Square Butt Joint. Fig. 91.

Material: 1 piece, a, 6" 1 1/2" x 7/8". 1 piece, 6, 41/2" x 1 1/2" x 7/8". A. Fitting the joint: Preferably holding the work as shown in Fig. 34, saw the joint with the backsaw, and block plane it to a perfect fit. Work carefully to a knife mark, and test the work continuously with a try-square to maintain accuracy with both face side and edge.

B. Marking with a knife: If accurate work is desired, never work to a pencil mark, as it is not possible to work as closely to a pencil line as to a distinct cut made with a sharp knife, which gives a definite line by which the joint may be made. If the work requires that a chisel should be used, as in cutting a shoulder, the knife cut makes a definite line in which the edge of the chisel may be placed. Upon this particular piece of work, however, the chisel will not be used ; but the definite knife mark will make possible more accurate sawing, and then all that is necessary to finish the joint is to block plane to the sharp edge indicated by the knife cut.

C. Cutting to length: After a and b are fitted at a right angle, cut off the unfinished end of piece b, block plane it, and make it square with the faces.

To repeat and emphasize a previous statement, the student should learn as early as possible in his work to look ahead to see which pieces should be cut to a neat length, and which pieces should be left long to allow for working. The following is a good general rule to apply to all work, - never cut to a neat length if it can be avoided. Like nearly every other rule, this will demand judgment in its application, or the endeavor to follow it may result in working to a disadvantage. However, it should always be kept in mind when cutting the stock for a piece of work.

The square butt joint is one of the most common forms of construction, as it is the type of joint used where two pieces are butted together at any angle, as outside and inside finish, plain boxes, etc.

Fig. 91. - Square Butt Joint.