Adjusting the tension of the overlock threads
To get a high.quality overpass, it is necessary to master the adjustment of the tension of the threads. Modern overlocks facilitate this task thanks to the regulators taken on the front panel. Under each disk is a scheme that helps to understand that the behavior of which thread can be adjusted with this switch. However, it will take some time to learn how to confidently and the first time regulate the threads when working with different fabrics.
If you want to see how an overlapping seam is formed in your car, season multi.colored threads. You will see the components of the stitch and in the future immediately orient yourself in which thread needs adjustment. The larger the number on the regulator, the stronger the tension.
To minimize the volume of settings, select the optimal length and width of the stitch. Values should approach most materials with which you work. You just have to adjust the tension under the thickness of the fabric. When changing the length and width of the stitch, you will need to perform an additional tension tuning.
The appearance of a flat seam on factory products
In the upper photo, you saw a 3-needle version of a flat seam, and from the wrong side. But this option is rare, most often a 2 needle flat stitch is used, which you can see on any T-shirt (sleeve, bottom extension). Most likely, this is due to the economy of the threads. So, for example, the processing of one T-shirt on the wagon “eats” at least 3 spaces of threads (200 meters each). That is why only conical large bobbins are used for planning machines.
How to sew knitwear with a double needle
Sewing knitwear with a double needle will require a special approach. It is best to adhere to the following recommendations:
- In the settings of the machine, select a straight line.
- Select the length of the stitch depending on the elasticity of knitwear.
- Slightly reduce thread tension to make the seam more flat.
- It makes sense to set different settings and conduct tests on unnecessary fabric elements. Then the most suitable option is selected.
- It is not recommended to make a fixture method. In this case, the risk of tangling threads will increase.
- You can prevent stretching with a water-soluble stabilizer tape or simple pushing the material under the foot with any tool.
- An excellent solution would be to use a special walking paw, which provides uniform supply of the upper layer of fabric.
- Tissue tightening can be minimized by reducing the tension of the upper thread or using elastic adhesive material.
- To pass difficult places, it is advisable to use special plates that prevent the passage of stitches.
How to choose a needle?
Universal needles with acute tips that are equipped with sewing machines are not suitable for working with elastic knitted canvases, as they provoke the appearance of small penetrations in the seam. This problem can be avoided using special “knitwear” needles with rounded tips. They do not cut down, but carefully push the fibers of the material, maintaining its integrity.
Large companies producing goods for sewing adhere to a single classification of “knitwear” needles. They are three types:
Jersey is used for 100% cotton or unimportant material with insignificant (up to 10%) m polyester;
Stretch is used to work with cake, kashkorce, ribana, a footer, which includes more than 10% polyester and/or there are fibers of Elastan;
Super Stretch is chosen for well.stretched paintings with a lot of elastan (biflex, linen grid).
When selecting a needle, you need to pay attention to the density of the material. Positions marked with number 90 are suitable for sewing a foot with a horseman, 80-for a footer 2x-nickname, 75-for the culinary surface, mesh, knitted guipure. The more delicate material, the thinner the needles and threads that are used in work should be.
Needles that are marked with the words Overlock, Serger or the abbreviation ELX705 are created specifically for flat spacing machines or overlocks. They have a large length of the rods necessary for the proper formation of a chain stitch, so it is impossible to use them in universal household sewing machines. This ban works only unilaterally. Ordinary “knitwear” needles are suitable for domestic vegetable machines and overlocks.
It is important to remember that even a correctly selected needle cannot serve forever. It is believed that the average time of its production ranges from 4-6 hours of continuous sewing. The regular change of this part in the car helps to reduce the risk of passing the stitches in the line and prevent the appearance of penetrations in the seam.
How to sew knitwear on a household sewing machine
A line laid on knitwear is torn when stretched? The stitches look unevenly, and the layers of the material “go waves” or move relative to each other after sewing on a household sewing machine? We figure out why this is happening, and tell us what to do to avoid the appearance of these problems.
Knitwear. material that has high elasticity. To work with it, they use an external machine and an overlock, which can perform single.line or multinitable chain seams formed due to the interweaving of thread loop. Such a seam is relatively easily blossomed when cutting, but can stretch, and then return to its original position.
