Do-it-yourself class 51 overlock repair

Overlock class 51 - this is the most widespread industrial overlock of the "Soviet" period. It was impossible to buy it in those days, but such overlocks were in every atelier, sewing workshop and even a sewing factory. Despite the fact that this overlock is from the "last" century, nevertheless, it is still often used at home, in small ateliers for sewing and repairing clothes.
Morally, this sewing technique has long been outdated and many modern fabrics are simply impossible to overcast with high quality. However, it is sometimes justified to use a 51 class overlock, since it does a good job with such fabrics as denim, drape and even thin tarpaulin.

Affordable price is another advantage of this overlock. The cost of a used overlock is an order of magnitude lower than the prices of modern overlock models, and even more so for household carpet locks. Especially, this difference is noticeable in comparison with the prices for industrial overlocks. For 3-4 thousand rubles it is quite possible to buy such a used overlock, moreover, of a rather “decent” look.
The 51 class overlock has another advantage - reliability. This is a fairly reliable overlock, parts break extremely rarely, only sometimes it becomes necessary to perform minor repairs and adjust the overlock.

All instructions for the 51 class overlock have long been lost, or maybe they were not there at all. There is practically no literature written in an understandable language, the services of a master sometimes cost more than the overlock itself, but you need to set up the overlock. For such a case, we offer you small recommendations of our own on how to set it up. overlock 51 class.

The 51st class has a unique feature - it can work using only two strings. Perhaps such a “saving” is no longer relevant today, but you should know that if you put a spreader instead of one of the loopers, the overlock will work “on two threads”. One is threaded into the needle, the other into the looper.

Maximum rotational speed of the main shaft - 3500 rpm;
Stitch length - 1.5. 4 mm;
Overedging width - 3-6 mm;
The maximum thickness of processed fabrics is 2.5 mm.

The 51 class overlocker is distinguished by the presence of a differential fabric motor (slats). A 51-A class machine has a simple rail. It can be more easily explained as follows. The 51 grade overlock rail can stretch the edge of the fabric to be overcast, making the seam elastic after overcasting. This is very important for finishing knitted fabrics and is indispensable for sewing sportswear, T-shirts, etc. Therefore, he can efficiently overcast not only suit and coat fabrics, but also knitted, linen fabrics with knitted weave threads.
Outwardly, both overlocks are exactly the same, but the presence of a differential rail greatly increases the capabilities of one of them.

Both machines use short needles with a thickened bulb. The marking of the needles indicated on the package should look like this: needle type - 0029, needle thickness - No. 60, 65, 75, 90, 100.

To set up an overlock yourself, one instruction is not enough, experience is definitely required. Correct interaction of the loopers and the needle with each other takes place while observing many parameters. It is quite difficult for an inexperienced “master” to expose them exactly. Therefore, if you do not know how to do this, it is better not to try. Moreover, most of the defects of poor stitching have other reasons, such as incorrect thread tension, dull or bent needles, poor quality threads, etc.

In this manual for the class 51 overlock, the basic settings for the interaction of loopers and needles are given, which can only serve as a guideline for a “rough” setting. "Fine" tuning of the overlock is made taking into account many factors that have individual characteristics for each overlock. The general principle of setting the overlock is as follows: all loopers and needles “meeting” must have minimum clearances. The looper must “confidently” enter the loop formed above the eye of the needle, the needle must firmly enter the loop formed by the looper.

The main reference point when setting up a class 51 overlock is the left looper (lower) L. When lowering the needle to the lowest position, it should take the leftmost position. The point of the looper at this moment should be at a distance of 4.5 mm from the needle.
When the needle is raised 2.5-3 mm, a loop is formed just above the eye of the needle. The nose of the left looper, moving to the right towards the needle, extending 1.5 times. 2 mm above the eye of the needle, should catch the loop formed.
The gap between the looper blade and the needle should be as small as 0.05 mm. This gap can be set by loosening the left looper screw B and carefully turning the looper as it approaches the needle. Do not loosen screw B too much, the looper should turn with little force. After achieving the required clearance from several attempts, do not forget to lock the mount (B).

