The corrugated fastener mars the appearance of the surface into which it is driven, so use it only on the backs of picture frames and the like. A more satisfactory type of fastener for a joint between end mitered members is the biscuit. This is a thin piece of wood or veneer that is glued into a kerf cut in the thickest dimension of the joint. Use the biscuit in the following manner:. A joint between edge mitered members can also be reinforced with a spline.
This is a thick piece of wood that extends across the joint into grooves cut in the abutting surfaces. A spline for a plain miter joint is shown in Figure Cut the groove for a spline either by hand or with a circular saw. A three-sided recess running with the grain is called a groove, and a recess running across the grain is called a dado.
A groove or dado that does not extend all the way across the wood is called a stopped groove or stopped dado. A stopped dado, also known as a gain, is shown in Figure A two-sided recess running along an edge, as shown in Figure 27 , is called a rabbet T. Dadoes, gains, and rabbets are not, strictly speaking, grooves; but joints that include them are generally called grooved joints.
The procedure for grooving or dadoing with the dado head is about the same, except that in many cases you can build up the dado head to take out all the waste in a single cut. Cut a stopped groove or stopped dado on the circular saw, using either a saw blade or a dado head, as follows:. A rabbet joint requires two cuts; the cut into the face of the wood is called the shoulder cut, and the cut into the edge or end is called the cheek cut.
A rabbet can be cut on the circular saw. Make the shoulder cut first, as follows:. On some jointers, a rabbeting ledgeattached to the outer edge of the infeed table can be depressed for rabbeting, as shown in Figure The ledge is located on the outer end of the cutterhead.
To rabbet on a jointer of this type, depress the infeed table and the rabbeting ledge the depth of the rabbet below the outfeed table, and set the fence the width of the rabbet away from the outer end of the cutterhead.
When the piece is fed through, the unrabbeted part feeds onto the rabbeting ledge. The rabbeted portion feeds onto the outfeed table. Various combinations of the grooved joints are used in woodworking. The tongue and groove joint is a combination of the groove and the rabbet, with the tongued member rabbeted on both faces. In some types of paneling, the tongue is made by rabbeting only one face. A tongue of this kind is called a barefaced tongue.
A joint often used in making boxes, drawers, and cabinets is the dado and rabbet joint, shown in Figure As you can see, one of the members is rabbeted on one face to form a barefaced tongue. The mortise and tenon joint is most frequently used in furniture and cabinet work. In the blind mortise and tenon joint, the tenon does not penetrate all the way through the mortised member. This type of joint is shown in Figure A joint in which the tenon does penetrate all the way through is a through mortise and tenon joint, shown in Figure Besides the ordinary stub joint seen in Figure 31 view A, there are haunched joints, as seen in view B, and table haunched joints, as seen in view C.
Haunching and table haunching increase the strength and rigidity of the joint. The layout procedure for an ordinary stub mortise and tenon joint is shown in Figure The shoulder and cheek cuts of the tenon are shown in Figures 33 and Please note that the saw guard does not appear in these figures to better show the relationship of the blade to the stock. To maintain the stock upright while making the cheek cuts, use a push board similar to the one shown in Figure Tenons can also be cut with a dado head by the same method previously described for cutting end half lap joints.
Mortises are cut mechanically on a hollow chisel mortising machine like the one shown in Figure The cutting mechanism on this machine consists of a boring bit encased in a square, hollow, steel chisel. As the mechanism is pressed into the wood, the bit takes out most of the waste while the chisel pares the sides of the mortise square. A permanent joint does not allow dismantling of joined parts without breaking them.
As the name suggests, these joints are permanent in nature and usually offer a sound and leak-proof joining. Welding is the fast and foremost example for this category. Apart from welding, rivet joint, soldering, brazing, many adhesive bonding, etc.
A temporary joint allows disassembly of assembled structures without rupturing the components. Easy disassembly makes inspection and maintenance very easy. However, strength of the temporary joints may not be as high as in a permanent joint. Various differences between temporary joints and permanent joints are given below in table form. Skip to content. Differences between temporary joint and permanent joint Temporary Joint Permanent Joint Temporary joints allow easy dismantling of assembled components without breaking them.
Temporary joints are not necessarily leak-proof. Permanent joints are usually leak-proof. To see all topics related to welding, you may browse all welding topics. Skip to content. Home Joining. Welding Soldering Brazing Fasteners including nut-bolt, nail, hook, clip, clutch, button, zipper, etc. Adhesive bonding Resin bonding Cotter joint Knuckle joint, etc.
Topic: Welding — a permanent joining process A permanent joining process does not allow easy dismantling of jointed parts without rupturing them. Which polarity gives better penetration? Which polarity gives maximum deposition rate?
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