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Sambo1111
27th June 2018, 10:03 AM
With the rise in popularity over the years of Eucalypt timber (Blackbutt, Wormy Chestnut, Stringybark, Messmate) for use in furniture and bench tops here in Australia, i have run in to a problem in finishing/polishing. A characteristic that many people like in these timbers is the occurance of natural defects such as gum veins, borer holes and surface checks.

A job I did a few years ago was a kitchen with benchtops made from Blackbutt with a clear 30% satin two pack lacquer applied. Tops looked fantastic once installed, fast forward a month or so and i received a call back due to the finish. Upon inspection, around all of the small surface checks (small hairline cracks) the lacquer was lifting/peeling. I asked the client what they were doing to clean the tops and they said all they were doing was wiping over with a damp cloth and then drying straight away with a towel as i instructed them.

To solve the problem i stripped the lacquer finish off, sanded back to the raw timber surface and applied three coats of kitchen bench top oil (Feast Watson i think it was). On top of this i applied a coat of carnauba wax. This came up a treat and i have had no such issues since. I advised the client to clean and apply more wax if the finish ever starts to dull off which hasn't been required.

The conclusion i arrived at was that the moisture from wiping with the damp cloth was getting underneath the finish through the small surface checks and causing the finish to lift/peel. Hence why we haven't had the problem with the oil/wax finish as this tends to penetrate the timber surface rather than sit on top. This experience has left me very cautious to apply a film finish like lacquer to these timbers ever again. Clients are still regularly wanting to use these timbers in their projects and i have been recommending the oil/wax finish.

I am by no means an expert on timber finishing, has anyone run into this problem before? Could there be any other explanation?

I have attached some pics of the lacquer lifting/peeling and some of the surface checking which is present in these timbers.


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FenceFurniture
27th June 2018, 10:51 AM
Blackbutt is a very splitty timber - maybe those tiny cracks developed after the bench went into place? The Carnauba wax would probably have filled the cracks up again, so that moisture couldn't get into the crack.

The first three pics look very much like reclaimed timber, and I find it almost always has cracks in it - just the way it is.

qwertyu
27th June 2018, 02:50 PM
Ingrain design in Melbourne exclusively use osmo poly x for their wet area cabinets like bathroom vanities.

edit: might be worth asking them what maintenance is required

Sambo1111
27th June 2018, 07:24 PM
Blackbutt is a very splitty timber - maybe those tiny cracks developed after the bench went into place? The Carnauba wax would probably have filled the cracks up again, so that moisture couldn't get into the crack.

The first three pics look very much like reclaimed timber, and I find it almost always has cracks in it - just the way it is.

From memory the surface checking was there before. Yep that is the look a lot of people are trying to achieve. Surely other people have had a similar problem?

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Sambo1111
27th June 2018, 07:26 PM
I did read up about this, looks good. Sounds like a perfect product for these timbers.
Ingrain design in Melbourne exclusively use osmo poly x for their wet area cabinets like bathroom vanities.

edit: might be worth asking them what maintenance is required

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