Taking hold of the needle loop, the left looper pulls it along its blade, and the right looper R is already moving towards it to enter the loop created by the left looper.
The nose of the right looper follows the notch on the back of the left looper, getting as close as possible to its eye and blade at the same time.
If you draw a horizontal line at this point, the nose of the right looper should be below the eye of the left looper and the gap between the blades of both loopers should be 0.1. 0.15 mm.
It is possible to get confused in these terms and provisions, but it does not work out any easier.
Now it remains for the needle to remove the loop from the right looper, and the overlock will work like a clock.

When the needle enters the loop of the right looper, the clearance between the needle and the looper blade should also be 0.1. 0.15 mm, and the distance between the eye of the right looper and the needle point (when they are at the same level) is approximately 0.3 ... 0.5 mm.
The right looper does not have an adjusting screw to bring its nose closer or further away; it is rigidly fixed with a screw to the platform. It is adjusted in a trivial way - by careful bending in one direction or another. But the left looper cannot be folded like this.

It should be noted that there is only one correct looper and needle position that a Class 51 overlock will perform flawlessly.

All of the above parameters are only a rough guideline for the overlock setting. Perhaps some of the parameters for your machine will differ, since a lot also depends on the cam setting.
Rotating the cam 1-2 degrees will change the position of both loopers at the same time. Therefore, in order not to break the loopers when they meet, this adjustment should only be done by an experienced tuner.

The reason for the sudden appearance of gaps may be the movement of the needle bar together with the needle up, check this parameter first. Perhaps simply lowering the needle bar (screw I) 0.5-1.0 mm will eliminate the gaps.
Sometimes, threads that are not suitable for the overlock can also cause skips in the stitches. See Sewing threads, which is better ?.

Correct threading is essential for the proper operation of the sewing machine, especially for an overlocker. Tweezers are used to thread the overlock loopers.

First, thread the right (upper looper R), (fig. P). Through two holes 1, between the tensioner washers 6 into the thread feeder 8, under the bracket of the wire thread guide 9 and into the eyes of the looper away from you.From the stand, with the bobbin of the lower (left) looper L, the thread is threaded (Fig. L) into hole 1. Next, into the eye of the thread take-up 3, and into the hole of the thread guide 8, located on the overlock cover. Then it is passed through holes 9 and 10 in the side cover, then through the tensioner 12. It is passed through the tubular thread guide 13, under the thread take-up device 14 and into the eyes of the left looper away from you.
The thread of the needle from the stand from the bobbin is passed through hole 1 in the thread guide plate 2, between the washers 3 of the tension regulator, holes 4 on the left side of the plate 2 in front of the shaped thread take-up device 5. Then, through the eye 6 of the thread feeder, fixed on the leash of the needle mechanism, between the tension washers 7 and into the eye of the needle 8 away from you.

The overall movement of the rack is controlled by an eccentric, which is adjusted by two screws located deep in the eccentric housing. The eccentric is attached to the main shaft of the overlock.
In the case 1 there is a groove for the passage of the slider (eccentric 4), the displacement of which leads to a change in the stitch length (more often, less often). This displacement is done by screw 2 after loosening screw 3.

Dull knives “tear” the edge of the fabric rather than cut it, which is often the cause of most stitching defects. Unfortunately, you cannot sharpen the knives yourself. But, using this instruction, you can remove them and put them back. You need to sharpen the knives on a special machine with fixing the sharpening angle. Contact the craftsmen who make keys, they have such machines, but keep in mind that not everyone will undertake to sharpen overlock knives.

General recommendations for the installation of knives.
The lower knife should be flush with the throat plate. The upper knife should press firmly against the lower knife with its entire cutting edge and fall (go) beyond the edge of the lower knife by 1.0 -1.5 mm, no more.
Just in case, we provide fragments of the factory instructions. On the fifth try it will be easier to understand it.

