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Core Specie Attributes – Domestic Fir & Poplar

Core Specie Attributes - Domestic Fir & Poplar

The core is made with alternating veneer inner plies. The inner-ply species are usually fir for production out of west coast mills and poplar for production out of east coast mills. Veneer core panels are relatively light in comparison with composite panels, typically weighing about 70lbs per 3/4″ panel. Veneer core offers great strength and stability with better spanning properties than either PBC or MDF. Veneer core does have a wider variance in thickness in comparison with highly engineered PBC or MDF.
As hardwood veneer skins become increasingly thinner, the quality of the inner plies under the veneer face and back become increasingly important to the quality of the panel. Due to this, veneer is not as forgiving and varying degrees of core transfer is possible depending on the surface veneer or core construction specified. The platform and core species is determined by the types of trees that grow in the region of manufacture. Which is better: fir or poplar cores? It really comes down to overall individual preference and past application experiences. The larger domestic plywood manufacturers have plants on both the west and east coasts; therefore, core species is not a preference by manufacturer and is truly dictated by geographic specie availability.

Some hardwood plywood experts put the two top core species to the test. The results are in the chart below:

Attributes Fir Core Hardwood Plywood Poplar Core Hardwood Plywood
Bending strength High Moderate
Density Moderate Moderate
Movement after drying Low Moderate
Sanding Good Difficult
Screw holding Good Good
Screwing Good Good
Shaping Good Difficult
Toughness Moderate Low
Weight Moderate Moderate