Doweled Joint. Fig. 128.

Material:

1 piece, 6" X 1 1/2" X 7/8". 1 piece, 4 1/2" X l1/2" X 7/8".

If this joint is well made and not exposed to the weather, it is the most efficient substitute for the mortised joint, and may in general be used in any place where a mortised joint would be suitable; under certain conditions it is a stronger joint than that for which it is a substitute. For 7/8" material, a §" dowel should be used; but for anything thicker, a 1/2" dowel is generally necessary to give the desired strength. In doweling thick material, the dowels should be placed as shown in Fig. 129.

A. Marking for dowels: Method 1. The utmost accuracy is necessary in marking the centers of the holes and boring them, if satisfactory results are desired. The principal application of this method is in doweling the joints of a wide board.

1. Place the two pieces in the exact relative positions that they are to occupy permanently, as at A, Fig. 130.

Fig. 128. - Doweled Joint.

2. Make a pencil mark across the joint upon the faces of both pieces at once, as at aa.

3. With either a pencil or knife, square across both edges of the joint from the marks, as at bb of B.

4. With a sharp gauge, make mark c, which crosses bb. The intersection of these two lines gives the center of the hole, or the point at which the point of the worm of the bit should be placed.

5. A scratch awl should be used to make a small hole at the above described point, so that the bit will enter accurately, as otherwise it is apt to enter a little to one side of the intersection, or to follow the grain. The reason for this will be apparent if the point of the worm is examined, since it is the point of a spiral; hence, the point will have a tendency to push to one side when the worm enters the wood. Bore 3/8" holes 1" deep, and fit the dowels so that they may be pushed in with the fingers.

Smooth and sandpaper both pieces at once after the joint is made. Do not glue together.

Doweling an edge joint: In laying out dowel holes in preparation for gluing up a wide board, many workmen prefer an application of Method 1, and for medium-sized work it is quite as practicable, and often faster. Place the two pieces, as shown in Fig. 95, with the face sides out, and square across the edges of both pieces at once. With a gauge, working from face sides, mark the distance from the face of the board to the center of the dowel holes, and proceed as in the previous problems.

Length of dowels: It is not wise to use a dowel longer than is necessary ; one extending from 3/4" to 1 1/4" each side of the joint will hold as well as one reaching farther into the edge of the side wood, for the reason that the wood between the joint and the end of the dowel will shrink, and the longer the dowel, the greater the width of wood there is to be affected. A longer dowel may sometimes be necessary in the wide stile of a door, to give sufficient strength to resist the slamming which a door receives. A dowel should be at least 1/8" shorter than the aggregate depth of the holes which are to receive it, and should be made loose enough to be pushed in with the fingers, but not loose enough to fall out or to be rattled around. The ends of the dowel should be pointed, as at C, Fig. 130. This allows some of the glue to be forced up between the dowel and the sides of the hole, and not all pushed before the end of the dowel, which would be the result if the dowel were square-ended; unless the dowel were too loose, in which case it would not have its full strength, as the joint would not be wood to wood.

Fig. 129. - Dowels in Thick Material, Placed Staggering.

Fig. 130. - A, B, Marking for Dowels: Method 1. C, Pointed Dowel.

Uniformity: In boring holes for dowels, it is the custom of many workmen to use one of the many forms of bit stops upon the market, in order to insure a uniform depth to all of the holes; others count the turns of the bit, from twenty to twenty-five giving the desired depth. This uniformity is necessary, otherwise the dowels will have to be cut to different lengths, which will require care and time to locate in their proper holes while the joint is being glued up, just when every second of time is precious.

Comparison of the mortised and the doweled joint: As compared with a mortised joint, when used upon common doors, the dowel is not so satisfactory as the mortise, because the tenon reaches through the stile, and the glue, collecting at the joint as the pieces are brought together, makes a stronger connection there than at the end of the tenon at the outside of the stile; therefore, when the stile shrinks, it usually holds at the joint, and its outside edge draws toward the joint, allowing the end of the tenon to project beyond the stile the amount of the shrinkage. In a doweled door, the joint would probably open.

The material used in making the ordinary grade of commercial doors is apt to be less thoroughly seasoned than it should be, and, as a rule, there are not enough dowels used to give the joint its maximum strength. Moreover, the dowels are generally placed in a straight line, instead of "staggered," as shown in Fig. 129.

If a door which is exposed to the weather is properly doweled, it will stand better than a mortised door in which the tenon passes through the stile, since in the latter case the moisture will quickly find its way into the end of the tenon, and the door will be rapidly destroyed. The mortises of an outside door should be of the type known as " blind," or " fox wedging," Fig. 141,.as in this way the end of the tenon is protected from the weather.

When used upon furniture and other work which is set up in a warm shop, and when made of thoroughly kiln-dried lumber, a properly made doweled joint is perfectly satisfactory.

B. Gluing the dowels: The glue should be put in the hole, and not on the dowel; otherwise it will be scraped off as the dowel is pushed into its place, unless the latter is fitted very loosely, in which case the glue will soak into the end wood of the pieces being glued together, not leaving enough to hold the dowel firmly. The joint should be well fitted before the glue is applied; it should be forced together, and held in place by clamps until the glue has set. In preparing for gluing up wide boards, which are to be doweled, apply Method 1 of marking for dowels.

C. Marking for dowels Method 2. This method of marking for dowels is sometimes used when it is not practicable to use Method 1, as in doweling irregular forms. See Fig. 131.

1. Drive small brads, c, straight into the end of piece a.

2. Cut off the heads of the brads at about 1/8" from the wood.

3. Move piece b against a, being careful that the outsides are in just the right relation to each other, and apply enough pressure to make the brads leave imprints, d, in the end of piece b. These are the centers of the dowel holes.

4. Pull the brads out of piece a; the holes thus made are the centers of the dowel holes in that piece.

D. Marking for dowels: Method 3.

If it is desired to dowel irregular forms, or to make a number of joints just alike, this method will not only give good results and save a great deal of time, but the pieces just alike will be interchangeable.

Fig. 131. - Marking for Dowels: Method 2.

1. Use of the templet: Make a templet of pasteboard; or, if it is to be used indefinitely, of tin or zinc, as shown in Fig. 132, and through it prick small holes in the position which will denote the exact centers of the desired dowels, as at a.

2. Place the templet upon the end of piece b, with the corner c of the templet at c of piece b, and flush with the face side; with a pricker, mark through the holes of the templet the centers of the dowels, 1, 2.

3. Place d of the templet on the edge of /, and flush with the face side, so as to' coincide exactly with d of piece f. Through the holes a a of the templet, mark 1, 2 upon the edge of piece /. This method is much used upon large or irregularly shaped work of all kinds, as it permits of accurate work, and needs no tools but the templet and the pricker. The ends of the templet need not be turned over, as indicated, except for the purpose of making more rapid work possible.

Fig. 132. - Marking for Dowels: Method 3.