Overlock class 51 can work on any thread. This is another feature and advantage of it. Even the old bobbins of cotton thread that have survived from the Soviet era are nothing to him. We have a whole box of such threads (one customer gave it to us) and now our old class 51 overlock has already reworked half of the box. But still, he "loves" the big tapered bobbins of number 35 more. Works great on Ideal threads and other brands wound on small spools. It is only advisable to put threads of the same type and thickness on all loopers and the needle, although it is not necessary. All you need to do is adjust the stitching with the thread tensioner. Each type of thread has its own "resistance" and therefore, it is imperative to adjust the tension of each of them separately.
The incorrect tension of each thread separately sometimes causes gaps, not to mention the appearance of the stitch.

Sewing machine Merrylock 009
This article provides only a description of the device and the main characteristics of the Merrylock model 009 cover-frame.

Overlock Janome ArtStyle 4057
Overlock Janome ArtStyle 4057 performs 3- and 4-thread overlock stitches. It is used for overcasting any fabrics, including knitted fabrics.

Preventive repair, setting up overlocks with your own hands
You can and even need to be able to set up an overlock yourself. Overlock repair is needed only in those cases when there is a "failure" of the work of some nodes. Basically, all overlock problems “lie on the surface”. Incorrectly selected threads, dull needles, improperly adjusted thread tension, etc.

Which overlock to buy
You have 51 classes, but would like to purchase a modern four-strand overlocker? Modern overlockers are capable of many types of overlock stitches, including various decorative stitches. They sew over complex knitted fabrics with high quality, have illumination, are light and beautiful.Use our recommendations, maybe they will help you choose an overlock.

Which carpetlock to buy
When the 51 class overlock was released, no one even imagined that such a sewing machine as a carpetlock would appear. Need to overcast or need a cover stitch? All this can be done by one machine - a carpetlock. If necessary, the rug can be used as a chain stitching machine.

How to choose a sewing machine
Decide what operations your sewing machine must perform. If you are sewing clothes, your machine must have a buttonhole making operation. Almost all machines have this operation, the only difference is in the mode in which it performs them: automatic, semi-automatic and manual.

Overlock VOMZ 151-4D
Overlock class 51, overlock VOMZ, "Prima" - these are overlocks that often have to be adjusted. This article contains a looper adjustment diagram for a VOMZ overlock. It can also be used to adjust the loopers of other brands of overlockers, however, only as a general idea of ​​how the overlock loopers interact.

Overlock device and instruction Prima
Household overlocker Prima, depending on the model, performs a three-thread or four-thread stitch. Device, instruction of overlock Prima, care and repair.

Do you have a sewing machine and love to sew? Then this site is for you. Professional craftsmen will tell you how to make minor repairs to a sewing, knitting machine. Experienced technologists will share the secrets of tailoring. Review articles will tell you which sewing or knitting machine to buy, a mannequin iron and many other useful tips you will find on our website.
Thank you for viewing the entire page.

Any overlock is much more complicated than a sewing machine. It is only a master with special knowledge, skills and experience that can set up many parameters of the overlock units, moreover, only a master with special knowledge, skills and experience can repair mechanisms. It is almost impossible to make adjustments with your own hands, for example, the interaction of the overlock loopers. However, it is not always necessary to repair or adjust its knots, sometimes it is enough to correctly adjust the thread tension and the overlock will again overcast the fabric with high quality.

Almost all overlocks, except for the old model 51 class industrial overlock, are very sensitive to thread tension, and when switching to other thread thickness and quality, the tensioners have to be adjusted. This is precisely the most common reason for poor overlock performance. But there are other reasons too, let's look at them.

First, let's figure out how the overlock seam is formed.
The overlocker uses two loopers and a needle (three-thread stitch) to form a stitch. In modern models of knitted overlockers, two needles are installed, due to this, the overlocker performs a higher quality four-thread overlock stitch.
When adjusting the thread tension in a stitch, it is important to understand which one belongs to the needle (s) and which belongs to the loopers.

This diagram clearly shows that the needle thread (I) does not overcast, but grinds, but overcast the cut edge of the looper thread (P). The green thread (bottom) belongs to the left looper, and the beige thread (top) belongs to the right looper.

