• A mortise and tenon joint is strong and durablemur grange image by musicorso from Fotolia.com
  
  Mortise and tenon joints are made by cutting a hole into one piece of wood and cutting the end of another piece of wood so that it fits into the hole. These joints, particularly when strengthened by a peg driven through both pieces of wood, are very strong and durable and have been used in furniture building for hundreds of years. The most important aspect of a mortise and tenon joint is that it fit together snugly but not be so tight that it cracks the piece of wood into which the tenon is driven.
  
  

Measuring for a Tenon

• Measuring for a tenon needs to be very accurate for it to be effective. The best tools for this are a precision ruler, a cabinetmaker's square and a very sharp awl. For a 1-inch-long tenon, use the ruler to measure exactly 1 inch from the end of the piece of wood. Lay the cabinetmaker's square across the piece of wood, perpendicular to the direction of the measurement that was just taken, and draw the awl across the piece of wood to incise a line. Continue this line across the remaining three faces of the wood. This leaves you with an incised line around the piece of wood that shows where the shoulder of the tenon will be.
  
  

Making a Tenon by Hand

• Cutting a tenon by hand requires a back saw, a very sharp chisel and a good eye. A back saw is so named because it has a back, a larger piece of metal that runs along the rear edge of the blade to make it rigid. Because of this piece of metal, a back saw can't be run all the way through a piece of wood. It is made specifically for cutting shallow kerfs such as are made when making a tenon. You will need to mark the shoulder depth of the tenon before cutting with a backsaw. For example, if the piece of wood is 1 inch thick and you want a ½-inch tenon, you will need to cut ¼ inch into the wood on both faces. Make a mark ¼ inch down with the awl and very carefully cut down to that point with the backsaw. When all the shoulders have been cut, pare the tenon down to thickness with the chisel, checking frequently for fit with the mortise.
  
  

Making a Tenon with a Machine

• Tenon making is easier with a machine due to the ability to make preset depths. Cut a tenon with a table saw by laying the piece of wood into a crosscut cradle, setting the saw blade height so it will cut the desired size of shoulder and then running the piece of wood through the saw. Once the shoulder cut has been made, the waste wood can either be cut off with the chisel, as with the hand method, or the piece can be run through the table saw repeatedly, moving over the width of the saw blade each time and thereby removing all of the waste wood. Professional shops that make large numbers of tenons sometimes invest in dedicated tenoner machines with adjustable heads that can cut a tenon in a single pass.