Overlock 51 classes with confidence can be called one of the most widespread varieties of sewing machines that can be used not only in large-scale production, but also in everyday life and in small ateliers. Despite the fact that such a technique is already considered very outdated, it is very good to work with thick and rough types of fabrics. However, this device can no longer cope with high-quality materials.
Overlock 51 classes: specifications
This type of sewing machine is designed for overcasting sections of knitted, linen and dress fabrics with a two-thread or three-thread sewn seam of a chain type. In this case, the standard stitch length is usually from three to six millimeters, while the thickness of the material in the compressed form should not exceed two and a half millimeters.
Overlock class 51 is equipped with a needle mechanism and two loopers. If you want to replace the right one with an expander, then this sewing machine will use only two of the three threads.
There is also such a model as an overlock 51-A class. He is a more advanced variety of this type of sewing machines. Its main difference is the presence of a differential mechanism for moving tissues. Such a mechanism usually consists of two parts, due to which the materials are stretched during the work process. This mechanism will do very well with knitted fabrics, so be sure to consider this before you make a purchase. After all, all the overcast seams will be very stretchable and elastic, which is very important for knitwear.
Gear lubrication
Overlock class 51 is an industrial type sewing machine . It is characterized by centralized wick lubrication of the mechanisms that are under the platform of the product itself. In order to carry out the lubrication process, you need to find the crankcase on the bottom of the product and fill it with oil. But do not forget about the lubrication of the upper part of the mechanisms that are located above the platform itself. You need to do this with the help of a special nipple.
Three-strand overlock must be lubricated at least once a month, provided the product is used very intensively. Be sure to lubricate all parts of the machine that rub against each other during the work process. Try to constantly rotate the shaft during lubrication. Experts recommend conducting this process using an ordinary medical syringe. With its help, it is very simple, fast and convenient.
Please note that this type of sewing machine is equipped with a mechanism for adjusting the tension of the threads, as well as the degree of pressure of the presser foot on the material you are using. You can also independently adjust the width and length of the stitches.
Proper threading of the needle thread
Filling class 51 overlock is a very important process. It is from him that the correct operation of the unit will depend. If you plan to use a three-thread overcast stitch for work, then follow these steps in the order below:
- Take the thread from the bobbin or from the spool located on the spool stand, and to begin, pass it through the two rear holes in a special plate to guide the threads.
- Now drive it towards yourself on the same plate, but under the regulator washers.
- Next, pass the thread through the peephole of the posterior horn onto yourself on the same plate.
- Now start working on the left side. Guide the thread to the eye of the second horn from the thread take-up.
- Pass the thread to the left to the needle bar.
- Insert the thread into the eye of the needle directly in front of you, leaving about five centimeters under the foot itself.
Proper looping interactions
In fact, setting up this sewing machine is not so simple. Most often, a beginner can not do it. Usually one instruction is not enough, all knowledge comes with experience. For the correct operation of the overlock, it is very important to configure the correct mutual operation of the needle and loopers. Pay attention to the main tuning principle: when meeting, all the loopers and the needle should have the smallest possible clearances.
While the looper enters the loop that forms just above the eye of the needle, the needle itself must carefully fit into the loop formed by the looper.
An important landmark when setting up an overlock of class 51
The left looper is the most important guide when setting up this sewing machine. While the needle will lower to its lowest position, the looper should also take the leftmost position at a distance of about five millimeters from the needle. So, when the needle rises a couple of centimeters up, a loop will begin to form, which this looper should capture. In this case, be sure to pay attention to the gap between it and the needle itself. It should be no more than 0.05 mm. Such a gap can be set independently. To do this, you will need to loosen the screw of the left-most looper as much as possible, and very carefully turn it to the needle. It is not always possible to establish the necessary clearance on the first attempt. Do not be discouraged, such skills will come to you very soon, along with experience. After you have set the required clearance, do not forget about the screw. It must be tightened.
Right looper
Now, when the left looper grabs the loop, he begins to pull it along his blade. At the same time, the right looper is moving toward him, which should enter the loop of the left. For properly arranged work, the only thing left for the needle is to remove the loop from here.
Pay attention to the distance between the tip of the needle and the eye of the right looper. When they are on the same horizontal line, the distance between them should be about 0.3-0.5 mm.
Setting the right looper is actually a lot easier than the left looper. It does not have a special screw for adjustment, which means it will be very simple to adjust it. To do this, just gently bend it in the direction you need. Do not forget that this rule applies only to the right looper. In no case do such a fraud with the left, otherwise you risk breaking the sewing machine.
