2019-12-28

Blue Stains on Oak Veneered Panel

For BLUE STAINS, it occurs more frequently on red oak than on white oak, and it occurs more frequently in summer than in winter (northern hemisphere).


Today, let's discuss the main reasons for the formation of BLUE STAINS and see how to avoid it.


Reason One

In the process of planing and cutting oak log into oak veneer, if workers do not clean the dust or garbage on their hands or there are some sweat on their hands, or if there are some moisture, dust or garbage on the blade of the planing and cutting machine(which is highly speeding and with high temperature), the chemical components in the log will have an oxidation reaction with the blade to produce a blue or dark stain on the wood, which is called BLUE STAINS.


Reason Two

If the moisture of the log is too large, the cyanobacteria will grow and multiply, resulting in blueness on the finished veneer.


So, the most important thing is to operate cautiously and pay more attention in the production process of oak veneer & finished oak plywood to avoid the occurrence of BLUE STAINS. We can avoid BLUE STAINS from below aspects -


1. In the process of planing and cutting oak log into oak veneer, workers make sure to wear work gloves and keep them clean and do not touch wood directly with sweaty hands.


2. In the process of planing and cutting oak log into oak veneer, the blade of the planing and cutting machine should be kept clean without dust or garbage or moisture.


3. Try to choose and use the high-grade imported blades of planers with low iron content, which are not easy to oxidize with wood under high temperature and fast operation.


4. To well control moisture content of oak log and storage environment of oak veneer.


5. After BLUE STAINS is generated on oak veneer, we can solve it by pickling.


6. If BLUE STAINS is very tiny, after lamination on wood-based panels, we can remove it with the professional utility knife and repair material.


7. If BLUE STAINS occurs some time on the finished laminated wood-based panels, when inspecting and sorting cargo, we will take it out.


That is why our wood-based panels need to be stored in our warehouse several days after the finished production and we call these days “maintenance of wood-based panels”. And, that is also why our inspection and sorting of wood-based panels is always after “maintenance of wood-based panels” and just before loading.


After several days’ maintenance, the finished wood-based panels’ condition will be relatively stable. If there is none of BLUE STAINS after our cargo inspection, after you receives the goods, the possibility of the occur of BLUE STAINS will be very small.



Don’t worry for the quality of Oak Veneered Panel. We have professional inspectors and high quality inspection standards for it as below -


About Oak Veneer:

1. American oak veneer,
2. Thickness of veneer: 0.2mm/0.3mm/0.5mm, etc. depending on your needs
3. 3A grade
4. No color difference / pattern burst / seam / black difference, etc.,
5. Black dots are not allowed to exceed one row , and its quantity does not exceed 4, and the size is not larger than the size of a mung bean.

6. Clean blue stains.


About Workmanship of Oak Veneered Wood-based Panel:

No knife cutting, no digging, no discolorations, no glue penetration, no obvious seams/overlaps.


We ACEALL WOOD always adhere to the original intention of "well checking each sheet of basic life panels for you", and use excellent products and services to build a better life for families around the world, conveying our understanding of a better life and concern for the living environment.

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