Natural Birch Plywood (Fresh and Bleached ) grading checklist and knowledge

For Chinese Natural Birch Plywood :,normally have two types of face veneer,one is natural birch face veneer from the fresh birch logs .Another is the bleached natural birch face veneer ,white color bleached natural brich plywood .When buying the natural birch plywood,make sure you want white natural birch plywood ,or natural birch plywood ,the wood grain is even the same ,but color have much difference .The natural birch face veneer normally have black mineral streaks in big are of the whole face veneer ,but not much knot holes or knots .That is the big difference from the white birch face veneer .

The white color natural birch looks like be easy telegraphing ,the red color natural birch hide the telegraphing .

If bleach the natural birch face veneer to white color ,the wood grain would be very nice and good looking like white maple or cherry .That is why some manufacturers using bleached natural birch to make good wood grain furniture or cabinet grade kitchen .

They have plain sliced face veneer and rotary cut whole piece face veneer ,so when you place the Order,check exactly.

The word natural brings to mind certain connotations like “beauty”, “warmth” and “purity”. Merriam-Webster defines natural as “occurring in conformity with the ordinary course of nature (the genetically controlled qualities of an
organism): not marvelous or supernatural”.Wood is a product of nature, and in some cases, will accentuate and enhance a project design when used in its purest, or natural, state. However, as a product of nature, each wood species has certain intrinsic and industry-acceptable characteristics, which can vary from tree to tree and flitch (half log) to flitch. It is precisely these naturally occurring variations
that provide such richness and uniqueness to each project design. Certain wood species such as natural maple, birch and ash can vary widely
in color range, which is why in many cases select white is specified so that the sapwood can be accumulated and spliced together to create a consistent color. The photos and information in this brochure are designed to assist you  in specifying and receiving the product you envision.

Birch veneer is classified by coloration into three basic groups: natural, select white and select dark. Natural birch contains unlimited amounts of heartwood and sapwood. Select white birch contains only light-colored sapwood.Select dark birch contains only red or brown heartwood.

Rotary cut natural birch veneer displays fine wood texture and a very irregular grain pattern.
The grain pattern is accentuated by the presence of light-colored sapwood invaded by much darker heartwood. The extreme coloration differences may be highlighted or subdued when the  face veneer is stained and topcoat finished. These extreme coloration differences should be considered before specifying natural birch

Some natural birch is full red color ,also call it red birch from some suppliers .Some natural birch has big color variation .

If make UV prefinished natural birch ,the face veneer should be a little thicker than raw birch plywood face veneer to make sure no telegraphing and should be selected natural birch face veneer without major manufacturing defects such as open splits and shrinkage and rough cutting area and knife marks …
B-2 Grade 1/4″ x 4′ x 8′
B-2 Grade 3/4″ x 4′ x 8′
D-3 Grade 3/4″ x 4′ x 8′
E-2 Grade 3/4″ x 4′ x 8′
It is used in cabinet building, fixtures, furniture, and general construction.

“Each customer is different, has different requirements and needs, but all aim to the same: comfort, beauty, safety and uniqueness”.

Some of the natural and manufacutring defects are below :

Cut
Grade Description
Color and Match
Sapwood
Heartwood
Color Streaks
Color Variation
Sharp Joint Contrast
Matching
Book
Slip
Veneer Piece Width
Plain Sliced
Natural Characteristics
Burls/Pin Knots #
Burl Size
Pin Knots #

Repaired Knots
Mineral Streaks
Bark Pockets
Worm Tracks
Vine Marks
Cross Bars
Manufacturing Characteristics
Rough Cut
Hairline Splits
Blended Repairs

How to Bleach Plywood

If you want to lighten the color of plywood, there’s a bleach for the job, and if you want to remove stains, there’s a bleach for that, too. In fact, you can choose from two different bleaches for removing stains. Bleaching plywood isn’t much different from bleaching solid wood, with one important difference. Plywood is laminated in layers, and the surface layer on which the bleach is acting is usually very thin. The bleach doesn’t have to penetrate as deeply to do its job and consequently may not need as much time to work.

Strip off any existing finish with a chemical stripper. Sand the plywood with 80- or 100-grit sandpaper to remove finish residue and open the grain. Sanding to open the grain is a good idea even if the plywood is unfinished.

2

Choose the bleach you plan to use based on the task you wish to perform. Oxalic acid is the best bleach for removing iron or water stains, which usually appear as grayish blotches. Chlorine bleach, on the other hand, is the best bleach for removing dyes and stains from tea, fruit juice and wine. Finally, to lighten the wood, use peroxide bleach, which usually comes in a two-part system that you mix just before using it.

3

Use oxalic acid by mixing the crystals with water to form a saturated solution, or one in which no more crystals will dissolve. Use a paintbrush to spread the solution over the whole surface — not just the stained section — then let it dry. You may need several applications to remove the stain.

4

Bleach out unwanted colors and dyes with a saturated solution of sodium hypochlorite, available from a swimming pool supplier, and water. Mix only enough for one application. Apply the bleach to the wood with a brush and wait until it dries. If the color isn’t completely gone, mix a second batch and apply it. If two applications don’t remove the color, you’ll probably have to sand out what’s left of the stain.

5

Mix a two-part, or “A/B,” wood bleach immediately before using it. Add part “A,” which is usually sodium hydroxide, to part “B,” which is hydrogen peroxide. Paint the mixture onto the plywood and allow it to dry. One application is usually sufficient to produce an immediate effect.

6

Neutralize the wood after you’re finished bleaching it. Wash the surface with a solution of one part white vinegar to two parts water to neutralize an “A/B” bleach. Mix a solution of 2 heaping tablespoons of baking soda per quart of water to neutralize oxalic acid. Wash the surface thoroughly with distilled water after using chlorine bleach.

Things You Will Need

  • Chemical stripper
  • 80- or 100-grit sandpaper
  • Oxalic acid crystals
  • Paintbrush
  • Sodium hypochlorite
  • Two-part, or “A/B” wood bleach
  • White vinegar
  • Baking soda
  • Distilled water

Tip

  • Bleaching isn’t just for correcting color defects. You can use it creatively for interesting effects and to color-match two dissimilar pieces of plywood. Bleaching raises the grain of the wood. Knock the grain back down by sanding the plywood after the bleaching is complete.

Warning

  • You may have to treat some problem stains with more than one bleach. If so, neutralize the first bleach before applying the second. Combining bleaches can create dangerous fumes. Wood bleaches are caustic and their fumes are harmful, so wear rubber gloves, protective eyewear and a respirator when working with them.

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