Household sewing machine is capable of making only shuttle stitches, which are formed by weaving two threads: the upper needle and lower shuttle. Such seams almost do not bloom, but are torn when stretched. Therefore, sew knitwear with an ordinary line designed to tighten inelastic fabrics is incorrect. For these purposes, special “knitwear” seams should be used, which can withstand light stretching:
A strong enough, elastic seam, which is in most household vehicles with a needle hole with a width of 5. 7 mm. In order for the zigzag connecting line to look neat, the length and width of the seam on knitwear should be reduced to 1.5. 2 mm.
In comparison with a classic zigzag, this option is more durable and elastic, since the seam formation requires more needle punctures. As a rule, intermittent zigzag is used to grind high extensibility knitwear: microfibers, biflex, as well as for sewing rubber bands to linen and swimwear. The length and width of the intermittent zigzag should be adjusted on the sample to achieve the correct balance between the appearance of the seam and its functionality.
The ideal option for laying finishing and fixing seams on the face of the product. On the outside, it looks like two parallel straight lines, and from the wrong side. as a zigzag, which gives the seam the necessary (but smaller than that of a full zigzag) elasticity, and fastens the stitches among themselves.
To sew knitwear, only those double needles should be selected that have the appropriate marking and are suitable for working with elastic fabrics. The standard zigzag width in most cars is 5 mm, therefore, for them you can use double needles with a width of 2.5 to 4 mm.
Contour knitted (elastic) stitch
Outwardly looks like a straight line, the stitches of which are located with a small, barely noticeable bevel. Such a seam works well when grinding vertical lines. When stitching horizontal areas, the material can be deformed. In order to minimize additional stretching, you need to allow the machine to promote the canvas itself, controlling only the direction of movement, but not the speed of the knitwear supply.
Most overlocks and extinguishing machines have a function of differential supply of fabric, thanks to which the material can slightly stretch or compressed depending on the tasks of the tasks. It simplifies the process of promoting knitwear under the paw and reduces the risk of landing on stuck layers relative to each other.
In household sewing machines, a gear rake is responsible for the supply of fabric, which promotes the fabric towards the needle. When two or more layers of the material, the bottom moves faster than the upper ones, as a result of which a small but tangible landing occurs on knitwear, the needle passes the stitches and breaks the thread.
The solution of this problem is the use of special legs. They do not just slide along the upper layer of the material, but pushing it synchronously with a gear rack. There are different options on sale that are suitable for most modern sewing machines. The upper conveyor is considered the best, the use of which makes the supply of fabric uniform and allows you to sew knitted materials in a straight line without preliminary tags. An alternative to such a device is a walking paw equipped with a silicone pad that reduces the risk of skipping stitches and simplifies the process of promoting the material.
Only special needles with a rounded tip are suitable for sewing knitwear, which does not break through the fibers of the material, but pushes them to the sides, maintaining the integrity of the canvas.
We will analyze the classification of such needles using the example of the products of the German company Schmetz:
Jersey. needles for 100% cotton or unimportant material with insignificant (up to 10%) m polyester;
Stretch. for working with cake, kashkorce, ribana, footer, which includes more than 10% polyester and/or there are fibers of Elastan;
Super Stretch. for well.stretched paintings with a lot of elastan (biflex, linen grid).
BERNINA #2A overlock foot.
Stretch Twin Needle. double needles for working with elastic culinary surface, kashkors, ribana, foot.
When buying needles, pay attention not only to the letter marking, but also to the numerical designations indicated on the packaging. Options with number 90 are suitable for sewing dense knitwear or a footer with a hose, 80 for three-ninca stella, two-names and dense biflex. 75. for the culinary surface, microfibers, mesh, knitted guipure and other thin tissues.
Before you start sewing, you should check the quality of the machine line on the sample: configure the appropriate tension of the needle and shuttle threads, weaken the pressure of the pressing foot, adjust the sewing speed (it should be slow, and pressing the pedal. smooth).
Do not use thick, loose cotton threads or threads designed for decorative decoration. The best choice in the case of knitwear is a thin high.quality synthetics that will not deform the fiber of the material.
