Manufacturer source check

Checked against TDS v1.0, 24 October 2024 and the manufacturer page, which marks this product discontinued. Confirm a replacement and its own specifications.

Unresolved source conflict: TDS uses section −40°C to +90°C; TDS technical table −40°C to +100°C; retail table −40°C to 150°C. The TDS separately permits 180°C for 20 minutes during coating processes. Confirm the required rating with Selleys.

TDS and retail features: ±20%; retail table: ±25%. Do not design for ±25% without manufacturer confirmation. TDS v1.0: approximately 15 minutes; retail table: 30 minutes. Confirm the matching label. The TDS v1.0 (24 October 2024) gives approximately 2.5 mm per 24 hours. The retail page lists 5–7 days; full cure depends on bead depth and conditions. TDS: mineral turps before cure, mechanical removal after cure. Retail table: damp cloth. Follow the matching label and check substrate compatibility.

What is Selleys 670 Fast Grab, and where should you use it?

Selleys 670 Fast Grab is a high strength elastic adhesive sealant with fast strength build-up, based on advanced hybrid technology and designed for bonding and sealing applications where immediate grab is required. It is a silyl-modified polymer with high tensile strength and very broad primerless adhesion on most building materials, wet and dry, with excellent resistance to ageing and weathering — suitable for internal and external use. It contains no solvents and no isocyanates.

The manufacturer quotes initial grab up to 150 kg/m², but bonded elements may still require support during cure. This is not a safe working-load specification for a particular joint.

Technical specification

Property	Typical result
Technology	Silyl-modified polymer
Colour	Black, grey and white
Density	1.49
Application temperature	5–40°C
Skin time	Approx. 15 minutes
Cure rate	Approx. 2.5mm per 24 hours
Tensile strength (ISO 37, DIN 53504)	Approx. 2.8 N/mm²
Shore A hardness (DIN 53505)	Approx. 58
Elongation at break (ISO 37, DIN 53504)	Approx. 350%
Modulus at 100% elongation (ISO 37, DIN 53504)	Approx. 1.5 N/mm²
Movement capability (EN 15651/1; ISO 11600)	±20%
Service temperature	Unresolved source conflict: TDS uses section −40°C to +90°C; TDS technical table −40°C to +100°C; retail table −40°C to 150°C. The TDS separately permits 180°C for 20 minutes during coating processes. Confirm the required rating with Selleys.
Initial grab	Up to 150kg per m²
VOC	Low VOC — meets GBCA VOC content requirement <50 g/L
Packaging	290ml cartridge in black, grey and white

These are indicative data only, not intended for the preparation of specifications.

What the key numbers mean in practice

Support requirements depend on the installation. Follow the TDS and assess the materials, load and cure conditions; do not convert the initial-grab headline into a guarantee that a panel can be left unsupported.

The 15-minute skin time with 10 minutes of adjustability defines the working sequence. Position the part, adjust it within ten minutes, and finish all tooling within the skin time. After that, tooling tears the surface rather than smoothing it.

Shore A hardness of about 58 with a modulus at 100% elongation of about 1.5 N/mm² makes this a firm sealant, not a soft one. That firmness is what carries load; the trade-off is that it transfers more stress into the substrate than a soft, low-modulus facade sealant would. Combined with 350% elongation and ±20% movement capability, it suits joints that need strength and moderate movement, rather than joints that move a great deal.

The cure rate of about 2.5mm per 24 hours is what sets the schedule. The system is moisture-cured, so the manufacturer's instruction is to permit sufficient exposure to air. A bead squeezed between two impermeable faces cures far more slowly than the same bead in an open joint.

Temperature limits need manufacturer confirmation. Unresolved source conflict: TDS uses section −40°C to +90°C; TDS technical table −40°C to +100°C; retail table −40°C to 150°C. The TDS separately permits 180°C for 20 minutes during coating processes. Confirm the required rating with Selleys.

Where to use it

The manufacturer describes it as ideal for bonding and sealing in industrial and construction work where a tough flexible rubber joint or a powerful elastic adhesive is required. Its listed uses are:

• Automotive assembly
• Transportation assembly — coach, caravan, refrigerated vehicles, containers
• Air conditioning and ventilation
• Applications where a tough flexible rubber joint or a powerful elastic adhesive is required
• Short-time high temperature (180°C) applications such as industrial coating processes

It bonds and seals at the same time, gives no shrinkage during curing, and is colour stable — non-yellowing and non-chalking. See also Selleys 650 FC and the rest of the 600 Series.