Be sure to figure out which looper is setting the bobbin thread and which is the upper thread. And remember which tensioner adjusts each one. Then, just by looking at the line, you will immediately understand which thread needs to be tightened and which one to loosen.
Most often, when a bad stitching appears, random rotation of all the handles in a row begins, completely knocking down the tensioner setting. As a result, the overlock begins to skip and sometimes break the thread.
And yet, having studied how the overlock seam is formed, you will get rid of the illusion that the sewing machine can sew an overlock seam.The sewing machine can only imitate the overlock stitch because it has a completely different stitching principle.

Some instructions provide for adjustment of the loopers, and give parameters for their setting in relation to the needles in case of failure of these gaps or when replacing the loopers. As a rule, these parameters are indicative, so to speak, ideal. A master who repairs overlocks has to experimentally bring them to the desired value, so this type of repair is recommended for a professional.

All our recommendations in the overlock repair section are generalized, universal and will fit any overlock model, but do not forget to carefully read the instructions for your model, where you can find information on setting up, lubricating, choosing the type of needle and more.

If you experience gaps or thuds, the needle is most likely dull or bent. A dull needle can cause many problems. The overlock needle is a very important detail, many parameters depend on its condition, in particular, the gap of the needle with the looper is the main parameter for the overlock stitching without gaps.

A blunt needle can be identified by running your thumbnail along the tip of the needle on all sides. The nail will definitely find a bent place on the tip. You can use a magnifying glass to inspect the needle point.

If the needle is bent, do not try to straighten it, the overlock setting is very accurate and such needles are not allowed.
Whether the needle is bent or not can be determined by placing it on a flat surface. Examine the needle from above and from the side: 1 - parallel lumen; 2 - flat surface (glass, etc.)

Pay particular attention to which type of needle is installed in the overlock. It is imperative to comply with the requirements of the manufacturer's instructions - use the types and brands of needles recommended by the factory.
In addition to the fact that the needles can be with a round or sawn flask, they can still differ in the length and thickness of the flask, the length of the needle itself and other parameters.
If the overlocker uses needles with a round flask (overlock class 51), you need to replace the needle with the same thickness and length of the flask when replacing.
See Sewing Machine Needles.

The sizes and types of needles used are indicated in the instructions, sometimes their brands are indicated on a sticker located on the inner surface of the hinged cover. If not, then write down the type of needle on a small piece of paper and glue it with transparent tape on the body.
In any household overlock, the needle is installed with a long groove towards itself, or with the sawn-off part of the flask away from itself.
It is imperative to install the needle as far as it will go, and if you have two needles, they are often offset (one higher than the other).

Overlock sewing threads play a vital role in the overlock process. If you use threads of different quality or thickness, this will immediately affect the tension and, therefore, the stitch pattern will change. The overlocker is very sensitive to thread tension, and the slightest change in one of them can affect all the others.

Try not to use cotton or thick threads. The thinner and more elastic the thread, the easier it will pass through the sewing fabric, needles, loopers, and the better the stitching will be.
Threads on tapered bobbins (35) are considered the most optimal for high-quality overlock operation. They are thin, strong and resilient and can be easily removed from the tapered bobbin.

It is ideal to use threads of the same brand, changing only the color. But in practice this happens rarely, therefore, when replacing threads with a different type or thickness, their degree of tightening may change. In the event that the stitch turns out to be very ugly and not "correct", we recommend to loosen all the tensioners and at the slowest speed, gradually increase the tension of each thread, periodically checking which thread, and how much you need to tighten.

In “hard” cases, when adjusting the overlock stitch, it is better to use threads of different colors in order to clearly see the tension of each of them, and replace them after adjustment.

The fabric does not move - the presser foot pressure is too weak.
If the fabric is too thin, the pressure of the foot must be reduced, otherwise the fabric will pucker. Increase the foot pressure when sewing thick fabrics. In general, the presser foot should not be changed unless clearly necessary.

Broken thread - the threads are not threaded correctly.
Thread the threads carefully, especially those going through the loopers. In some models of overlockers, threading into the loopers is a rather complicated procedure, and you cannot do without specially curved tweezers. It is imperative to insert the thread into all the attachment points indicated in the diagram. It is enough to skip one fastening and the stitching will be uneven.

