This section is from the book "Spons' Mechanics' Own Book: A Manual For Handicraftsmen And Amateurs", by Edward Spon. Also available from Amazon: Spons' Mechanics' Own Book.
The construction of the frame of a chair has already been described (Figs. 689-95, pp. 363-9). The first step is to tightly strain 3 lengths of webbing (No. 10 or 12) across the seat from front to back, and 3 from side to side, securing it to the bottom of the frame with 5/8-in. tacks. Next distribute the 5 springs (6 in.) diagonally and equidistantly over the scat, and fasten to the webbing with medium twine. Knot some lashing cord to the top ring of each spring, and tie them all down to about 4 1/2 in. high, taking care that they are quite upright in their places. Fasten a breadth of canvas taut across the springs with 5/8-in. tacks, and, with a bent needle, sew the canvas to the top rings of the springs (still keeping them upright) with 5 equally divided stitches, knotting each separately.
Before the first stuffing is commenced, a string is run round the edge of the seat, and a. moderately full body of hair is picked or strung on, avoiding too much in the middle; scrim (very coarse muslin) is next laid over the hair. Keeping the bridle square with the chair, temporarily tacked into place, and fastened to the canvas on the springs by a double-pointed needle, making 3 rows of stitches 3 in. long and 4 in. from the outside edge. Next, this outer edge has to be firmly filled in, so that after the scrim has been secured with 1/2-in. tacks all round, and stitched all over, the stuffing should rise about 3 in. above the frame, presenting the correct outline of the seat, and slightly overhanging.
To begin the second stuffing, mark a line down the centre of the seat from front to back, and mark the places for 10 buttons, putting alternately 3 and 2 in a row, commencing with 3 in the front, and allowing none to be less than 3 in. from the edges of the seat. At each button, a small hole is made with scissors through the scrim, to fix the spot. The skin for covering the seat is next placed with the neck to the back, and marked as shown in Fig. 732, a being the central line, b the plaits, and c the spots for the buttons, which may be 1 1/4 to 2 1/2 in. apart, according to the degree of fulness desired. The skin being filled, the hair for the second stuffing is picked on with care, so that the leather may be rilled out firmly and free from creases; then the wadding and the skin are put in place, and the buttons are inserted with a slip knot of button twine and pulled halfway down, taking care to slope the hair away from under the buttons; the knots are then tied, the ends are cut off, and the plaits are worked out smooth.
Work the fulness of the stuffing into the outside plaits that are square with the seat, and pin the skin to the edge of the first stuffing.
In cutting off the skin to the exact form, which is the next step, about 3/8 in. must be allowed for turning in. It is well to secure the outside edges of the plaits by an occasional stitch. The margin cut off all round the skin will be available for the border and welt, for the latter of which lashing twine is used. The 2 joints necessary in the border should come about 1/2 in. from the front corners on the sides, the jointing being effected in the following manner. With a very sharp knife, the border is cut quite straight, and the ends to be joined are chamfered off so as to overlap each other about 1/2 in.; the joints are made fast either by curriers' paste or by nearly cold glue: both will make ineradicable stains if they penetrate the leather, as they will do if hot. When the joints have dried tight, the border is strained into place and temporarily pinned on, 2 or 3 corresponding little notches being snipped on the border and seat in front and at both sides, as a guide in the sewing. The strip for the welt is cut and joined in the same way. After both border and welt have been dried and sewn, they are turned up and stitched to the edge of the leather seat. A little piece of buckram tacked on each front corner assists in preserving a proper outline.
When some wadding has been stuffed under the border, it is fastened with 3/8-in. tacks, without creases. If studs are added with banding, they should be about 1 1/2 in. apart; if close studding is adopted, no band is needed. It is only when springs are employed that canvas is used on the bottoms; and the average quantity of hair used is 2 1/2 lb., whether it is a spring seat or not.