Why the sewing machine makes gaps on a line
Like any mechanism, the sewing machine is subject to various breakdowns, however, for devices of this type, there are typical and most often encountered cases. For example, why a sewing machine passes the stitches while maintaining a line? To answer this question, you need to look inside the device and find out the features of its functioning.
The so.Called sewing line appears as a result of the interaction of a needle and a special shuttle device. The nasal part of the shuttle comes close to the needle and lifts the loop from it. After that, the part worsens the upper thread and creates a shuttle stitch.
If the mechanisms work harmoniously, and the setting of the sewing machine is not broken, the gaps in the line during sewing are excluded. However, if the operating rules are not observed or, as a result of wear of parts, malfunctions may occur in the process. Consider examples of situations that lead to the formation of passes in the stitches, and ways to eliminate them.
Classic overlock lines
Let us consider in detail the common lines that can be made on an overhead machine.
2 thread seam is performed mainly on very thin fabrics, where a minimum of thread is needed.
It is easier to work with very “moody” fabrics by such a seam. Especially if massive details are injected into them: lightning, brooches, large buttons. 5. The thread line makes the seam more durable. It can be seen on summer female blouses from crepe densit, chiffon, organza and other thin naughty tissues.
The principle of regulation does not depend on whether Taiwanese, Japanese or Chinese you have an overlock, since they are taken on the outer side of the car body tension regulators. As a rule, there are 4 of them, according to the number of threads involved in the grinding process. All regulators have a scale of tension degree from 0 to 9.
For each type of fabric, before starting work, you need to configure an overlock.
The values of the regulators are set depending on the thickness of the fabric and the type of thread used. In most cases, the mark can be performed with the set tension value under the number “4”.
But do not immediately start processing the product itself. Pre.Check the quality of the shaft of the seam on the fabric flap and, if the process is normal, you can start work.
The degree of tension of the thread is regulated as follows:
- From 2 to 3. Weak tension;
- From 3 to 5. The average tension force;
- From 5 to 7. Strong tension.
An important condition for the high.Quality embrace of the material is the thickness of the thread, and it is important that all 4 threads are of the same type and thickness. Another condition for obtaining a flat traffic line will be the correct selection of the number of the needle thickness corresponding to the density of the processed fabric. Typically, for each overlock in the operating instructions, the manufacturer indicates the brand of needles and their recommended numbers.
If the needle is selected inappropriate size and thickness, this can lead to the malfunction of the process, and in some cases even to breakdown of the machine.
Reasons why the sewing machine misses the stitches
A stitch is the result of the interaction of a needle and a shuttle. If the interaction is disturbed, then the skills of the stitches occur. What can violate this interaction? The most common cause is too much the gap between the tip of the needle in the extreme lower position and the nose of the shuttle. This gap should be 0.3 mm, and better even less. If for some reason (we will consider them below) the gap has increased, then the shuttle mechanism is not able to pick up the thread and there is a pass. This is the main reason, although not the only. The quality of the line also depends on the adjustment of the tension of the upper and lower thread, the quality of the needle and thread, the correspondence of their size and the thickness of the fabric. Cleaning all moving nodes and their lubrication is also not the last factor in uninterrupted sewing.
Incorrect settings of the sewing machine can lead to the fact that the sewing machine passes the stitches. Over time, especially after frequent operation, the needle of the sewing machine can change its position or completely bend. This can affect not only the evenness of the line, but also for all the work as a whole. To eliminate the malfunction, take out the bobbin cap and carefully inspect it.
- Explore the condition of the needle: if it deviated to the side, the tip turned off or has external damage, replace it with a new.
- When installing a new part, make sure that it is inserted all the way. Also check the tightness of a special screw for fixation. If he gets sick, use a screwdriver entering the kit and tighten it.
Adjustment of such an exact mechanism requires special attention and scrupulousness. If you do not have enough patience, or there were no necessary tools at hand, contact a competent specialist.
The overlock is packed in a box of dense cardboard, on which all the necessary information is applied about the machine itself and the manufacturer.
Inside the box, the overlock is placed in an additional foam box that protects it from damage during transportation.
Serger Stitching Troubleshooting
Together with the overlock in the box there are instructions in Russian and a warranty ticket.
Anatomy of overlock lines
The 4-minute overlock seam is formed by two needle threads and two threads. Although there is no need to use multi.Colored threads in your overlock to see the components of the stitch, you could still use this technique, and would be considered useful. The drawing on the left shows the upper and lower sides of the fabric with an overlapping stitch. On the upper part (which is turned upward during the line), you will see two rows of stitches forming parallel lines in relation to the edge of the fabric. They are made by needles. Loops of threads that run more or less horizontally are formed by the upper loop. On the bottom of the fabric passes the thread of the lower loop, which is attached by almost invisible stitches from the needles. That which resembles a series of direct stitching on the inner edge of the line. In fact, an example of the formation of secret (invisible) ends of the loops.
Beginner’s Guide to Serging (Ep 4): Overlock Stitch Intro to Tension
The installations of length and width affect overhead lines. Select these values and then adjust the tension of the threads so that they satisfy them. For the main overpass and finishing lines, I choose a universal combination of length and width, which will work for most fabrics with minimal adjustments.