The thread is tangled. Check the spool, maybe the thread came off the spool and caught on the body part. Check the thread guides and the entire thread path.

Too much thread tension is one of the reasons for thread breakage. Thread breakage, skips occur when using a different type of needles (see above).

Skip stitches: the needle is bent or blunt; the needle is installed incorrectly; a needle is used that is not recommended for use by the manufacturer; the thread is not threaded correctly or one of the thread attachments is missing; the pressure of the presser foot is too weak.

Uneven stitches - the thread tension is incorrectly adjusted.

The fabric wrinkles - too much pressure on the fabric; the thread is not threaded correctly or is tangled; the thread tension is too tight. When sewing thin and light fabrics, loosen the thread tension in the overlock stitch.

After prolonged operation of the overlock, clean the looper compartment and other accessible areas from trimmings, fleece and other contamination (oil stains). Cleaning is preferably done with a stiff hair brush (for glue).
By the way, excess oil in the area of ​​the needle can ruin the fabric being processed. Be careful to lubricate the parts that come into contact with the fabric.

Overlocks should be lubricated at least once every six months, and with intensive use once a month. It is convenient to use a medical syringe instead of a grease can. With a long needle, you can always crawl into hard-to-reach places, and less oil is consumed.

The instructions provide a lubrication scheme, but you can follow a simple rule - lubricate any accessible places where there is friction of metal parts, even if they are not specified by the factory in the instructions.

In order to “thoroughly” lubricate all the overlock assemblies, it is sometimes necessary to remove the protective covers of the case, but if they are difficult to remove, you can get by with the factory labels for lubrication.

Overlock lubrication should be given more attention than a sewing machine, as the overlock operates at higher speeds and the lack of lubrication in some units leads to overheating and even seizure.

What is the difference between a carpetlock and an overlocker and a coverlock
An overlocker is practically no different from a carpetlock. It can also sew overlock seams. But thanks to the special design, in addition to the overcasting seam, the carpetlock can also perform a flat seam and even a stitching one. Since a carpetlock is much more complicated than an overlock, it can be repaired only in a specialized service center.

Which overlock to buy
If you do not use an overlocker often, you do not need to purchase an expensive model overlock. Any overlock for 7-8 thousand rubles will perfectly overcast various fabrics and, most importantly, in the event of a breakdown, repairing the overlock will be cheaper.

Inexpensive Sewing Machine: Pros and Cons
For many who are going to learn how to sew, the question often arises "What to buy a sewing machine", preferably inexpensive and good.In this article, we will figure out whether such a combination is possible - "an inexpensive and good machine" and how an inexpensive sewing machine that costs 3-4 thousand rubles differs from a machine that costs 30 thousand.

We sew knitwear without gaps and looping
Many who tried to sew knitwear on an ordinary sewing machine noticed that the machine often refuses to make a beautiful and even stitch. There are gaps in the knitted stitching, the lower thread loops and sometimes breaks. Why is this happening and how can you fix it?

Overlock class 51
Overlock class 51 is perhaps the most common brand of industrial sewing machine used in everyday life, in small ateliers. Although morally this technique has long been outdated and many modern fabrics simply cannot be processed with high quality, nevertheless, its use is sometimes justified, especially for processing coarse and thick fabrics.

How to sew on a curtain tape
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How to sew curtains with your own hands
Processing an organza curtain of a simple model for a window in the kitchen is indeed available to many who have little experience and a sewing machine. But to sew curtains in a living room or a hall with a lambrequin is the lot of professionals who have not only knowledge, but also experience.

How to hem jeans
How to cut jeans that are too long and use a household sewing machine to finish a hem stitch consisting of several layers of coarse denim.

The 51 class overlock is perhaps the most common industrial sewing machine used in everyday life, in small ateliers. Although morally this technique has long been outdated and many modern fabrics simply cannot be processed with high quality, nevertheless, its use is sometimes justified, especially for processing coarse and thick fabrics.

One of the advantages of the 51 class overlock is its affordable price. For 3-4 thousand rubles you can buy quite a “decent” used overlock. One more thing - the overlocker can overcast fabrics with any thread, including cotton, still of the Soviet style.

