Class 7.

THE machines in Class 7 are provided with large long-beak shuttle and powerful mechanism for the strong lock-stitching of heavy fabrics of all kinds, not exceeding &-inch in thickness; they have sixteen inches of clear space from needle to base of arm. The varieties of this class, numbered from 1 to4, both inclusive, have plain presser-feet and drop-feed. The extreme length of stitch made on these four varieties is onehalf inch; various sizes and forms of feed are used, as best suited to the work to be performed.

Machine No. 7-1, illustrated above, is fitted for operation by foot-power; the stand can be provided with either rocking or revolving treadle; the latter enables the operator to stop or start the machine without touching the balance- wheel and to run at high speed without great exertion. The balance-wheel used with the revolving treadle on Machine No. 78-1 is fourteen inches in diameter, its momentum promoting ease of operation and steadiness ot motion; it carries pulleys for two changes of speed. For the ordinary rocking treadle the balance-wheel is ten inches in diameter.

Machine No. 7-2 carries a smaller balance-wheel arranged for mechanical power communicated through the Singer Under-driver, and is therefore provided with but one pulley for driving belt.

Machine No. 7-3 is fitted for operation by mechanical power communicated through the Singer Friction Driving attachment and Machine No. 7-4 receives motion by means of flat belt running over tight and loose pulleys on the machine and is provided with our convenient form of belt-shifter.

All the machines of Class 7 are fitted with presser-foot having unusually high lift; they carry very coarse thread and are pre-eminent for strength and efficiency in the accomplishment of strong stitching of heavy material such as Leather, Canvas, etc.; they are so built in every point as to perform the greatest amount of work in the best manner and with the least expense for repairs.

Among the many articles manufactured on the machines of Class ? may be mentioned the following as indicating the range of their capacity: Leather and Canvas Mail Bags, Trunks and Valises, Harness, Horse Brushes, Carriage Work, Belting, Sails, Tents, Carriage Tops, Camel's-hair Strainer-cloths for Chemicals, Canvas Strainer-cloths for Oil Refiners, Cushions, Hassocks, Jute Bags, Book and Pamphlet stitching, etc.

On the following pages will be found illustrations and descriptions relating to the varieties of this class, numbered from 5 to 22, both inclusive, showing more particularly their special features and stating some of the principal uses for the respective varieties.

The preceding general description of machines in Class No. 7 applies to the varieties of this Class numbered from 5 to 8, both inclusive, excepting that the latter are provided with the Vibrating Presser illustrated above; by the use of this presser a uniformly strong and perfect feed is secured with fabrics having rough, uneven or adhesive surfaces, with soft goods liable to pucker or in stitching around curved edges.

Machine No. 7-10 is extensively used for Harness manufacture; it has drop-feed and an adjustable presser which may be used either as a vibrating or a plain presser as best adapted to the work

Machine No. 7-22 has the same form of adjustable presser as No. 7-10, but has two needles and two shuttles for making two independent lock-stitch seams at one operation, thus adapting it for the manufacture of articles requiring great strength of seam or where the stitch has to be made through several plies or thicknesses of heavy material, as in putting on strips over seams and stitching on handles for Coal and Ballast Bags, or in strip-stitching any heavy fabric. The distance between needles is gauged, as ordered, from 1-inch to 1 inch, using; box shuttle, and from 1 inch to 1 1/4 inch, using a cylinder shuttle.

Machine No. 7-9 corresponds in its general form and efficiency of opera- tion to all others of this class, but differs in the fact that it is provided with Alternating Pressers. This device comprises two pressers acting separately and alternately; the first moves forward with the feed, is then lifted and returned to its position; the other holds the material down while the first rises and until it descends upon the fabric, but is raised while the material is carried by the feed. Each presser, while resting upon the work, forms a fulerum upon which the other is raised, consequently the height of their movement always corresponds to the thickness of the fabric, thus allowing the free passage of material which varies in thickness and securing the perfect formation of the stitch.

By the use of this device two or more pieces of material are moved with perfect uniformity so that their edges are even at the completion of the stitching.

Machines of Class71, having this form of presser, are extensively used in the manufacture of Burlap Bags, Furniture Cushions, Cushions for Railway Cars, Leather Work for Carriages, etc.

Machine No. 7-11 is especially designed for Book-binders' use in " Single Strip" stitching, in which service it has proved to be of remarkable efficieney in stitching a specially prepared strip to the various sections of a book preparatory to binding.

Guides are provided for the accurate delivery of the strip under the centre fold of the section to which it is stitched for the purpose of strengthening the fold and increasing the flexibility of the book.