Joint design and coverage

If using it to fill expansion joints:

• Minimum joint width and depth is 5mm.
• For joint widths up to 12mm, use a width to depth ratio of 1:1.
• The optimum width to depth ratio for joint widths greater than 12mm is 2:1.
• Always install a suitable diameter backing rod — polyethylene or polyurethane foam — to control sealant depth and ensure free movement.
• Wider joints can accommodate more total movement than narrow joints.
• The sealant must adhere to the sides of the joints only and NOT to the back, so that it is free to stretch.

For general applications, a cartridge will cover approximately 32 metres for a 3mm bead. For joint filling:

Joint width (mm)	Joint depth (mm)	Litres per lineal metre	Metres of coverage
6	6	0.036	8
8	8	0.064	4.5
10	10	0.100	2.9
12	6	0.072	4

Compare the 10 × 10 row with the 12 × 6 row: the wider joint at the correct 2:1 ratio is both a better-performing joint and about 40% more economical per metre. Joint geometry is worth getting right before you order.

How to apply it

The directions below should only be used as a guide — the installer should apply all Australian Standards, BCA/NZBC requirements, and best practices when installing.

1. Ensure the surface is clean, dry and free from oil, grease, release agents, dust and loose material. It is advisable to carry out preliminary adhesion tests on the substrate.
2. Cut the end of the cartridge, attach the plastic nozzle, and cut it at an angle according to the desired bead thickness and profile.
3. Fit the cartridge into a cartridge gun and extrude the adhesive or sealant carefully, preventing air entrapment.
4. For joint sealing, extrude the sealant so that it is in full contact with the sides of the joint, avoiding overlapping, then smooth with a spatula, forcing the sealant into the joint for better contact with the sides.
5. Carry out all tooling and finishing within the skin time.
6. Support bonded elements as required during the curing period.

The optimum application temperature for both substrate and sealant is between 5°C and 40°C.

On priming: 670 Fast Grab generally has good adhesion without priming to the common building materials indicated. For some plastics and pre-painted surfaces, priming may be required, and a pre-test to ensure suitable adhesion is recommended.

Painting

670 Fast Grab can be overpainted with water-based paint. Apply a water-based primer before applying a solvent-based paint. To maximise durability in outdoor applications, paint with a suitable exterior paint.

One caution the manufacturer raises is worth heeding: the hardness and film thickness of the paint may impair the elasticity of the sealant and lead to cracking of the paint film. A thick, hard coating over a joint that moves will crack along the bead — that is the paint failing, not the sealant.

Limitations — where it should NOT be used

• Not recommended for continuous submersion or below water line use. The page also states it is not suitable for aquariums or underwater applications.
• Do not apply in the presence of curing silicone sealants, as cure may be affected.
• Avoid contact with alcohol and other solvent cleaners during cure, as cure will be affected.
• Do not use for structural glazing.
• May affect drying of alkyd and oil-based paints unless primed with a water-based primer.
• Will not adhere to PE, PP or PTFE. Test other plastics and rubber first.
• Movement capability is ±20% — do not use it on joints designed for more.

The silicone interference warning matters on a busy site. If another trade is running silicone nearby in an enclosed space, the vapour can stop this product curing properly, and the failure is invisible until the joint is loaded. Sequence the work or ventilate the area.

Clean up and storage

Spills and tools can be cleaned up with mineral turps before the product cures. Cured product can only be removed mechanically.

Store unopened cartridges below 30°C in a cool dry place away from direct sunlight; unopened, they keep for 12 months from the date of manufacture. Once opened, packs should be used up within a relatively short time. Opened cartridges will skin and form a lump near the opening — discard any lumps or skin, and the remaining product can be used.

Hazard classification

Classified as hazardous under Safe Work Australia GHS 7, with the signal word Warning.

• Eye irritation — Category 2A. H319: causes serious eye irritation.

It is not classified as Dangerous Goods under the Australian Code for the Transport of Dangerous Goods by Road & Rail, or under New Zealand NZS5433.

What is in it

Chemical entity	CAS number	Proportion (w/w)
N-[3-(Trimethoxysilyl)propyl]ethylenediamine	1760-24-3	<1%
Decanedioic acid, bis(2,2,6,6-tetramethyl-4-piperidinyl) ester	52829-07-9	<1%
Ingredients determined to be non-hazardous or below reporting limits	—	Balance

This is a short list for a construction adhesive, and that is the point of the chemistry. The page above notes that 670 Fast Grab contains no solvents and no isocyanates; the classification is the evidence for it. A single hazard class, at Category 2A, with both declared components under 1% — compare that with a polyurethane stablemate such as Flexiseal FC, which is classified hazardous specifically because it contains isocyanates. If the choice between silyl-modified polymer and polyurethane is open on your job, this is the part of the comparison that does not appear in the performance table.

