[Music] hello friends i am sushant raghwan welcome to technical and quality session for understanding the technical requirements and quality standards in clothing industry making a sustainable garment i have good practical experience in the apparel manufacturing sector my skills are cad pattern making sample development technical requirements and measuring quality performance today's session is about sewing mission field system in garment manufacturing industry for more sessions like this do like and subscribe to my channel now let's begin the presentation sewing machine field system in achieving the objectives of good appearance and performance in seams correct and even stitch length is essential along with fabric joints which are either smooth and unobstructive or evenly eased or gathered according to the requirements of fit and style in the construction of seams and the formation of the stitches that hold them together these requirements are achieved by means of the mechanism that feeds the fabrics past the needle this can either be mechanism at the needle point conventionally referred to as sewing machine feed system or some external system of materials control such as is found in certain specialized machines which are part of mechanized workplaces drop feed system the simplest swing machine feed system and still the commonest is known as the drop feed system the three sewing machine parts which together constitute the droplet mechanism are the presser foot the throat plate or needle plate and the feed dog the throat plate is the most passive of the three parts and its function is to provide a smooth flat surface over which the fabric passes as successive stitches are formed it has one or more slots in it which matches the section of the feed dog and it has a hole through which the needle passes as it goes up and down the needle hole should be only about 30 larger than the size of the needle if this hole is too large fabric can be pushed into the hole with each penetration of the needle drop fade system feed dog the purpose of the feed dog is to move the fabric along by a predetermined amount between successive stitches the amount of fabric movement and thus the switch length is controlled by means of a stitch length regulator the feed dog consists of a toothed surface which races through the openings in the truth plate engages the under surface of the fabric moves that fabric along towards the back of the mission and drops away again below the throat plate before commencing the whole cycle again as the feed dog drops below the throat plate this plate supports the fabric so that it loses contact with the feed dog and is not carried back with it the motion of the needle in an up and down direction must be accurately synchronized with the electrical motion of the feed dog so that the movement of the fabric only takes place when the needle is out of the fabric the feed dock can vary in the number and position of the sections comparison it and in the nature of its toothed surface it is natural in lockset machine to have feed dogs situated both in the right hand to the left of the needle hole to ensure that the fabric is fed in a straight line drop feed system in an overhead machine the feed dog is usually mainly to the left of the needle drop point because it trims and sews the fabric to the right of the needle and because there is a chaining of finger on the throat plate over which the stitch is formed the teeth on the surface of the feed dog can be different types and sizes but are generally slightly slanted towards the direction of feeding for showing off light to medium weight fabrics a toothpick distance from peak to peak of 1.3 to 1.6 mm is normal with the peak slightly rounded off if damage occurs on fine fabrics on very lightweight fabrics shagging can occur between the teeth and pucker can appear after sowing as a result fine toothed feed dogs with a pitch of only 1 to 1.25 mm can be used to prevent this drop field system the presser foot is required to hold the fabric down firmly against the throat plate thus preventing the fabric racing and falling with the needle at the same time it holds the fabric against the teeth of the feed dog as it rises up to transport the fabric it is normally held down by spring pressure in order to give slightly bullish the fabric flies are being fed pressure feet are available in a great many types both to match the varieties of feed dog which exist and to perform additional functions the simplest type of general purpose pressure foot is spring hint to ride over slight variations in fabric thickness and it has two toes so that pressure is maintained on the fabric against the feed dog on both sides of the drop feed system even the simplest of pressure fit feed dogs and road plates all have to be shaped around whether a particular mission has a single or twin needles and whether it's use a straight stretch or a zigzag they may also have to be shaped so that a folding device can be situated close in front of the needle to control the folding of the fabric right up to the point where it is test additional functions which a pressure fluid can perform if suitably designed are such things as guiding stitching a specific distance from a fabric edge or raised seam portioning a cord and folding a narrow hem drop feed system although this simple droplet system is still very common in clothing manufacturing it suffers from a serious limitation in its ability to produce themes of perfect appearance on all types of material more seams on garments required to be joined smoothly without any pucker showing in any of the materials assuming that two or more thickness of fabric are sewn together regardless of whether they are separate fabrics or folded section of the same fabric the problem arises that the friction between the bottom ply and the