The length of stitch is adjustable up to one inch and the formation of stitch is so regulated that both the down and the up-take of thread through the needle-hole is accomplished while the needle is out of the material, thus enabling the use of thread sufficiently large to entirely fill the needle-hole and a perfect stitch having the greatest strength is thereby obtained.

A feed-reversing lever is provided for operation by knee-pressure, so that either one or both ends of the seam may be readily double-stitched for the purpose of securing the thread and strengthening the work.

The machine illustrated above is for Book-binders' use in "continuous strip" stitching; the strips are used in specially prepared sheets which are fed in exactly the proper position by means of grooved top and bottom guides.

The illustration shows the arrangement of these guides, which are especially adapted for the accurate and effective performance of this work; this device is of the highest efficiency and is in extensive practical use by the largest book-binding establishments.

Machine No. 7-14 has no under-feed, being adapted especially for heavy leather stitching. The movement of the material is obtained through top and forward pressure applied to its upper surface by a special device used in place of the ordinary presser-foot. This device is furnished with a set of changeable presser-points making respectively 8, 10 and 12 points or stitches per inch These points, acting as a feed, also set up the stitch, giving it a very superior finish and leaving the leather without feed mark on either side.

The movement of the presser-points is communicated from a cam on the main driving shaft to one end of a parallel shaft which engages the pivoted presser-bar when in contact with the material and at the instant when the needle is withdrawn, thus causing the bar to swing and move the material a distance corresponding to the length of the stitch.

The range of work accomplished by Machine No. 7-14 is indicated by the fact that it is extensively used for the manufacture of Heavy Traces, Horseshoe Pads, Trunk-handles, Foot Balls, Punching Bags, Leather Covers on iron rings, etc.

The size and proportions of the No. 7 Machine peculiarly fit it for heavy work and the space under the arm makes it especially convenient for book-binders use.

Machines No. 7-13 and No. 7-15 have Vibrating Presser and the feed is adapted to make any length of stitch up to one inch, the capacity in perforation of paper being up to five-eighths of an inch in thickness; a presser-foot of special form is provided for the most effective manipulation of paper, and for securing greatest efficiency in book, magazine and pamphlet stitching.

Machine No. 7-15, illustrated above, is fitted with tight and loose pulleys and our convenient form of belt-shifter; Machine No. 7-13 has the Singer Friction Driving attachment.

FOR STITCHING HEAVY BAGGING.

The machines of Class 7, having the variety numbers 16, 17 and 18, are especially adapted for the manufacture of Bags for Cotton-seed Compressers, for the carriage of heavy weight and similar uses where great strength of seam is required.

These machines use either a heavy Cotton, Linen or Camel's-hair thread, the size and shape of needle being especially designed for such use: the thread take-up is provided with a roller over which the thread is carried in order to prevent chafing.

The length of stitch is one-quarter inch and a No. 14 needle is used. Machine No. 7-16 has plain balance-wheel to receive power from an under-driver; Machine No. 7-1? has the Singer Friction Driver and Machine No. 7-18 has tight and loose pulleys and belt-shifter for flat belt.

There are three varieties of top-feed machines in Class ? that are especially adapted for the manufacture of oval Leather-back Brushes and similar work where it is required that strong stitching shall be performed close to the edge of objects having irregular shape.

To enable the convenient and efficient performance of such work the bedplate is eut away close to the needle, as shown in the machine illustrated, which is intended for mechanical power and provided with the Singer Driving attachment.

Machine No. 7-21 has tight and loose pulleys for flat belt and our regular belt-shifter; Machine No. 7-19 is for foot-power and is provided with a heavy balance-wheel having pulleys for two changes of speed; it is operated on a stand having revolving treadles as previously illustrated and described on page 94.

