The moisture content of log veneer is crucial for effective wood drying and bonding. It’s typically measured as absolute moisture content and must be within a specific range to ensure good drying efficiency, plywood bonding, and overall quality of the final product.
How Moisture Content Affects Plywood Bonding Quality

-High Moisture Content: Excess moisture weakens bonding strength and can lead to defects like delamination, warping, or surface cracks.  

-Low Moisture Content:Too little moisture also reduces bonding strength, as the adhesive may not bond properly.  

-Optimal Moisture:The ideal moisture level depends on the wood type, adhesive, and plywood performance needs. Proper moisture control ensures strong, durable bonds.

Moisture Content for Different Types of Adhesives

3.Moisture Content for Different Wood Species

4. Combined Effects of Moisture Content on Bonding Strength and Defects

Bonding Strength:
Studies show that a moisture content of 5%-15% provides good bonding strength, with 7%-8% being ideal.
If less glue is applied, slightly higher moisture content can help maintain bonding strength.
Plywood Defects:
A moisture content between 5%-8% minimizes issues like deformation and surface cracking.
5. Final Recommendations
Based on the type of adhesive and wood species, here are the optimal moisture content ranges:

Choosing the right moisture content helps balance bonding strength, minimize deformation, and reduce surface defects, improving the overall quality of the plywood.