What is Selleys No More Cracks Wood Filler Interior, and where should you use it?

Selleys No More Cracks Wood Filler Interior is a ready to use filler that gives a superior, durable finish on interior timber. It is a pine coloured paste with excellent adhesion, it is stainable and paintable, and once dry it can be nailed or planed as well as sanded.

Being both stainable and paintable is the point of difference worth understanding before you buy. Most fillers assume a painted finish, which hides everything. This one is intended to work under a clear or stained finish too — which is where filler choice actually matters, because a stained repair either blends into the grain or announces itself. If your timber is going to be painted, almost any interior filler will do; if it is going to be stained and varnished, the filler has to take colour.

Technical specification

Property	Typical result
Appearance	Pine coloured paste
Drying time at 25°C — 1 mm	1–2 hours
Drying time at 25°C — 2 mm	2–3 hours
Packaging	270 g tub
Use	All interior timber
Clean up	Water, before the filler dries

These are indicative data from the product's technical data sheet only, and are not intended for the preparation of specifications.

What the drying times mean in practice

The two published figures — 1–2 hours at 1 mm and 2–3 hours at 2 mm, both at 25°C — tell you something useful about how this filler behaves. Doubling the depth roughly doubles the wait. That is a shallow-fill product, timed for the kind of repair it is designed for: nail holes, small splits, dents and surface damage in interior joinery.

Both figures assume 25°C, and Selleys attaches humidity as the variable to watch — the instruction is to allow 2–3 hours "depending on humidity". In a cool or damp room, allow longer. Sanding a filler that is not yet dry drags the surface and tears the repair out of the hole instead of levelling it, and you end up filling the same spot twice.

Because the times are measured in hours rather than days, filling and finishing a set of interior doors, architraves or shelving is a same-day job: fill in the morning, sand and apply the second coat after lunch, undercoat late in the day.

Where to use it

It is for all interior timber — doors, skirtings, architraves, window reveals, furniture, shelving and interior joinery generally. It has excellent adhesion, it can be nailed or planed once dry, and it sands easily.

Being able to plane it is worth noting. On a repair that has to follow a moulded profile or sit flush along a long edge, a block plane or file takes material off far faster and flatter than sandpaper does.

For exterior timber, use No More Cracks Exterior Wood Filler, which is formulated for weather exposure. Selleys also has a range of traditional wood putty products, and advice on splits in wood and filling screw holes. The full filler range is on the wall filler page.

How to apply it

1. Make sure the surface is clean and dry, with no loose or powdery material.
2. Use a filling blade or scraper to press the filler firmly in, and scrape off the excess to minimise sanding. On timber this matters more than on plaster: heavy sanding across a grained surface scratches the timber around the repair, and those scratches show under stain.
3. Allow 2–3 hours to dry, depending on humidity, then sand with fine sandpaper.
4. For a perfect finish, apply another thin coat of filler, allow it to dry, then sand lightly with very fine sandpaper.
5. For best results, apply an undercoat before your top coat.

The two-coat method is worth the extra couple of hours on visible joinery. The first coat fills the void; it also shrinks slightly into the hole as it dries, which is why a single-coat repair often reads as a shallow dimple once painted. The second thin coat levels that out.

Staining and colour matching

This is where the product earns its keep, and where Selleys gives the most specific advice.

Start with a light application of stain. The tone can then be progressively darkened by applying more stain until you reach the tone you want. This only works in one direction — you can add colour, but taking it back off means sanding out the repair and starting again, so err light.

Test first, if you can, on an inconspicuous area or an off-cut to determine how much staining is needed for a perfect colour match. A scrap of the same timber with a patch of filler in it, stained alongside the real repair, costs ten minutes and tells you what the finished result will look like.

The final colour is not achieved until the varnish is applied. This is the point most people get wrong. Varnish deepens and warms both the timber and the filler, and it does not change them by the same amount. A match that looks slightly pale before varnishing may be right afterwards, and a match that looks perfect dry may shift once the finish goes on. Judge the match on a varnished sample, not a bare one.

Limitations — where this filler should not be used

• Do not use below 5°C.
• Where movement occurs, use Selleys No More Gaps. A rigid filler in a moving joint cracks along the joint line. In interior joinery the common case is the gap between an architrave and the wall, or between a skirting board and the floor — those are joints between separate components, not defects in a single piece of timber, and they move.
• It is an interior product. For exterior timber, use the exterior version.

The test to apply is simple: is the damage in a piece of timber, or between two pieces? Filler belongs in the first case, a flexible sealant in the second.

Clean up and storage

Clean up: clean tools and hands with water before the filler dries. Once dry, removal is mechanical.

Storage: close the lid tightly after use and store in a cool, dry place. A 270 g tub covers a lot of nail holes, so most of it will be stored rather than used, and a lid that is not properly seated leaves you with a skinned tub next time.

Hazard classification

This filler is not classified as hazardous under Safe Work Australia GHS 7. It carries no signal word and no hazard statements, and its composition is given as 100% ingredients determined to be non-hazardous or below reporting limits.

The safety sheet does add one note worth repeating: the product contains isothiazolinones — the preservatives that keep a water-based paste from spoiling in the tub — below the levels that require them to be listed, and repeated contact may cause sensitisation. Sensitisation is not irritation. It is the immune system learning to react to a material: once acquired it is generally permanent, and thereafter far smaller exposures will set it off. It builds up through repeated casual contact, not through one bad episode.

The comparison with the exterior version is the useful one. Selleys No More Cracks Exterior Wood Filler, which is the same kind of paste for the same kind of job outdoors, is classified — signal word Warning, Sensitisation — Skin Category 1, H317: may cause an allergic skin reaction. The interior product sits below that threshold. If you use both, the exterior tub is the one to put gloves on for.

For this one the precautions are the ordinary ones:

• Use a filling knife rather than a bare finger where you can, and wear gloves if you are filling for an extended session — that is what the sensitisation note above is about.
• Wear a dust mask when sanding. This filler can also be nailed and planed once dry, which produces its own shavings and dust.
• Wash it off skin with water before it dries, and wash your hands before eating, drinking or smoking.
• If any gets in an eye, wash it out immediately with water and seek medical advice if irritation persists.
• Keep it out of reach of children. Store the tub sealed in a cool, dry place out of direct sunlight.

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 No More Cracks Wood Filler Interior

How long does it take to dry?

At 25°C, 1–2 hours for a 1 mm application and 2–3 hours for a 2 mm application, depending on humidity.

What size does it come in?

A 270 g tub.

What colour is it?

A pine coloured paste.

Can I stain it?

Yes. It is stainable and paintable.

How do I get the stain to match?

Start light and darken progressively with further applications of stain. If you can, test on an inconspicuous area or an off-cut first.

Why does my stained repair look wrong?

Possibly because it is not finished. The final colour is not achieved until the varnish is applied, so judge the match after varnishing.

Can I nail or plane it?

Yes, both, once dry.

Do I need a second coat?

For a perfect finish, yes — a second thin coat, dried and then sanded lightly with very fine sandpaper.

Can I use it outside?

This is the interior product. Use No More Cracks Exterior Wood Filler for exterior timber.

What is the minimum temperature?

Do not use it below 5°C.

Can I fill the gap between my skirting and the wall with it?

No. Where movement occurs, use Selleys No More Gaps.

How do I clean up?

With water, before the filler dries.

How should I store the tub?

Close the lid tightly and keep it in a cool, dry place.