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Our Ballerina was very happy!
CHAIR PRODUCTION
Coil Springs were selected for gauge and stiffness; the decision based upon comfort and general longevity. A balance was struck between the two criteria, and a medium gage steel spring was chosen. The layout of the springs was taken into account as well. Mitchell experimented with the spring layout in our Ballerina’s Chair. He began with four rows, shown directly below, and ended up with three rows, which allowed him to tie an 8-way tie for longevity, but have the desired drop due to fewer springs – our Ballerina wanted to sink into her comfy chair! The springs were secured to the webbing, below.
A 4-way tie knots the spring’s twine onto four positions of the top orbit of the coil funnel. The knots are securely placed in four perpendicular positions: 12 o’clock, 6 o’clock, 3 o’clock, and 9 o’clock. The 4-way tie is generally used when:
Doubling the twine on a 4-way will nearly double the life span of the spring ties if tied properly, while still giving a soft drop. A good 4-way tie will last for 20-25 years An 8-way tie also knots in the diagonal directions (1:30, 4:30, 7:30, and 9:30) between the four horizontal and vertical directions, supporting the spring at eight points around its circumference. This procedure ensures that the spring cannot pivot independently in any one direction. When the spring compresses in a downward or lateral direction, it borrows support from its neighboring spring, which is also supported at eight points and borrows support from its neighboring spring, etc. This way the entire spring deck acts as a unit, with each spring borrowing force from its neighboring spring. An 8-way tie is preferred when firmness and longevity is the priority. An 8-way tie, especially if the spring tie twine has been doubled, can last many years under heavy use. It is not unusual to see a double 8-way tie function without breakage and excessive stretch for 50-75 years or more! Mitchell chose to tie a double 8-way tie, which gave the tie greater strength and longevity.[2] Spring twine was cut after the springs were anchored to the webbing. Mitchell generally cuts his spring twine five times the length from front to back; in this case, since he was tying a double-8-way tie, he doubled his twine length. All knots were overhead thumb knots unless otherwise stated!
The next knot brought the two pieces of twine back together at the second position, 6 o’clock, on the rear spring. They were knotted as if they were proceeding toward the middle spring (the second spring) in front of it. This tie also knotted at the 12 o’clock position of the spring orbit, and the spring is set at the level determined to be best for the desired seat deck level. Next the double twine separated once more and dropped to the second and third orbits of the same spring (second spring), at the 6 o’clock position. This stabilized the center position of the spring funnel, which is the midpoint and center of gravity. This tie ensured that the spring would not buckle at its center, since it is the spring which takes the greatest backward stress.[3] The front row spring was ready to be tied. The front row spring is always the most vulnerable to spring twine abrasion because it is so close to the front seat rail. Also, the front spring receives the greatest amount of downward thrust. Therefore, careful attention was paid to supporting this spring, not only at all points of the clock on top of the funnel, but also at the 6 o’clock and 12 o’clock positions on the internal funnel. Also, because the ties coming forward off the front spring needed to anchor to the front wood seat rail, extra care had to be taken to wrap these ties by whipping the four anchoring ties together into a hangman’s loop. This was done so that the sharp wooden edge would not abrade or cut these main supports over time. As the two lines proceeded forward from the middle spring, which was tied at the second and third rung positions of the funnel, a tie was also placed on the second and third rungs at the 12 o’clock position, ensuring that the back side of this spring pulled down no more than an inch above the established deck level. The two pieces of twine proceeded forward to the 6 o’clock position, to tie at the third and fourth rungs of the spring funnel. Finally, they were pulled forcefully toward the front rail, bringing the center spring funnel within 1 to 1 ½-inches of the rail. They were anchored to their respective nails and hammered into the hardwood front rail. A knot was secured to the nail before the nail’s final setting, ensuring that the main tension line was below the knot. This allowed the main tension line to be protected from the sharp edges of the nail head. All knots securing twine to the nail are overhand thumbknots unless stated otherwise. At this point, the forward and backward spring forces were established. Final vertical front levels were not yet set, nor were the front two springs secured to one another at the top of the spring. The next several steps bound all front to back and back to front forces together into one cohesive vertical line. We now had two long strands of twine nailed to the front seat apron directly in front of the front coil spring of our middle spring row. Only one of these strands traversed back toward the rear spring row.
