Halved Scarfed Joint. Fig. 109.

Material: 2 pieces, 6" X 1 1/2" X 7/8".

A. Fitting the joint: This joint is sometimes used when it is necessary to join two timbers lengthwise. If used as a girder, there should be a support under the joint at d. This form of construction is sometimes fastened together by the same methods as shown in Fig. 108.

1. Lay off the shoulders of the joint, say 2"', by a distinct knife mark upon the face, or top edge, of piece a, at c, and upon the back, or bottom side, of piece b, at d.

Fig. 108. - Method of Holding Finished Molding in a Vise.

Fig. 109. - Halved Scarfed Joint.

2. Square from these marks, with a knife, a little less than half of the thickness of the piece upon each edge.

3. Set the gauge to the distance e, which should equal half of the thickness of each piece, and mark plainly from the face side upon the two edges and across the end of each piece.

B. Cutting to a knife mark with a saw: With a backsaw, cut to the gauge mark from the face of a and the back of b. Place the pieces one at a time in the vise, and with the backsaw cut out the recess between c and d, and their respective ends, which will allow the pieces to come together. If this is done with sufficient accuracy, the faces will fit and be flush (even). The saw cut should be made with such accuracy, that one half of the knife and gauge marks will be left upon each of the two pieces that are to form the joint, in which case, all that will be necessary to make a perfect fit will be to trim the joint a very little with a sharp chisel.

C. Fitting with a chisel: If any fitting of the shoulder is necessary, do not do it by guesswork, but make a distinct and accurate knife mark at the exact place required to make a perfect fit. In trimming to this mark, grasp the chisel as shown in Fig. 110, not as in Fig. 1ll, which is extremely awkward and inefficient. If the chisel is used as in Fig. 110, very little strength is necessary, as the pressure of the shoulder does the cutting.

Fig. 110. - Correct Use of the Chisel in Fitting a Shoulder.

Fig. 111. - Incorrect Use oF the Chisel in Fitting a Shoulder.

Fig. 112. - Incorrect Use of the Chisel in Following a Line.

In fitting a joint of this sort, it is best to "cut under"; that is, to cut the wood inside of the visible part of the joint a very little back of the line, so that nothing will prevent the joint from coming together.

Never try to follow a line by using the chisel as in Fig. 112, as the chisel is apt to run into the shoulder beyond the line, its bevel giving it a tendency to "lead" back of the knife mark which indicates the shoulder, thus destroying the joint. The visible portion of any joint should be as nearly perfect as possible; therefore in this case, the longitudinal portion should be perfectly straight, or slightly hollowing.

Glue the pieces together, using hand screws to hold them in place each way. Cut the model to desired length, and smooth and sandpaper.