Warpping Problems caused by the wrong veneer core construction
Sure some of the workers made wrong core construction ,made the plywood warpping ….
Veneer Core is defined as plywood in which all the plies are made of veneer orientated with their plane parallel to the surface of the panel. In veneer plywood, the direction of the grain in adjacent plies is normally at right angles, with the outer and inner plies placed symmetrically on each side of a central ply or core. Standard plywood veneer is produced using a lathe, which peels a log in a similar manner to a blade pencil sharpener. Synthetic resin adhesive is applied to the veneer and they are assembled with the grain of each at 90° to the adjacent veneer.
VENEER CORE STRUCTURE DECIDE THE PLYWOOD WARPING OR NOT ?
As mos of the factories ‘s production managers have different kinds of VC structures ,even different quality levels of core veneer ,but the structure purpose is no warpping and must be flat …
Veneer Core is defined as plywood in which all the plies are made of veneer orientated with their plane parallel to the surface of the panel. Inveneer plywood, the direction of the grain in adjacent plies is normally at right angles, with the outer and inner plies placed symmetrically on each side of a central ply or core.
During the VC production,if any wrong veneer direction or location ,the finished plywood would be broken ,warpping or …the joints of the adjacents core veneer can not be the same direction and location …
ODD NUMBER OF PLIES OR EVEN NUMBER OF PLIES OF THE CHINESE PLYWOOD ?
odd number of plies or even number of plies of the chinese plywood ?
Visited one plywood factory ,found that they were using even number of plies for their chinese plywood ?18mm is just 10 plies ,normally 11 plies or 13 plies .But the quality is good without warpping and shrinking .
Also tried to find more factories like this factory,in the location closed to the factories ,most of them using even number of plies for theirplywood ?
Do you know where is the location ?
Plywood is made from thin layers of wood grain, glued together into a sheet of consistent thickness. The plies in plywood sheeting serve specific purposes and are arranged to maintain the integrity of the plywood by minimizing shrinkage and warping. Sheets are built from the bottom up, with each layer glued to the one below.
The front and back ply of each sheet of plywood are known as the back and the face. Both are aligned with the grain running with the length of the sheet. The front face is typically made from the best material, designed to be mounted face out, while the back will be of lesser material, designed to be hidden. The one exception to this rule is hardwood cabinet grade plywood, which has two smooth sanded faces, both suitable for finishing.
Plywood is always made with an odd number of plies, the minimum number being three. The thicker and better the quality of the plywood, the more plies it will have. The odd number plies, including both outside plies, are always aligned with the grain running vertical or length-wise with the panel. This is consistent throughout the thickness of the sheet, no matter the grade of plywood.
Even numbered plies are aligned perpendicular to the face and back plies with their grain running the width of the panel, or horizontal. This cross-grain positioning helps to prevent permanent warping and minimizes the effects of swelling and contraction that occur due to changes of temperature and humidity. As with the odd numbered plies, this is consistent throughout all standard plywood and adds greatly to its structural integrity.
FACTORIES’S CAREFUL MAKE-UP HID THE SIGNS OF EDGES CORE VOIDS AND OVERALPS OF THE PLYWOOD
- Factories’s careful make-up hid the signs of edges core voids and overalps of the plywood.This is only a palliative.
PLYWOOD CORE CONSTRUCTION LAY UP: 1-STEP OR 2-STEP OR 3-STEP MANUFACTURING PROCESS?
How many steps of the core construction lay-up will gives an exceptionally smooth uniform surface virtually eliminating grain transfer,more commonly found in a one step process.
Have you checked with your chinese suppliers,how many steps they produce for your plywood ?
HOW OUR WOOD VENEER PANELS ARE CONSTRUCTED
Source from http://www.panelspec.com/
Our wood veneer panels are some of our most popular products. Why are they in such high demand, and what makes them such a great investment? That has to do with our high-quality production processes, our top-notch materials and the unique functionality and design flexibility they offer.
Are you considering wood veneer panels for your building? Let’s take a deeper look at these products and how they are made.
- Four-part building process – Each of our wood veneer panels is made up of four parts. On the very bottom is the backer, which balances the panel and prevents it from warping or shrinking as humidity levels change. On top of that is the core, a particle board that adds rigidity and fire ratings, and helps to hold the panel up. On the very surface – the visible part – is the wood veneer. Around the edges of the entire panel, there is a finished wood banding, which covers the raw edges around the perimeter to hide the inside layers and deliver a polished look.
- Numerous pattern options – Our wood panels come in 18 different patterns, including flat cut walnut, quartered cherry, Australian lacewood, curly maple and many more. You choose whichever matches your design and aesthetic best.
- Leaves are book-matched and balanced – In order to ensure a balanced panel, each leaf on the panel is the exact same width, then leaves are placed in a book-matched pattern. The panels are then typically applied in a random pattern on the wall.
All of our wood panels are durable, meet AA architectural grade designations, and have environmentally friendly UV coatings in either a glossy or a satin sheen. You can also opt for clear or custom-stained panels.