feed dog is normally greater than that between intervening plies the tendency is for the lower ply to be taken satisfactorily through the machine by the feed dog and the top line to be by the pressure foot the problem is variously known as interplay shift differential feeding pucker or just feeding pucker in swimming ahem twisting may occur between the layers of material and the problem known as roping will arise differential bottom feed differential bottom fade is the name given to a feed dog which consists of two sections one behind the other the movement of each section is similar to the moment of the whole feed dog in the drop feed system but the stroke or moment of each part can be adjusted separately or differently figure 1 bottom field set to stretch lower ply figure 2 bottom feed working fullness into lower ply in the situation where differential feeding pucker is a problem correct adjustment of this feed system to create slight stretch on the bottom ply will overcome the tendency of the feed dog to take in that ply while the presser foot retards the top line differential fade is available on chain stretch overage and safety stretch machines as well as on lock shift machines when overhead joining soft knitted underwear fabrics where there is a high level of friction between the plies there is a tendency for the presser foot to stretch both plies and thus to show in some stretch along the seam a differential feed system can be said to prevent this as in this case the friction between the plies is sufficient for the motion of the split feed dog to be transmitted to both of them variable top fade with drop feed when a variable top fade is combined with a drop fade there is the opportunity to speed up the movement of the top fly to achieve shift free swing or by further adjustment of the top feed mechanism to introduce a deliberate amount of ease or gather to the top fly figure 1 to finish e1 figure 2 to work fullness into top fly adjustable top feed systems can take more than one form but all provide control on the top fabric fly in a way which allows for adjustment so that the fabric flies will either be fed through exactly together or if required the top fly will be gathered onto the bottom fly the general arrangement of such top field system is that the pressure foot is in two section one holding the fabric in position while the needle forms the stitch and the other having teeth on the lower side and moving or walking in such a way that the top fly is taken along positively while the needle is out of the material variable top fade with differential bottom feed when a variable top fade is combined with a differential bottom feed all possibilities are available for achieving ease or gather in either the top or the bottom fly and for achieving shift free swing figure 1 to work fullness into top fly figure 2 to work fullness into bottom fly such a combination of feeding systems with both the top feed and the bottom feed being independently variable is the most logical to apply to most seeming situations since it can be adjusted to feed each fly exactly as required in relation to the other missions are available on which the required amounts of fullness can be pre-programmed and altered by the action of a finger knee or foot switch as needed along the length of the seam overaced machines are also available with differential bottom feed and wearable top fade with the top fade able to act in front of or behind the needle in order to give the best effect on a particular fabric compound fade needle fit is the name given to the field system in which the needle itself moves forwards and backwards used on its own it tends to produce elongated needle holes in the fabric and to avoid this it is normally combined with a drop fade and given the name component fade the needle enters the fabric moves back with it as it is moved along by the feed dog to form one stitch and then raises up and forward again to begin the next stitch thus the needle is in the fabric while fading is taking place and the plies of fabric are held together it is particularly useful in bulky swing situations such as when quilting through fabric and wedding with this field system the needle and feet dog movements are synchronized to ensure that the flies retain their correct alignment during swing unison fade unison fade is a further combination of feeding mechanisms which provides needle fade in addition to positive top and bottom feeding of the two part presser foot the center part moves with the needle its applications are limited since one little feed is included in a system which also has variable top and bottom feeding it removes any opportunities for adjusting the amount of fading in the top and bottom plies by means of the separate upper and under feeds this system is also known as a working foot system because the presser foot has two independently different sections these two sections alternatively advance and hold the price in alignment an important requirement when showing bulky seams in heavyweight materials puller feed a puller feed is a way of providing positive control of all the plies of fabric as they leave another feeding mechanism such as a drop feed two rollers exert a pulling motion on the fabric immediately behind the presser foot or a short distance behind it both rollers may be driven or the top roller only may be driven while the lower one idles pooler feed is particularly useful in multi-needle stitching of parts such as waistbands and it may be set slightly faster than the main mission drop feed to overcome any tendency for the seam to twist [Music] thank you for watching for more sessions like this do like and subscribe to my channel please comment your valuable thoughts and don't forget to press the bell icon to get notified when i post a new presentation bye have a good day