The main reasons for omissions
Overlock needles can have only one correct arrangement together with loopers. Only in this case the entire unit will provide you with high-quality and productive work. All the numbers in millimeters described above are just indicative indicators. In fact, all products may differ slightly from each other, so the numerical parameters will be slightly different. However, in any case, all errors will be insignificant.
Also, the numerical parameters depend on the cam. If you turn it even one or two degrees, then the position of both loopers will be slightly changed. However, in no case do not carry out such a procedure yourself. Only a specially trained master can do this.
The most common and most common cause of omissions may be the simultaneous upward movement of the needle bar along with the sewing needle. Be sure to check this parameter. Indeed, it often happens that even lowering the needle bar a little (only 0.1-0.2 mm), you can eliminate the cause of the omissions.
By the way, one more common reason for omissions can be incorrectly selected threads specifically for your overlock model. Take full responsibility for their choice, and you will not have problems with skipped stitches.
How to adjust the stitch length
To adjust the stitch length, you need to find a rail on the overlock that moves due to the action of the eccentric. This part is adjusted using a few screws, which can be found in the body of the sewing machine itself. However, again, it is not recommended for a beginner to carry out this procedure. Better ask the master and follow his actions. And only then try to do it yourself.
Overlock knives
Very often, the dull knives of the sewing machine cause line defects. Therefore, you need to sharpen them in a timely and correct manner. At home, this will not work.
To this end, you can contact the masters involved in the manufacture of keys. After all, it is they who have such machines available.
A few words about belts
Usually, a belt for an overlock of class 51 lasts a very long time, up to several tens of years. However, the period of its use primarily depends on the frequency of use of the sewing machine. You may not have to change it very often, but you need to be able to adjust its tension.
Modern models of belts usually have special teeth, so they need to be tensioned extremely rarely. But models without them need more frequent tension. More often than not, on the 51st overlock you can find exactly the smooth type of belts. However, if you have the opportunity, it is better to replace it with a gear.
How to correctly adjust the overlock belt tension
In no case do not tighten the belts too much, as this can lead to noise in the operation of the unit, as well as to a large load on the bearings. And this, in turn, will lead to very fast wear of parts, and the belt itself, which can tear over time.
In order to tighten the overlock belt well, it is enough to check the tension with your finger, but only after the fastening screws are tightened. The belt should bend when you exert a little effort.
There is an even simpler way to check the tension. You can carry it out during the work itself at the sewing machine. A correctly tensioned belt will not whistle and hum.
The main differences between the man and the sewing machine
Nothing lasts forever, and your favorite sewing machine too. Over time, you have to change some parts for overlocks. Consider the main types of breakdowns, as well as the most common problems:
- It is very important to install the needle correctly. Incorrect installation will lead to problems with looping, or to rupture of threads. Before calling the wizard, check that the needle is installed correctly.
- Choose the right thread and fabric for your machine. After all, the wrong choice can lead to damage to the material and to damage to your unit.
- If the needle plate is broken, some parts may need to be replaced. Only a specially trained specialist can perform it.
- Quite rarely, but there are still cases when the motor fails. This is a very serious failure requiring a complete core replacement.
- If the pedal rheostat is broken, then you will have to replace the entire pedal structure.
Thread selection
Important advantages of this unit are its durability and relatively low cost. Overlock, the price of which is about 8,000-10,000 thousand rubles, will last for more than one decade.
Overlock 51 class is also characterized by the fact that it can work with absolutely any thread. Even old Soviet threads will do. However, the cone bobbins of the thirty-fifth number are most to his liking. Try on the looper for the overlock, and also put the needle of the same type of thread of the same thickness. Of course, this is not necessary, but nevertheless, it is desirable.
Please note that each type of thread has its own resistance, so adjust the tension of each of them separately from the others.
If you pick up the wrong tension, there is a high probability of gaps, as well as the terrible appearance of the line itself.
Overlock Advantages
Overlock, whose price is relatively low, has a huge number of advantages over other sewing machines. What exactly attracts seamstresses in it?
With it, you can get overcast seams, which you can’t do with a regular machine. Overcasting seams is a very complex process, and the overlock does it very well.
This unit works very quickly, and, most importantly, very carefully. With it, you can also create blind and decorative types of seams.
However, pay attention to the fact that any sewing machine must be handled very carefully, otherwise it is likely to get serious injuries. But, despite the risk of injury, the overlock is still very convenient to use. If you want this equipment to serve you for a long time, carefully look after it and repair it on time.