M.R. Grade Plywood:
Manufactured as per IS: 303 specification premium quality M.R. Grade plywood caters to every need of customer. Its excellent quality perfectly matches the economical frame. With a normal and minimal climatic alteration, plywood is best recommended to grace all interior applications, that includes office and computer roof furniture, your dwelling place and business establishments.

PLYWOOD

Plywood is one of the most commonly used wood products available today. It shows up everywhere. It is extremely versatile, strong, durable, and comes in several grades and thicknesses, dependent on quality and thickness - all standard sheets of plywood are 4 feet by 8 feet. The sheets are from 1/4 to 3/4 inch thick - though some special sheets may be thicker.

Plywood consists of layers of veneer laid crossways to each other, glued and pressed together to form a sheet. Standard indoor plywood is not made with a really good waterproof glue so after a few dousing of water the board can start to separate. You need to treat the wood with sealer, varnish, or paint to waterproof and protect it. Exterior plywood is made using waterproof glues and, often, with treated lumber - that is, wood that has been waterproofed by soaking in chemicals. You can usually tell if the wood is treated because it has a greenish hue. Marine ply is the most expensive and is made with high quality materials and glues that resist moisture. This, as the name suggests, is most often used in boat construction.

Plywood is constructed by gluing together a number of layers (plies) of wood with the grain direction turned at right angles in each successive layer. This design feature makes plywood highly resistant to splitting. An odd number (3, 5, 7) of plies is used so that they will be balanced on either side of a center core and so that the grain of the outside layers runs in the same direction. The outer plies are called faces or face and back. The next layers under these are called crossbands, and the other inside layer or layers are called the core. A plywood panel made of three layers would consist of two faces and a core.

There are two basic types of plywood: exterior and interior. Exterior plywood is bonded with waterproof glues. It can be used for siding, concrete forms, and other constructions where it will be exposed to the weather or excessive moisture. Interior plywood is bonded with glues that are not waterproof. It is used for cabinets and other inside construction where the moisture content of the panels will not exceed 20 percent.

Plywood is made in thicknesses of 1/8 inch to more than 1 inch, with the common sizes being 1/4, 3/8, 1/2, 5/8, and 3/4 inch. A standard panel size is 4-feet wide by 8-feet long. Smaller size panels are available in the hardwoods.
Plywood can be worked quickly and easily with common carpentry tools. It holds nails well and normally does not split when nails are driven close to the edges. Finishing plywood presents no unusual problems; it can be sanded or texture coated with a permanent finish or left to weather naturally.

There is probably no other building material as versatile as plywood. It is used for concrete forms, wall and roof sheathing, flooring, box beams, soffits, stressed-skin panels, paneling, shelving, doors, furniture, cabinets, crates, signs, and many other items. Softwood Plywood Grades

All plywood panels are quality graded based on products standards (currently PS 1/74). The grade of each type of plywood is determined by the kind of veneer (N, A, B, C, or D) used for the face and back of the panel and by the type of glue used in construction.

Many species of softwood are used in making plywood.

Making Plywood

Plywood is made from an odd number of constructional veneers bonded face to face with the grain running in alternate directions (cross bonding) it then goes in between the shelves of a large hydraulic press, these shelves are heated and squeezed together tightly putting great pressure on the plies, the heat dries the glue and sticks the plies together. Then the plywood is trimmed and can be sanded to give a smoother finish.

The reason for using an odd number of veneers is that the sheet of plywood must be balanced as near as possible to be stable. Plywood can still twist even when it is balanced because no two veneers are completely identical and the tensions are never perfectly balanced. Another factor that can cause warping is the wetting or heating of one face of the ply; this will cause the veneer to expand or contract, both of which can pull the board out of true.

TWO PIECES WARP BUT THREE PIECES OR MORE WILL NOT WARP.

It shrinks, warps, twists and swells less than ordinary wood and has great resistance to splitting at the ends, this permits carpenters to fasten plywood sheets with nails or screws close to the edges. The outside veneer is called face and back and the centre ply or veneer is called core. The quality of the plywood is defined according to its face and back veneer grade. The simplest plywood is made of three layers of veneer, with the grain direction of the two outer sheets being parallel. The greater the number of veneers the stronger the plywood.

Plywood's main advantage is that by gluing together an odd number of layers of veneer, a material that is lightweight and workable, yet rigid and strong can be obtained. Plywood can also be cut to exact sizes worked into curved shapes and produced in large panels with a smooth surface. Expensive woods can be used for the face because only thin sheets are needed, plastic or metal faces are sometimes used to provide surfaces that resist starching.

 

PLYWOOD CAN BEND

Uses of plywood

Plywood is used chiefly for floors, to line roofs and walls, and for wall paneling. It is particularly suited for the forms used for shaping concrete for homes, buildings, bridges and dam foundation. Carpenters and cabinetmakers find wide use for plywood in furniture, cabinets and counters. Manufactures use it in boats, lorry trailers, office equipment, packing cases, trains, cars, road signs, sporting goods and other products.