This section is from the book "Cyclopedia Of Architecture, Carpentry, And Building", by James C. et al. Also available from Amazon: Cyclopedia Of Architecture, Carpentry And Building.
In Fig. 307 we have seen that the piece D, called the pulley stile, forms one side of the box where the weights for the window sashes are concealed, and that it is fastened to the outside architrave by a tongued and grooved joint. Besides forming one side of the box for the weights, the pulley stile acts as a guide for the sashes, which slide up and down in grooves formed by the outside architrave, the parting strip, and the stop bead, as is shown in Fig. 309. In this figure, which is a section taken horizontally through the window jamb, A is the pulley stile, which should be 1 1/8 inch thick but may be made 7/8 inch thick if the windows are not large. B is the "parting strip," so called because it comes between the sashes and separates them from each other. It is let into the pulley stile as shown, and is usually 3/8 inch thick and about 1 inch wide. It must extend the full height of the pulley stile. K is the "stop bead," so called because it comes in front of the inside sash and holds it in place, forming one side of the groove in which the sash slides. The other side of the groove is formed by the parting strip, as shown in the figure. The stop bead is really a part of the inside finish, and is usually made of hard wood. It is screwed in place so that it can be easily removed, and when it has been taken out the sashes themselves can be removed also. The stop bead must be wide enough to go a little past the edge of the pulley stile and lap over onto the piece L, which is a part of the inside finish called the "inside architrave." The stop bead thus covers the joint between the outside and the inside finish. In Fig. 309 it will be seen that the outside architrave C, the parting strip B, the stop bead K, and the pulley stile A, together form a sort of pocket about the edges of the sashes HH, in which they slide up and down freely but out of which they can not fall either toward the inside or toward the outside of the building. Near the top of the pulley stile there is cut in it a mortise and in the mortise is placed a pulley about 2 inches in diameter, made especially for the purpose.
A stout cord or chain is attached to the side of the sash and passes over the pulley into the weight box, where it is attached to a weight made of cast iron or lead which serves to balance the window sash and make it work more easily. There are two pulleys in the top of the pulley stile, one for each of the sashes. In Fig. 310, which is a view of the upper part of the pulley stile looking at its edge from the outside, one of the pulleys is shown at A. This figure also shows the top of the pulley stile C let into the yoke G about 1/2 inch. This is shown at B. It is the usual method of fastening the pulley stile at the top. In the figure F are the upright studs at the sides of the rough window opening, and E are the rough pieces which form the top of the rough opening. D is the parting strip at both the side and the top of the window opening.
In Fig. 311 is shown a section taken vertically through the top of a window frame of this type. A is the yoke, which should be 1 1/8 inches to 2 inches in thickness; as explained above, it should be long enough to pass over the top of the pulley stile on both sides and allow this member to be let into it. The space K between the yoke and the rough framing EE is filled with rough blocking. F is an outside architrave similar in all respects to that which occurs at the sides of the opening. It is ploughed to receive the yoke, as shown. B is the parting strip, the same size as that on the pulley stile described above, and C is the stop bead. L is the inside architrave. EE is the rough framing between the studding at the sides of the opening, G is the outside boarding, and H is the plastering inside, D being what is known as a "ground."
Fig. 309. Section Showing Pulley Stile Construction.
In Fig. 312 is shown a section taken vertically through a window sill, showing the sill complete. Here A is the sill itself, which will be seen to extend through the wall far enough to receive the inside sash G. The top of the sill is cut with a slope downward and outward, which is known as a "wash," and the purpose of which is to carry off the rain water which may be driven against the glass of the window and drip down from there to the sill. C is the outside boarding, B is the rough framing, and E is the plaster. D is a part of the inside finish called the "stool" and F is another piece called the "apron," which together cover up the edge of the sill on the inside. The pulley stile is let into the sill about 1/2 inch in a manner similar to that in which it is let into the yoke at the top, and the sill is made long enough to extend a little beyond the back of the pulley stile on both sides just as is the yoke. Thus the two pulley stiles at the sides and the yoke at the top, together with the sill at the bottom, form a complete frame called the "window frame," which is usually made up at the mill and taken to the building in one piece, where it is set up in place inside of the rough-framed opening. The slight rabbet in the sill shown at H is intended for a stop for outside blinds when these are used. In this case the blinds are hung as shown in Fig. 313, which is a section taken horizontally through the window jamb. A is the outside architrave, which is placed in this case outside of the outside boarding B for the purpose of receiving the blinds. It serves at the same time as a stop for the wall covering C. D is the blind. and E is a piece put in to form the weight box and known as the "outside casing." This figure also shows at G a small block which may be inserted between the outside casing and the sash F in order to fill up the space and push the sash nearer the inside wall line. To this small block a strip may be nailed which will take a sliding fly screen.
Fig. 310. View of Upper Part of Pulley Stile.
Fig. 311. Vertical Section of Top of Window Frame.
Fig. 312. Section Showing Sill Construction.
Fig. 313. Horizontal Section through Window Jamb.