture unique coastal solutions to restore reefs and protect shorelines. Formed in 2015, the Melbourne-based team of designers, architects, engineers...

Read

Tassie: the Wooden Boat capital of Australia

Tasmania is the epicentre of Australian wooden boat building. As the home of what is considered the world’s finest boat building timbers, Huon Pine, Tassie has a rich heritage of boat building which began in the early years of colonisation and survives to this day. According to the state government, the wooden boat building industry...

Read

Resto brings a Legend Back to Life

A 32-foot Cayzer motor yacht built in 1976 is poised to return to the water as a one-of-a-kind gentleman’s cruiser, thanks to the vision of its owner, the talents of the restoration team at Tasmanian Shipwrights & Co. and WEST SYSTEM Epoxy products. Originally called “Osprey”, the impeccably designed and built wooden boat was chosen...

Read