Before grinding the knitwear, you need to pre.sew the sections or cheap them with pins across the future seam to avoid displacement of the layers of fabric. It is possible to neglect this rule only if you have a special paw. the upper conveyor.
Elimination of common problems
If the mother does not move when hug, then the foot presses the fabric very weakly. When working with too subtle matter, it is necessary that the pressure of the paw is minimal or the fabric will wrinkle.
- Turning the thick material, pressing the foot must be increased.
- The cliff speaks of an incorrect refueling. The threads of the loopers should refuel with special care. In certain types of machines, you can only season with curved tweezers. the process is quite complicated.
- The use of the scheme will correctly insert the thread in the necessary places, the passage of one mount will lead to the uneven seam.
- The cliff may be the result of an incorrectly selected thread. The threads used are also important for working on the overlock, they are indicators of the estimated seams. Different quality and thickness will affect the change in the pattern of the seam. It is better not to use thick or cotton threads. Thin and elastic easily passes through the processed fabric, to the needle, buttonholes. It is recommended to use the same threads on conical bobbins.
- Bowing is possible due to an incorrectly wound thread to the coil. It is necessary to check the direction of the thread of the thread.
The passage of the stitches may be a consequence of the fact that:
- The needle is bent or non.ostra. The dumb needle is determined by conducting the nail of the thumb along the tip of the needle around the circle. If the needle is bent, the nail will feel it. The same can be done using a magnifier. If a defect is detected, you should not straighten the needle. this is unacceptable for the exact tuning of the overlock. It is important to study which needle is in the typewriter and use only those categories and brands that are recommended by the manufacturer by the factory. The needle is incorrectly installed;
- The needle cannot be applied according to the recommendations of the manufacturer’s factory, incorrect;
- weak pressing of fabric with a paw;
- Passing one of the thread mounts.
Stitch size and cut
To make the seam high.quality, it is advisable to determine the width and length of the stitch. The presence of a universal regime provides standard work on the overlock on most fabrics. To perform small seams, it is not necessary to configure the machine.
The largest indicators are required in cases where a larger volume of fabric must be accommodated inside the stitch. With minimal values, it is quite difficult to work: due to the optimal tension, its periodic breakdown occurs.
Pressure of the clamping paw
When processing thin tissues, it is important except to adjust the thread tension to control the pressure of the crush foot. You can use such a function not on every overpowing machine.
To adjust the clamping paw, a special screw is used on the upper part of the case.
The manufacturer during the initial setting sets the average value that is suitable for most fabrics.
If the pressure is reinforced, then the foot holds the material in place and the seam will be tightened. In this case, you need to loosen the pressure on the fabric, turning the screw using a screwdriver counterclockwise. Turning. On the contrary, the pressure will increase. This adjustment also needs to be tested in practice to understand how it works.
The renovability of the knitted fabric is characterized by the appearance of small pederates in the machine stitch area. It may be insignificant and almost never manifest itself, but can become a serious problem that will lead to the fact that the thing will literally disperse at the seams. We will deal with the causes of the stripping, we will understand how to reduce the risk of a defect and make a checklist to create a high-quality line on knitwear.
Knitwear extension is a consequence of several reasons that can provoke its appearance to one degree or another. Among them:
incorrect tension of threads in sewing technology;
incorrectly configured pressure of the pressing paw on the material;
the composition of knitwear and the quality of its production;
We will deal with each of these reasons in more detail.
How to choose needles and threads for knitwear
Incorrectly selected needle is one of the main reasons for the extension. To avoid the problem, you should use special needles designed to tighten knitted materials.
European manufacturers adhere to a unified classification of “knitwear” needles:
Jersey. Suitable for 100% cotton or unimportant material with a small (up to 10%) m polyester;
Stretch. Used for the culinary surface, kashkors, ribans, footers, which contains more than 10% polyester or there are fibers of elastan;
Superstretch. Designed for well.stretched paintings with a large amount of elastan (biflex, linen mesh).
