![]() Springs or webbing are attached to the frame to give the seat a desired amount of elasticity. An old rule of thumb suggests that rails of 3″ or more in width should be 1-1/8th” thick, while rails less than 3″ wide should exceed 1-1/8″ thickness. If we assume that a certain 1″x 1″ beam will sustain a load of 100 pounds, then a beam 1″ thick and 2″ wide will sustain 200 pounds. The engineering principal involved is that strength varies directly with rail width and with the cube of thickness. Since lumber costs increase rapidly with increasing board thickness, some manufacturers may hold down frame coasts by skimping at the precise point where ample strength is most important. Major joints need the additional support of corner blocks, which should be glued and screwed into place. ![]() The gang nail is a metal plate with saw teeth, which immobilizes the joint when it is pressed into the wood with a hydraulic press. Epoxy coated staples and gang nails are also commonly used. Wooden frame joints are often double doweled, which means that round wooden pegs are fitted into holes in two adjacent frame sections and glued. They are sometimes used at critical stress areas when maximum strength is needed. Kiln drying reduces the moisture content of the lumber, a process which inhibits checking, splitting, and strengthens the finished product.Įngineered wood products may look not strong, but can be stronger than hardwood because the layers add to the strength. White oak, red oak, and American elm are good, and hard maple and birch are acceptable. ![]() White ash is a superior frame making wood. Hardwood frames are usually constructed from kiln dried mixed hardwoods. Quality frames are generally made of solid wood, but plywood, engineered wood products, a variety of polymers and metals are also used. If a frame is unstable, an upholstered piece will not be durable, no matter how fine or costly its design, padding, cushioning, or cover. The frame gives structural support and determines the basic shape of any piece of upholstered furniture. A basic upholstered piece is composed of a frame, springs, foam, decking, cushioning, padding, and a cover. The overall quality of the materials and construction techniques used dictate the comfort level of an upholstered piece and its ability to satisfy the consumer over the long term. The consumer usually never sees the construction features of an upholstered piece, but they are important.
0 Comments
Leave a Reply. |