His return path of spring knotting was the same path from which he came:
Mitchell reversed his knotting direction and went toward the 6 o’clock position of the middle spring. He placed his knot and then proceeded forward to the 12 o’clock top rung position of the front spring. Instead of knotting this spring he looped his twine over the top and around this spring one-hundred-eighty degrees, heading back toward the 6 o’clock top rung position of the middle spring. Next, he looped the twine back over the top of the middle spring’s 6 o’clock position, and headed back toward the front rail, again, one-hundred-eighty degrees. The twine was loosely looped between these two springs. As he began to pull and tighten his line, these two springs began to straighten up into a stable vertical position. He pulled until they reached the desired height, and then knotted his line at the top rung 6 o’clock position of the middle spring, taking care to whip the knotting twine around the four strands of twine, which comprised the fulcrum. The middle spring at 6 o’clock and front spring at 12 o’clock were stable. Mitchell continued forward with the line to the 12 o’clock position on the top rung of the front spring and secured it with a knot, then dropped the line through the interior of the front spring, and pulled the top of his spring downward to a level deck position. He placed a secured knot on the third rung at the 6 o’clock position of the front spring. Mitchell then brought the twine forward to the frame, and knotted it to a nail. Once it was secured to the frame, he returned back to the fourth rung position on the front spring, knotting and then looping the line around several strands of twine coming off the third and fourth rung positions of the front spring. He continued to loop tightly around these strands, pulling them together. He proceeded this way all the way back to the wooden frame; then he knotted and nailed it to the wooden front frame. The third and fourth rung positions of the front spring now act as one unit. The looping technique created the appearance of a hangman’s knot, approximately ½-inch thick. This protected all the front tension lines from abrasion. Now we were ready to set the front edge. Mitchell had two uneven long strands of twine dangling off the front seat rail. He lifted the shorter, left twine strand upward to the top rung of the front spring at the 6 o’clock position, crossing laterally, approximately 1-inch to the right of spring center. He placed a tight clove hitch knot, which allowed the front spring to still pivot without coming undone. He lifted the right, longer stand upward in the same fashion, crossing over the top of his last strand laterally and to the left, approximately one inch. He placed a clove hitch locking knot at the top rung. These two strands now created a “V” pattern from the frame, coming to a point on the front spring. His two previously separated strands of twine were now reunited, and the front spring edge was pulled down to a level position with the rest of the spring deck. Now he took his two strands and knotted them together at the top rung, 12 o’clock position, of the front spring. Proceeding toward the rear of the seat deck, he double knotted the top at the 6 o’clock and 12 o’clock positions of the middle spring, and finally finished off with a triple knot at the 6 o’clock position of the rear spring. The double front rear tie was now complete. This is an extraordinary way in which to unify all the competing forces of the springs into one unit. Once all the vertical spring lines had been tied in this fashion we were ready to proceed to the horizontal spring rows, moving right to left, and tying them in the same basic manner as the spring rows from rear to front.