As in the usual sewing machine, the length of the stitch 2.5. 3 mm is well suited for most fabrics. Shorter or longer stitches can lead to wrinkling or tightening.
Installed width of the stitch on the overlock. This is actually the width of the cut line: the value set in the machine regulates the distance from the cutting knife to the needles and, in turn, the amount of fabric that remains inside the overlapping stitch. The largest cut width leaves most of the fabric inside the stitch. I rarely use a narrow cut width, t.To. The installation of the tension required for a balanced stitch is often so high that the problem of a break in the threads arises. A narrow cut width can be redeemed (but not always necessary) for role.Playing and other specific lines.
Overlock.51 cl. (industrial three.Native)
We give a brief description of the most common malfunctions and ways to eliminate them in the “Overlock”.51 cl. (industrial).
Rice. 172. Left engineer of the vehicle “Overlock”.51 cl. PMZ:
Rice. 173. Right-header loop of the car “Overlock”.51 cl. PMZ:
Right loop (cm. Rice.173) is attached so that it is impossible to move it from the place of fastening: landing with a groove 4. Therefore, its mutual connection is ensured only by bending the buttonhole himself back and forth, providing a gap with a left button of approximately 0.05-0.1 mm.
This is practically done like this: bend the right loop forward; If, when meeting with the left button, he hurts for him, slightly bend his right looper. Here it is necessary to keep in mind the difficulties of configuration in the fact that the mutual connection of the buttonholes on the right side is closely agreed with the mutual component of the left button with a needle. To debug the right side (mutual assurance of the buttonholes among themselves), on the left side the left loop can touch the needle or the right loop can touch the needle. But there is one only correct mutual connection of the needle with both buttonholes and buttonholes among themselves. This is the only option for Inado by adjusting the fist, which is located on the left on the main shaft.
Loosen the stop screw of the column of the motionless knife.
Shift the block to the right by 0.5-0.8 mm.
Moving the foot to the right or to the left adjust the cleanliness of the line. The same can be achieved by displacement to the right or to the left of the finger on the paw. The quality of the line depends on the thickness, tension and quality of the threads.
Rice. 174. Pressure device of the movable knife “Overlock”.51 cl. PMZ:
|1. Mobile bracket;||4. Clamping spring;|
|2. Frame;||5. A screw of displacement of a knife;|
|3. A screw of the radial displacement of the knife in the vertical plane;||6. Movable knife|
In order to change the step of the needle, you need to open access to the back of the overlock and see the mechanism for changing the needle step. Horizontally located connecting rod 3 (cm. Rice. 175) with its big end, planted on an eccentric shaft 2, which is fixed with two screws on the main shaft 1. The small end of the connecting rod is connected by a hinge 7 with the cululis 6. The backstage 6 is fixed with the terminal mount 5 on the shaft of 4 gear racks. To change the needle pitch, weaken the screw 7 and lower it or raise the end of the connecting rod on the backstage and fix it. The rise up. The step will increase, down. Decrease.
Rice. 175. Tough rail step adjustment unit:
|1. Main shaft;||5. Fastening of the backstage;|
|2. Eccentric;||6. Qulisa;|
|3. Connecting rod;||7. Mounting a connecting rod on the backstage|
|4. Shaft with a gear lever;|
If the edge of the fabric is bent inward. Move the finger on the paw to the right, if the mark does not completely cover the edge of the fabric, the finger move to the left.
To change the width of the estimated line, you need to loosen the screw of fastening of the well on which a fixed knife is fixed. When it is displaced, the line will be wider, to the left. The width will decrease.
One of the main conditions for the normal operation of the overlock is the correct tension of the threads. The gaps between the needle and the buttonholes, as well as between the buttonholes at the time of their meeting, is 0.05 mm.
The position of the needle, when it is in the extreme upper position relative to the right loop, which occupies the extreme left position, at a distance of 1 mm above or below the output, or at the same level. The largest percentage of passes in all overlocks is observed in case of violation of this particular parameter. When setting up an overlock, you need to start with the installation of the left button and needle, then the right loop and needle.
The task of the left button is to remove the thread from the needle when it begins to move from the extreme lower position.
The task of the right loop is to remove the thread from the left loop at their meeting. The task of the needle is to remove the thread from the right loop. Adjustment methods: displacement of the needlerer up and down, the shift of the buttonholes in the places of their fastening or their hem.
Overlock care tips
Like any other technique, Overlock needs periodic care. Machine maintenance consists of the following manipulations.
- After the work is completed, you need to remove particles of threads, fabrics and dust from available work surfaces using a brush.
- After complete cleaning, moving overlock mechanisms must be periodically lubricated with special oil.
- In case of suspicion or detection of serious malfunctions for repair, you should contact a specialized service center.
Setting up a sewing machine requires concentrated attention and complete returns of the process. Get ready for the fact that you will spend the whole hour on the fit of all the settings necessary for the work. When carrying out the procedure, you can not rush if you are not sure that you can handle it yourself, it is better to contact the master.