The two declared entities are both present in trace amounts, and their chemical classes suggest what they are doing rather than the SDS saying so directly. Aminosilanes of this type are the component class normally used as adhesion promoters in silyl-modified polymer sealants, which would connect the first entry to the very broad primerless adhesion the product is sold on. The second is a hindered amine of the class used as a light stabiliser, which is the kind of additive that underwrites a non-yellowing, non-chalking claim over years of UV exposure. Treat both as reasonable inference from the chemistry, not as sourced statements.

The eye classification is the one to act on. Category 2A is serious eye irritation, not eye damage — it is reversible — but the product is used in exactly the postures that put an eye in the line of a bead: cladding, coach and caravan assembly, air conditioning and ventilation work, much of it overhead or at shoulder height with the cartridge above you. A nozzle that unblocks suddenly under gun pressure travels up, not down. Safety glasses are cheap insurance against a fifteen-minute eye flush on a job site.

The other exposure route is tooling. The instruction on the page is to smooth the bead with a spatula and to finish all tooling within the 15-minute skin time, which is a working rhythm that invites a bare finger when the spatula is out of reach. Uncured sealant on a finger reaches an eye later, which is why the SDS asks for hands, face and exposed skin to be washed thoroughly after handling rather than at the end of the day.

Protection

• Eye protection — safety glasses, and eye or face protection where you are extruding above shoulder height.
• Gloves — nitrile rubber is indicated as suitable for intermittent contact; glove construction and site conditions vary, so make the final assessment yourself.
• Clothing — overalls and safety shoes are specified for the workplace uses this product is sold into.
• Ventilation — natural ventilation is adequate in normal use; keep the storage area cool, dry and well ventilated.
• Wash hands, face and all exposed skin thoroughly after handling, and before smoking, eating, drinking or using the toilet. Wash contaminated clothing and protective equipment before storing or re-using it.
• Store away from foodstuffs, incompatible materials and sources of heat or ignition, with the container closed and upright.

First aid

Exposure	What to do
Eyes	Hold the eyelids apart and flush the eyes continuously with running water. Keep flushing until the Poisons Information Centre or a doctor tells you to stop, or for at least 15 minutes, then get to a doctor or hospital. Remove contact lenses if present and easy to do, and keep rinsing.
Skin	Remove contaminated clothing and flush the skin and hair with running water. If swelling, redness, blistering or irritation occurs, seek medical assistance.
Inhalation	Move the person to fresh air without becoming a casualty yourself. Remove contaminated clothing and loosen the rest, let them settle into the most comfortable position and keep them warm and at rest until fully recovered. Seek medical advice if effects persist.
Swallowed	Rinse the mouth with water. Do not induce vomiting. Give a glass of water to drink. Never give anything by mouth to an unconscious person. If vomiting occurs, give further water and seek medical advice.

If poisoning occurs, contact a doctor or the Poisons Information Centre — 131 126 in Australia, 0800 764 766 in New Zealand — with the container to hand. Selleys emergency line: 1800 220 770 in Australia, 0800 220 770 in New Zealand.

Common questions about Selleys 670 Fast Grab

How much weight will it hold immediately?

Fast grab up to 150kg per m². Bonded elements may still require additional holding or support during the curing period.

How long can I reposition a part?

It is adjustable for 10 minutes, with a skin time of approximately 15 minutes.

How fast does it cure through?

Approximately 2.5mm per 24 hours. It is moisture-cured, so permit sufficient exposure to air.

How much joint movement will it take?

±20%, tested to EN 15651/1 and ISO 11600.

How hot can it get?

Service temperature is −40°C to +100°C, with short term exposure at 180°C — specifically up to 180°C for 20 minutes during powder and thermal coating processes.

Can I apply it to a damp surface?

It offers broad primerless adhesion on most building materials, wet and dry. Preliminary adhesion tests on your substrate are advisable.

Do I need a primer?

Generally not, but priming may be required for some plastics and pre-painted surfaces. Pre-test.

Can I paint over it?

Yes, with water-based paint. Apply a water-based primer before a solvent-based paint. Use a suitable exterior paint outdoors, and avoid thick, hard coatings, which can crack over a moving joint.

Will it stick to plastic?

Not to PE, PP or PTFE. Test other plastics and rubber first.

Can it be submerged?

No — not recommended for continuous submersion or below water line use, and not for aquariums.

Can I use it for structural glazing?

No.

Why is my bead not curing?

Check whether silicone is curing nearby, or whether the bead has contacted alcohol or solvent cleaners — both affect the cure. Also confirm the bead has enough exposure to air, since the system is moisture-cured.

What joint dimensions should I use?

Minimum 5mm width and depth. Up to 12mm wide, use 1:1 width to depth; above 12mm, use 2:1, with a backing rod to control depth.

What sizes and colours are available?

A 290ml cartridge in black, grey and white.

How do I clean up?

Mineral turps before the product cures. Cured product can only be removed mechanically.