The following is lifted from John Langdon's Comprehensive Model List

7 (class)		Industrial	Large machine (bed = 25 1/4" long x 10" wide). Space to side of needle 15 7/8". Long beak oscillating shuttle. "Not as heavy as Class 6...". For sails, tents, covered wagons, tarpaulins, carriage trimming, etc. in leather, paper and canvas. Made in Elizabethport only.	-
7SS		Industrial	Single thread chainstitch for blindstitching; hemming dresses, blouses, skirts, etc. Narrow cylinder (diam. 1 3/4"); swing-out work plates for flat or tubular work. Oscillating looper. 3 to 8 stitches per inch. Speed 2500 spm.	Cat. 7425-61 also 3690 (short point) or 7425 (long point)
7-1		Industrial	Drop feed. Two speed pulley for foot treadle operation.	7x1 or 7x2 (leather)
7-2		Industrial	As 7-1 but with balance wheel for power table.	7x1 or 7x2
7-3		Industrial	As 7-1 but with S.D.A.	7x1 or 7x2
7-4		Industrial	As 7-1 but with belt shifter.	7x1 or 7x2
7-5		Industrial	Drop feed. Vibrating presser. Two speed balance wheel. Foot treadle. For heavy bags, carpet mitres. Horse collars. Harnesses; sails etc. (In catalog 09/1951)	7x1 or 7x2
7-6		Industrial	As 7-5 but with balance wheel for power table.	7x1 or 7x2
7-7		Industrial	As 7-5 but with S.D.A.	7x1 or 7x2
7-8		Industrial	As 7-5 but with Belt shifter.	7x1 or 7x2
7-9		Industrial	Drop feed; alternating pressers. S.D.A. 'Light running' machine for moderately heavy goods.. Can be fitted for foot treadle or power table.	7x1 or 7x2
7-10		Industrial	Drop feed; adjustable presser feet - either vibrating or stationary. For cloth or leather. Foot treadle or power. Can be fitted for harness work, saddlery, etc. Speed <500 spi. (In catalog 09/1951)	7x1 or 7x2
7-11		Industrial	For bookbinding. Reversible feed. (In catalog 09/1951)	7x1
7-13		Industrial	For stitching pamphlets (approx. 3/8" thick). Stitch length 1/4" to 1". Drop feed; vibrating presser; speed 100; SDA.	7x1
7-14		Industrial	For harness and other work in leather not more than 5/8`" thick. Makes "set" stitch - 1/8" standard - others were available. Upper feed, foot lifter and SDA.	7x2
7-15		Industrial	Same as 7-13 but with belt shifter for flat belt.
7-16		Industrial	For strainers made of camel hair for cotton seed oil. Stitch length 1/8” to 1/2", No. 14 needle and heavy thread. Drop feed. Two speed balance wheel for foot power stand. Speed 250.	7x15
7-17			As 7-10 but with SDA. Speed 250.	7x15
7-18		Industrial
7-19		Industrial	(Similar to 7-14). Upper feed. Bed plate cut away close to needle. 2-speed balance wheel. For horse brushes.	7x2
7-20		Industrial	(Similar to 7-19). Upper feed. Bed plate cut away close to needle. For horse brushes.	7x2
7-21		Industrial	(Similar to 7-19). Upper feed. Bed plate cut away close to needle. Belt shifter and automatic clutch. For horse brushes.	7x2
7-22		Industrial	Two cylinder shuttles. Gauge not less than 3/4". Adjustable presser. Belt shifter or SDA	7x1 or 7x2
7-24		Industrial	Attachments for circular stitching. For (lighter) buff wheels <3/8" thick.	7x1
7-25		Industrial	One Needle. Drop feed, alternating pressers, cylinder shuttle No 8774 (4" diameter). 15 7/8" to right of needle; stitch length 1/8" to 1/2". For stitching tents, tarpaulins, sails and other heavy work. Leather up to 3/8" thickness. Also for canvas and heavy materials.	7x1 (fabrics), 7x2 (leather)
7-26		Industrial	Two cylinder shuttles. Adjustable presser; narrowest gauge 1".	7x1 or 7x2
7-27		Industrial	2 needles/2 shuttles; gauges 3/4", 7/8" and 1". Upper and lower feed, independently adjustable. 2 to 8 c.p.a. Max 500 s.p.m. For sewing sails, tents, tarpaulins, canvas bags and other work in canvas or heavy fabrics. Also leather & rubber.	7x1 (fabrics), 7x2 (leather)
7-28		Industrial	2 needles/2 box shuttles. For narrow gauges (standard = 1/4", 1/2", 9/16" and 5/8"); stationary or vibrating or presser foot. 2 to 8 c.p.a. Max 500. For sewing sails, tents, tarpaulins, canvas bags and other work in canvas or heavy fabrics. Also leather & rubber.	7x1 (fabrics), 7x2 (leather)
7-29		Industrial	Drop feed; cylinder shuttle. Hinged presser foot. For sails, tarpaulins and other heavy work.	7x1 or 7x2
7-30		Industrial	'Set' stitch. Independent upper and lower feeds, foot lifter and S.D.A.	7x2
