2-pack wood filler suitable for all wood types

from 2 reviews
Cosmobois packaging
  • Wood putty available in light oak suitable for all wood types
  • Quick drying and will not shrink or crack
  • Once cured can be machine sanded, screwed, sawn, filed etc.
  • Compatible with all finishes, both single and 2-pack
  • Can be tinted with universal colorants

Cosmobois is a 2-pack wood filler that can be applied to all types of wood. Quick-drying and highly flexible Cosmobois will not shrink or crack and when fully cured can be cut, screwed, and drilled. Cosmobois is easy to sand, both manually and mechanically and is compatible with any single or two-pack finish.

It can also be tinted with universal colorants up to 2% before mixing in the hardener for a specific colored finish.

Ideal uses for Cosmobois wood filler

  • Filling dents and scratches in wooden door panels
  • Repairing damage to wooden gates
  • Restoring vintage furniture
  • Completing joinery work to a higher standard
  • Repairing damage to decking in the yard

Surface Preparation

Surfaces must first be clean, dry and free of dirt, grease, grime, all loose material and other contamination. Remove all loose and old finishes from around the area to be repaired.

Thoroughly abrade the surface using a coarse abrasive paper. Wipe the surface clean with acetone, ethyl acetate, methylated spirits (de-natured alcohol) or similar to remove any abrasion residue.

Do not use White Spirit.

Applying Cosmobois wood filler

Tinting (optional)

Add 2 % (max) of universal colorant to the filler and mix in well before mixing with the hardener.


Add 2% of the hardener to the quantity of filler for 10 minutes drying. As a guide 1 coffee bean size of hardener to 1 chestnut size of filler. In cold weather increase the amount of hardener. In hot weather decrease amount of hardener.

Ensure the hardener and filler are well mixed. Increasing or decreasing the amount of hardener does not affect the overall curing time.

Applying Cosmobois wood filler

Work the filler into the crack or hole and smooth off with a filling knife. For repairs deeper than 25 mm – build up in layers allowing it to dry between applications. For a smooth finish sand (100 grit paper) before applying your finish. Allow 24 hrs after application before machining (drilling, mechanically sanding, tapping etc.).

Clean Up

Clean tools immediately after use with acetone, ethyl acetate or similar. Dispose of any unused hardener/filler mixture in accordance with local regulations. Do not put it back in the container.

Things to Remember

  • For narrow cracks rake out to enlarge
  • Stir filler well before mixing with hardener
  • Do not mix filler and hardener in the can
  • Apply between 10°C and 25°C

2 reviews for Cosmobois

  1. Branch Fields Verified Owner

    Initial review, and plan to update after more time. Used for two different projects: 1) repair the corners of my window stools (the inside of a window sill) including a large tear out chewed up by the new beagle; project resulted in happy wife. 2) fill in knot holes, drill holes, and checking on a new picnic table. It sands and tools very well after curing. For outdoor use, I strongly recommend using in the shade, and keeping the work in the shade until fully cured, not just dried. Drying time inside is a couple of hours. Drying time outside on a hot day, about 5 minutes. Stated cure time is 24 hours. I had to redo part of the picnic table as it doesn’t fully adhere until cured – the expansion of the wood In the hot sun cause the cracks to reopen. Routed out the cracks, reapplied, and allowed to fully cure in my garage. No more issues so far, even out in the hot sun. Only two complaints 1) the packaging: The hardener had separated a bit, and the plastic piece supplied as an mixer/applicator tool was a bit brittle. 2) I wish there was advice on better application, as it is very sticky on skin, plastic wrap, nitrile, and latex. Next time, will try using a silicon applicator and see if it applies better with that. Not a big deal.

  2. Marty Verified Owner

    I haven’t applied the product at this point. I have 5 antique teak deck and steamer chairs (no screws but brass hardware). There are a few cracks due to lack of oil that require a floated filler. Will update when I get to that stage.

    • Sophie Mamann

      Looking forward for your feedback Marty. Do not hesitate to send us some before/ after photos 🙂

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This coverage indication is only a guide and actual coverage is dependent on surface type, age, porosity etc.
Tools: Filling knife
Suitable for: Interior and exterior use
Clean up: Acetone, ethyl acetate or similar
Drying Time: 10 minutes at 20°C
Curing Time: Allow 24 hours before machining
Suitable Surfaces: All wood types