Mitchell cut his twine twice the length of the seat frame; then doubled this length. (Remember, he was tying a double 8-way tie.) Starting at the right side seat rail where the front spring row was located, he tacked the midpoint of the doubled twine at two points, 1 inch apart, using #8 1½-inch long polished nails, making sure he looped the two tension lines under the string so as to protect them from the nail top. Mitchell took his two lines and separated them, then tied them to the top and second orbit of the far right spring. (Detailed picture not shown.) This allowed for the right front spring to be supported all the way down the tension line of the spring. Then he proceeded to the 9 o’clock position of the right front spring and knotted both strands of twine together. This process was the same for the middle spring, knotting at both the 3 and 9 o’clock positions. The left front spring was knotted at the top rung in the 3 o’clock position; then the doubled twine was dropped down to the second rung in the 9 o’clock position. Finally, he pulled the spring twine tightly and nailed both strands to the top of the seat rail frame, on two separate nails. One strand was knotted and terminated at this time, and then nailed it to the frame. The other strand was pulled up to the top of the left front spring and tied on the top rung at the 9 o’clock position in a clove hitch, allowing the spring to be stable and still pivot. Mitchell secured his final strand at the 3 o’clock position of the left front spring, using a double locking knot, and cut off the excess twine. Mitchell continued this process from right to left across all the horizontal rows. When he was finished, he had a spring deck that was unified in the vertical and horizontal directions. This is a basic 4-way tie! Notice the even spacing achieved in all directions of the 4-way tie? This is important, especially if you are going to continue into an 8-way tie. A 45° angle can be drawn through the rows, meaning it will be easy to make the diagonal ties without having to correct the spacing on the vertical and horizontal ties by pulling them one way or another.
He began by cutting single strands of twine 1½ times the length of the diagonal line he was about to tie. A metal straight edge was laid along the diagonal line to be tied, and marked the spots where the nails would be placed at each end. He drove two nails halfway into the seat rails at the marked spots, knotted the end of the twine around the nail at the back seat rail, pulled it tight, and then hammered the nail fully into the rail. Mitchell proceeded forward and diagonally, securing his first knot on the second rung at the 1:30 position of the rear spring with which he was beginning. He pulled the twine until the spring funnel was straight along its horizontal axis, and then brought his twine up to the top rung of the same spring at the 7:30 position, and tied a knot. He followed this same process along the diagonal line through the last spring in the line, dropped down the last spring funnel in the line, straightening the funnel and tightening the line as he went. He wrapped the twine around his preset nail, securely knotted the twine, and hammered the nail into the rail. He trimmed of the excess line. Mitchell proceeded to the next line of diagonal springs until all rows were tied in the right-facing 45° diagonal. He moved to the ties from back to front in a 45° left angle, substituting 9:30 positions for 1:30 positions, and 4:30 positions for 7:30 positions. When finished, all springs in all rows were tied in eight directions symmetrically around the coil. This unified all major and minor forces into one supporting unit, allowing the sitter to move in any direction and feel support. Notice the twine lines tied between the rows of springs, above? On 4-way or 8-way ties, Mitchell chose to give additional support to the tied horizontal and vertical lines, which move between the springs and are vulnerable to stretching over time. The manner in which a person sits, favoring one hip or the other, cross-legged, plopping into the seat, etc., all contribute to how a spring seat evolves and matures. Tying the horizontal and vertical lines between the springs usually will offset many of these anomalies. Mitchell worked from back to front, cutting the twine 1¾ times the length of the distance between the front and back rail. Again, he preset the nails halfway into the back and front wooden rails, at the midpoint between the rows of springs. He looped the twine around the first nail in the back rail, knotted it, pulled it taught, and hammered the nail into the rail. Coming forward, he knotted his first tie midpoint around the rear row of twine running through the rear row of springs; then did this all the way through the rows of springs to the front row, and knotted the twine similarly to the rear in an overhead thumb knot.
This spring deck will last for decades! Click here to view more of the Buildup!
[1] Please excuse the changing color pink in our process photos - we were concerned with showing other aspects, so the lighting used was relatively unconcerned with the accuracy of the pink color! [2] Note: The Ballerina Chair utilizes three horizontal rows of springs from back to front, but often a spring-up will require four or even five rows of coil springs. The tie procedure is the same as a three row, except the third and even fourth middle rows (counting back to front in a four and five row spring-up) would not be focal points for the added tie support, described below, and would not receive the same kind of attention as described in detail in this three-row spring-up. In terms of the vertical rows, it is the same: We have three rows across on the Ballerina Chair, but if you were doing a couch and had ten rows, the two anchoring springs of each row at each end would be treated as described in this section. [3] Note: In the case of a five row spring-up, the critical points, from back to front, would be the first, fourth and fifth springs.
Contact Information
©Mitchell Powell Furnishings
Clipart graphics from Microsoft
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