The needle number also matters. Make sure that it corresponds to the density of the material. The smaller the needle number, the more delicate the puncture will turn out, and vice versa. As a rule, for a dense foot, it is advised to choose needles marked with 80–90 numbers, for the culinary surface. 75, for thin viscose and mesh paintings. 65. What else to pay attention to when choosing a needle for knitwear, read in this article.
Another factor that needs to be excluded in order to maintain the integrity of the canvas is incorrectly selected threads. Completely synthetic options affect the extension more than reinforced threads with cotton or syllabic (viscose) braid. The thicker the threads, the higher the likelihood that the material will be tightened when sewing, and the cotton fibers of knitwear is to deform from friction.
Incorrect tension of compensation springs of a machine or overlock is a common cause of abruptness in the seam. Configure this parameter in accordance with the recommendations specified in the operating manual for your sewing equipment. Make a test line on a sample folded in two layers, and check it for quality, pulling the material in different directions. If the line is unnecessarily pulled out, weaken the tension of compensation springs and make sure the correctness of new settings on the sample.
Insufficient pressure of the pressing paw on the material leads to the fact that it moves unevenly, which is why not only the quality of the line, but also the integrity of the fibers of the canvas suffers. Excessive pressure, on the contrary, provokes a delay in the promotion of the material, stretching knitwear in the seam area, which also negatively affects the integrity of the fibers when interacting with a machine needle and thread. To understand that there are problems with tension, you need to observe the smoothness of tissue advancement during sewing and adjust this parameter.
Knitwear development is an important point that also affects the appearance of violence. The “singing” or “compact singing” canvases are significantly less than the “card” and openend, due to better raw materials from which they are produced.
Drama is more characteristic of knitwear with a large amount of cotton in the composition. The fact is that fibers made from natural plant materials are more fragile in structure in comparison with long and strong synthetic threads. This does not mean that materials with mixed compounds are not susceptible to penetration, holes in the seam can also appear on them, but in a quantitative ratio there will be less than 100% claps. information about the quality of knitted paintings and the difference between cotton and synthetic threads can be found in this article.
In addition, the seams in the seam can appear on low.quality canvases that are excessively overdried during color fixing after painting. Violation of drying technology leads to deformation of cotton fibers, and they are more actively torn in the places of punctures of the machine needle. You can determine the overdled knitwear tactilely and visually. as a rule, it is more tough to the touch and hesitates even from a slight compression.
A checklist for creating a line without rubbing
Swate only with high.quality European needles, Jersey / Stretch / Super Stretch, correctly selecting numbers for each specific material. Change the needles after one or two stitched products for new.
Use threads whose numbers correspond to the density of the canvas. The thinner the material, the thinner the thread should be. You can refuel special soft textured threads into the overlock loopers.
Adjust the level of pressure of the foot, taking into account the density and extensibility of the fabric. Focus on the quality of machine line on the sample. During sewing, do not pull the details of the product, let the toothed conveyor drive the fabric on your own.
Set the optimal length of the stitch (3-3.5 mm) to avoid unnecessary punctures of the material.
Set up the correct tension on the sewing machine and overlock with colored threads. Be sure to check the resulting lines for the break, pulling the sample in different directions to identify hidden plunging.
Drive the details of the products in accordance with the shared thread (along the columns of knitting or along the edge) so that the tension of the material is uniform.
If the canvas seems dry and hard to the touch, you can carefully moisten the seam area from the spray gun. This technique will moisturize knitwear fibers, make them softer and elastic. Pay attention: when using water, the edge of the overwhelming parts can be excessively stretched. This can be fixed at the WTO stage and by adjusting the overlock differential.
Description of problems and instructions to eliminate them
The application of the following recommendations and instructions will solve problems with the skipping of stitches when working on the overlock.
Changing the thickness of the fabric
A common problem is when an overlock passes the stitches when switching to several layers of fabric. As soon as the total thickness of the fabric has increased, the skills of the stitch appear. In this case, the tension of the needle thread is reduced when the tissue is switched to several layers.
When the site is passed, it is necessary to return the tension of the thread to the previous position. You need to work slowly so as not to miss the right moment.
This method is only suitable for adjusting the working overlocks. If the line gives omissions on one layer of fabric, then the reason is not in the tension of the thread.
