Thread: left field question

Yes. Many of the Ausy hardwoods sink as their density is greater than water.

Waiting for Runge to weigh in on this one, but yes there are several.

I suppose you'd have to look for a timber which has a specific gravity than 1.0. Specific gravity refers to something that will float or sink in water. Therefore where water equals 1.0, something which floats is less than 1 and something which sinks is greater than one.

For example:

Lignum Vitae, 1.280 - 1.370, therefore it will sink.
Mild steel, 7.85, therefore it will DEFINITELY sink.

This may help you also.

For many timbers it depends on whether they are green, air dry or bone dry since this affects the density.

The density of fresh water is nominally 1000 kg/m^3 at room temperature so when the density of wood is less than this the wood will float.

From the forests products commission site.

EG Mulga
Green density is about 1330 kg/m3, air-dry density about 1200 kg/m3, and basic density about 1025 kg/m3.
so this will always will sink

Spottie
Green density is about 1150 kg/m3, the air-dry density about 970 kg/m3, and basic density about 790 kg/m3.
So when it is air dry or drier it will just float

Radiata
Green density is about 1000 kg/m3, and air-dry density about 590 kg/m3 in 30-40 year old and about 480 kg/m3 in 10-20 year old trees. Basic density is about 490 kg/m3 in 30-40 year old and about 405 kg/m3 in 10-20 year old trees.

Sandalwood
Green density is about 960 kg/m3, air-dry density about 900 kg/m3, and basic density about 785 kg/m3.
It will always float

So sometimes even green radiata will just sink.

These are all average figures. The density of the timber (and hardness) will be greater (or lesser) than this depending on where it is from on the tree and the age of the tree. Compression wood under branches and on buttresses can be 10-15% denser,

For more species look here.