Sometimes it is necessary to perform minor repairs, overlock settings. All instructions for it are lost, there is practically no literature available, and the services of a master are sometimes more expensive than the overlock itself. For such a case, we offer you some small recommendations.

Technical characteristics of the 51, 51A class overlock.
Overlock class 51 and 51-A class are used for overcasting cuts of knitted, dress, and underwear items with two- or three-thread chain overlock stitch.
Stitch length from 3 to 6 mm; the thickness of the materials in a compressed state under the presser foot is up to 2.5 mm; brand and type of needle - 0029 No. 60-70.
The overlocker has a needle mechanism and two loopers. It is possible to replace the right looper with a spreader, then the overlock will use only two threads.
The 51-A class overlocker is a modification of the class 51 machine and differs from it only in that it uses a differential tissue movement mechanism, which consists of two parts. The horizontal movement of the front strip is greater than the back one, due to which the fabric is stretched during the overcasting process. To put it simply, such an overlock will efficiently overcast knitted fabrics. Overlock seams will be elastic and stretchable. Pay attention to this if you need to buy a 51 class overlock.

This industrial sewing machine has a centralized wick lubrication mechanism located under the machine bed. For this purpose, a crankcase is cast from below under the main shaft in the housing, which is periodically filled with oil. The mechanisms located above the machine platform are lubricated with an oiler.

It is recommended to lubricate the 51 class overlock at least once a month with intensive use. All rubbing metal assemblies need to be lubricated, preferably by constantly turning the shaft during lubrication.It is very convenient to lubricate sewing machines and overlock with a medical syringe.
The overlocker provides adjustment of the thread tension, the pressure of the presser foot on the material, the length and width of the stitch.

Correct threading is essential for proper overlock operation. To form a three-thread overcasting stitch, thread the needle thread in the following order:
The thread from a spool or bobbin on a spool stand is first passed through the two rear holes in the thread guide plate.
Pull under the washers of the tension regulator on the same plate.
Through the peephole of the posterior horn of the thread guide plate towards yourself.
On the left side of the thread take-up device into the eyelet (L) of the second horn.
To the left into the hole (P) of the thread guide on the needle bar.
Down into the eye of the needle (I) straight away from you, leaving the end of the thread about 5 cm long under the foot to start sewing.

Threading the right overlock looper is clearly shown in the photo and diagram. We will only comment on some points.
E - note that the thread is threaded from the bottom up.
K - the thread must necessarily pass through this knot, you cannot skip it.
F - note that at first the thread is put into knot F, and then into knot K, and then goes to the looper.

Threading the left looper is more difficult because access to the looper and thread guide (E) is limited. Use long tweezers and, if possible, do not pull out the old threads from the overlock, but pull them along with the new threads. It is advisable to stretch one thread at a time.
A - the thread comes out of the sleeve of the body.
D - this thread holder has a slit, and the threads can be “snapped in”, it is not necessary to put it into the hole. B - notice how both threads pass through the loopers. The threads of both loopers must come out from the back of the looper.
To form a two-thread overcasting stitch, replace the right looper with a spreader without threading.

Trimming the edge of the sewn fabrics is carried out with two knives: the upper movable knife 4, mounted on the swinging arm of the knife 7, and the lower 11, which is fixed in the block 12 on the machine body.
The position of the upper knife 4 is set depending on the width of the overedge.
The upper knife is fixed in the holder 5, which can be rearranged in the ears of the lever 7. To move the knife, unscrew the screw 6 of the clamp 10 on the holder 9 with a screwdriver and move the holder to one side or the other, depending on the overcast width.

To ensure normal cutting of the material, the upper knife 4 with its plane must fit tightly, without a noticeable gap, to the plane of the lower knife 11.
After the upper knife 4 is set in accordance with the required overcast width, the lower knife 11 is brought to it, this movement of the block 12 is carried out by means of the lower knurled screw 14. The front screw 13 on the body, securing the block, is preliminarily loosened with a screwdriver.
Both the lower and upper knife can also be adjusted vertically after releasing the fixing screws: 8 for the upper knife and 1 for the lower knife.
The lower knife is installed in the block so that its cutting edge is at the level of the throat plate. The upper knife is installed so that its cutting edge overlaps the lower knife by approximately 1mm.
When changing the width of the overedge, it is necessary to adjust the position of the plate 2 on the presser foot, having released the pre-fixing screw 3.

