" " wisno wood furniture finishing: Plywood for furniture

Friday, September 24, 2010

Plywood for furniture

Plywood is thin sheets of wood veneers that are laminated together to make a thick wood panel. The plywood is than used to make panel in the woodworking industry. Plywood can be manufactured in various thicknesses with the variation on the number and thickness of the layer is used, the standard size is 1/8 in. to 1/4 in. with the 4 ft wide and 8 ft long. The outer sheet of plywood is usually made from veneers with better quality. There are two outer of the plywood the front and the back. The front is also called the plywood face can be layered with the best veneer, while the back can use the same veneer but with lower quality. The quality of the face sheet and back of plywood are described at the specifications of this plywood as the quality of the plywood.  For example an A grade teak plywood both side means that the plywood use teak veneer with A grade quality at the face and back.  
Rear sheets of plywood veneer can be made from the same or different depending on the quality wise. Although the back of the plywood can be made with a veneer with different types but the veneer the back must be carefully selected. The back veneer should in balance with the veneer at the front to prevent the bowing caused by the differences of the wood movement due to the changes of the temperature and air humidity. The back veneer must use materials that are relatively balanced with the front in terms of movement resulted by the changes in heat and water absorption. 
A thin layer of wood (veneer) is obtained from a log which slashed with variety way of slicing or peeling by rotating it against knife. The wood slicing is slow, expensive but gives highly figured grain pattern and matched for furniture and cabinets and specialty panels. The rotary slicing is the less expensive; the all grade panel plywood mostly are use the rotary cut veneer. To see more about the veneer slicing, you can view our previous article: wood veneer for furniture.
Veneer sheets from the log slicing then are cut to fit the width of the desired size and separated according with the quality. Sap wood parts are separated by heartwood and are collected in accordance with the grade. Then the veneer is taken to the kiln dry or even where it is dried. Out of the drier the veneer usually has moisture content ranging between 5%-7%. The dry veneer is then graded and stored to be used and be jointed in plywood manufacturer.
At this time the plywood is also used to call the construction panel that uses sheet of wood (veneer) at the front and the back with a core in the middle. A particle board, hardboard, M.D.F. or laminated wood that is overlaid with wood veneer at the outside layer sometimes is also  called as plywood. The veneer sheets that are going to be used as the face can be prearrange to make some special pattern. The wood veneer pieces are cut and then be jointed to form the desired patterns using tape or glue edge. After the veneer spliced and attached in accordance with the desired pattern, then a glue need to be evenly coated on its surface. While a sheet core to make the panel is also need to be prepared with the same glue coated. Veneer sheet is then attached to the panel and pressed until the glue dry to produce a panel with a wood veneer on its surface. The pressure used usually ranges between 150 -300 psi. The hot metal plat can be  heated to heat the glue at the time of pressing. This method is known as a hot press which can make the gluing process can be done very quickly. With the 250 F temperature and special glue the drying process can take time about 2-5 minutes.  



The advantages of plywood
 
Plywood change the timber that has varies properties becomes more uniform, strong and versatile. Wood has a higher strength along the direction of grain compared with the across the grain direction, a laminated veneer with the opposite direction will produce a stronger panel. Cross lamination play in the plywood panel will reduce the risk of splitting and puncture to produce panel with more rigid and impact resistant. Plywood can produce panels with the strength more than 2 times of a solid wood panels from the same log with the same thickness. Wood dimensional changes resulting from changes of the wood moisture content with radial direction (across the grain) can be much larger than the tangential direction (along grain). A cross laminated plywood can neutralize this problem to produce a panel that is more flat and stable. 
As intermediate products, plywood wood has an advantage because having the wood looked. The panels of MDF, particle board or barecore may need a wood veneer at the face to produce the wood looked. But the plywood is already has the wood veneer at its surfaces. The quality of the wood veneer is already specified at the specification. It can be cut and shaped to make the woodworking product and be finished as the wood panel.
Simak
Baca secara fonetik

4 comments:

  1. Nice & interesting articles, I really like reading on this blog, your idea is more helpful for me and to the other as well.
    Jody

    ReplyDelete
  2. Good article. Your series of education on wood types are useful for newbie as well as experienced woodworkers. For sanding tools to help with your project, check out our Best Drum Sanders. Cheers!

    ReplyDelete
  3. Picking plywood for furniture that is made with high quality should also be more cost effective and long-lasting because quality of plywood is very high.
    1 inch plywood

    ReplyDelete