Dumb or bent needle
Even a slight curvature will lead to a passage of stitches. The reason for the curvature: the buttonhole and the nose of the shuttle of the overlock is beaten into the needle, and under this effect it is deformed. When working on the overlock, dull knocks appear when tissue tissue.
It is very difficult to visually determine the curvature, so you can check the bent in the way shown in the picture.
The second way to determine bent: on a dark surface, quickly scroll through the needle. If the tip does not change the position and remains in one place, then it is even.
Checking the needle for bent in such ways, the reason for passing the stitch is revealed.
Dumb needle will cause the seam unevenness and the passage of the stitches. Sharp effect affects the gap between the button loop, obtaining the correct estimated seam without gaps. The tip is checked in two ways.
Through the magnifying glass, consider the tip. If the tip is rounded on the bar, then the needle is stupid.
run the thumb fingernail along the tip from the flask to the tip. If the tip is deformed at the end of the needle, then the nail will find a blunt.
You can not use needles with defects or rust, since their use leads to negative consequences:
Low.quality or incorrectly selected needle
Each overlock is attached to operating instructions that indicate the type, brand and thickness of the needles recommended for this model. Dimensions depend on the thickness of the fabric and threads.
Unlike sewing machines, overlock needles have significant differences. The shape, the diameter of the flask can be thinner or thicker, and the length is shorter or longer. Such differences affect some overlock settings, failures are possible, including the skills of the stitch.
High.quality needles are made of high.strength steel that do not bend, but break when trying to bend it. When choosing materials, there should be a “golden mean”. this is the correspondence of a needle, thread and fabric. Low.quality needle on complex, stronger fabrics forms the passage of the stitch. In this case, it is worth changing it and the passes will disappear.
Error when installing a needle
Incorrect installation will lead to damage to the needle. If when installing a new line is not formed, or formed, but with a large number of passes, then it is installed incorrectly.
- prepare a needle recommended by the instruction manual;
- The sharpening of the flask should be located in the direction of “from yourself”, and a long groove, where the thread is refuel. “from itself”;
- The needle should reach the stops and clearly stand up.
When replacing two needles, the installation is carried out in the same way, but the right needle will be several millimeters above the left.
After working with the fabric, especially with knitwear, the overlock is strongly contaminated because the knife cuts off the remains, and they fall into the inside of the overlock.
The threads are wrong or poorly tilted
Special threads are produced for overlocks, so any, including for sewing machines, can not be used. Material, thickness and quality affect the tension of the thread.
Low.quality or incorrectly selected threads will lead to a passage of stitches or in general to their absence.
The display of the needleman
In the process of work, the needle can fall into the needle plate, and not into the hole intended for it.
Since the speed is high during operation, when the material is supplied, a sharp blow occurs: the needle rests, and the overlock mechanism still crushes. Thus, an needler shift occurs.
Когда игловодитель оверлока смещается, игла становится выше и петлитель не попадает в отверстие, поэтому стежки не получатся.
If the displacement is small, then the sting of the buttonhole partially captures the thread, so the passes of the stitches are formed.
In that case, it is important to get the position of the needlerer in which the buttonhole flies into the loop with his sting.
NECCHI Piping Foot For Overlock Machine
The elimination of such a problem requires the professionalism and knowledge of the internal structure of the overlock, so it is better to contact the master.
Problems with a paw
From a long.term mark, the crush foot can begin to press the fabric poorly. When the fabric is poorly pressed, the skills of the stitches are obtained. To eliminate this problem, it is recommended to adjust the foot pressure spring.
The appearance of backlash
If the passes began to form gradually, and over time they became more and more, then this is a sign of backlash. That is, a gap between the mechanisms appeared, and the larger the backlash, the more often the passes of the stitches on the overlock become.
The approach to eliminating the problem is this: to check all the connections that are responsible for the movement and transmission of rotating moments, and tightly tighten.
The shift of the cang clamp
In some models of overlocks, especially Soviet or Russian.made, the needle retention is a zangic clamp. If you pour a zanging clamp or give it, then it crushes, and it will not work to put a new needle to the end. In this case, the nut turns out, and the petal petals are divorced. After that, the needle reaches the stop and clearly gets up.