A 51 class overlock that has been adjusted and tuned by a master rarely needs repair. His knots are strong enough and do not randomly go astray. The reason for the poor performance of an overlock is usually associated with inept use of this industrial machine.

1. First, keep the overlocker perfectly clean, especially where the looper thread runs. Feathers and dust impede the uniform sliding of the thread and cause “looping” and sometimes breakage of the thread.

2.You need to change the needle in the overlock, not when it bends or breaks, but periodically, since the condition of the needle directly affects the quality of the overlock stitch.
For thick fabrics and reinforced threads, use a thicker needle, no. 100 - 120.
51 overlock needles are custom size. They are noticeably shorter than other industrial needles and have a thicker bulb. Using a different type of needle will result in skips, knocking during sewing, thread breakage and needle breakage. By the way, knocking while working is a bad sign. This means that you are overcasting too thick and the right looper is hitting or hitting the overlock foot with its nose. Do not overcast too thick sections of jeans, drape fabrics. This can damage the looper.

3. The most common cause of poor overlock performance is improper thread tension or different twist and thickness threads. The overlocking class 51 is very “undemanding”, but still try to use threads of the same twist and thickness, threads from large tapered bobbins are best suited. To adjust the thread tension, you must first loosen everything, and then “tighten each of them. It is very convenient to use threads of different colors for this adjustment.

4. Incorrect threading, especially in the loopers, will also cause the overlock to malfunction.

5. Work on the 51 class overlock is carried out in the same way as on conventional stitching machines. Usually, after the end of the operation, the threads are not cut, but new parts are placed under the foot and the overcasting continues. This reduces the consumption of threads and eliminates the possibility of accidental pulling of threads from the eye of the needle or loopers, which causes a loss of time for re-threading the machine.
The direction of the fabric when sewing on the machine with a knife must be precisely defined, otherwise the edge of the parts may be cut unevenly.

We sew knitwear without gaps and looping
Many who tried to sew knitwear on an ordinary sewing machine noticed that the machine often refuses to make a beautiful and even stitch. There are gaps in the knitted stitching, the lower thread loops and sometimes breaks. Why is this happening and how can you fix it?

What is the difference between carpetlock and overlock
How to figure out what you need to buy - overlock or carpetlock, what model and firm, what operations should be performed on it? So many questions arise for the uninitiated in the subtleties of the sewing technique of the buyer.

Tips for setting up an overlock
Even a household overlock is much more complicated than sewing machines and it is almost impossible to set it up, moreover, to repair an overlock without special knowledge and skills. However, overlock repair or adjustment is not always required, sometimes it is enough to simply adjust the thread tension and it will again overcast the fabric with high quality.

DIY sewing machine repair
A sewing machine more often than an overlock requires repair. As a rule, this is due to a violation of the rules for the operation of the sewing machine, namely, sewing thick and coarse fabrics that are not provided for in the instructions, using needles and threads that are not intended for this model of the sewing machine.

Seagull sewing machine
The sewing machine "Chaika", as well as the 51 class overlock, are still the most popular models of home sewing machines. Sometimes this is justified, since both of these machines are quite reliable and they practically do not have breakdowns of metal parts.

Which overlock to buy
A modern household overlock is not so expensive, and compared to a 51 class overlock, its capabilities are several times higher. Almost all modern overlockers use 4-strand stitches, but can sew 3-strand and 2-strand stitches. And the presence of a differential rail allows high-quality overcasting of knitted fabrics.

Inexpensive Sewing Machine: Pros and Cons
In this article, we will figure out whether such a combination is possible - "an inexpensive and good machine" and how an inexpensive sewing machine that costs 3-4 thousand rubles differs from a machine that costs 30 thousand.

How to replace an overlock belt with your own hands
The overlock motor belt sometimes differs from the sewing machine belt. How to replace an overlock belt with your own hands.