7-31		Industrial	Alternating pressers, one needle. 4" high point long beak shuttle; drop feed on one or both sides of needle. Stitch length 1/8" - 1/2"; Presser foot clearance 9/16". Speed 550 spm With SDA. For heavy work in canvas; sail work; wagon covers etc.	7x1 (fabrics), 7x2 (leather)
7-32		Industrial	For stitching buff wheels not more than 3/8" thick and 18" diameter. Makes circular rows 5/16" to 1/2" apart (as ordered). Drop feed, alternating pressers and belt shifter. Speed 300.	7x2
7-33		Industrial	As 7-31, but without driving attachment. One needle. For mechanical or foot power. (09/1951)	7x1 (fabrics), 7x2 (leather)
7-34		Industrial	One needle, long beak shuttle; 15 7/8 inches at the right of the needle. Alternating pressers (vibrating and lifting pressers) with lift of 5/8"; Stitch length 3/32" to 9/16". Oil cup. Underdriver or Foot Power. Speed 650 spm For awnings, mail bags, rugs, canvas covers, horse collars, sails, tents and other leather or canvas items.	7x1 (fabrics), 7x2 (leather)
7-35		Industrial	For harness and other work in leather not more than 5/8" thick. drop feed, presser feed points for stitch 3/32" to 1/4" long. Speed 400.	7x2
7-36		Industrial	Cylinder shuttle; drop feed; hinged presser foot and S.D.A. Speed. 400. For sails, awnings, tents, wagon covers and other heavy work.	7x1 or 7x2
7-37		Industrial
7-38		Industrial	2 needles/2 shuttles. As 7-27 but with S.D.A. For sewing sails, tents, tarpaulins, canvas bags and other work in canvas or heavy fabrics; also leather & rubber.	7x1 (fabrics), 7x2 (leather)
7-39		Industrial	2 needles/2 shuttles. 7-39. Same as 7-28 but with SDA. For sewing sails, tents, tarpaulins, canvas bags and other work in canvas or heavy fabrics. Also leather & rubber.	7x1 (fabrics), 7x2 (leather)
7-40		Industrial	For stitching buff wheels not more than 7/16" thick. Attachment for making spiral rows of stitching.	7x1
7-41		Industrial	Drop feed; alternating pressers and belt shifter. One needle; belt shifter for flat belt. Similar to 7-31	7x1 (fabrics), 7x2 (leather)
7-42			For stitching tents, wagon covers, tarpaulins and general work in canvas. Two needles; two shuttles. 3" diameter cylinder shuttle. Gauges 3/4" to 1". Alternating pressers. Stitches 2 to 8 per inch.
7-44		Industrial	2 needles/2 shuttles. Standard gauge = 3/4"; alternating pressers with Singer Driving Attachment.  2 to 6 stitches per inch. Max 600 R.P.M. For sewing sails, tents, tarpaulins, canvas bags and other work in canvas or heavy fabrics.	7x1 (fabrics)
7-45	(Obsolete by 1955)	Industrial
7-46		Industrial	For bookbinding. Same as 7-11 except fitted with two speed balance wheel, for underdriver. Speed 100 depending on materials used, etc.
7-47	(Obsolete by 1955)	Industrial
7-48	(Obsolete by 1955)	Industrial
7-49	(Obsolete by 1955)	Industrial
7-50		Industrial	2 needles/2 shuttles; standard gauge 1". Adjustable vibrating presser or stationary foot. 2 to 8 c.p.a. Speed 500 SPM. For sewing sails, tents, tarpaulins, canvas bags and other work in canvas or heavy fabrics. Also leather & rubber.	7x1 (fabrics), 7x2 (leather)
7-51		Industrial	Same as 7-50 but with Singer Driving attachment.	7x1 (fabrics), 7x2 (leather)
7-52		Industrial
7-54		Industrial	2 needles/2 shuttles. needles; gauges from 1" to 1 1/2". Independently adjustable upper and under feeds; with Singer Driving attachment. 2 to 8 c.p.a. Max speed 500 R. P.M. For sewing sails, tents, tarpaulins, canvas bags and other work in canvas or heavy fabrics.	7x1 (fabrics), cat £5240
7-55		Industrial
7-56		Industrial	For heavy work in canvas. High point cylinder shuttle. Alternating pressers; SDA; pulley feed. Stitch length: 2 to 8 to the inch. Speed <550.
7-57		Industrial	Same as 7-60 but with puller feed and S.D.A. For sewing sails, tents, tarpaulins, canvas bags and other work in canvas or heavy fabrics. Also leather & rubber.	7x1 5211
7-58		Industrial	Two needles; two shuttles; stitch lengths 2 to 8 to the inch; clearance under presser foot 9/16". Independent upper and lower feeds. Speed<500. For general work in canvas.
7-61		Industrial	Two needles; two shuttles (gauges 1 to 1 1/2"); stitch lengths 2 to 8 to the inch; clearance under presser foot 1/2". Independent upper and lower feeds. Speed<500. For general work in canvas.