Cover stitching machine
When sewing knitwear, jerseys and split fabrics, the correct processing of the edges is an important issue.
It cannot be performed on an electric or electromechanical sewing machine due to the inelasticity of the stitch produced, which leads to deformation of the finished product.
For high-quality processing of seams in knitwear, special sewing machines were created. They produce even stretch stitches on stretchy fabrics.
The cover stitch (another name is a cover stitch) machine is designed to make reliable flat seams on elastic and flowing materials.
Often it is used for hemming the bottom of knitted T-shirts, T-shirts, chiffon blouses, underwear, sleeves and collars on shirts, etc.
Such devices have much in common with functional overlocks and coverlocks, which are intended for processing or bending sections in products.
Flat seams are used when carrying out various sewing works that are associated with the processing of sections in products made of stretch and knitted fabrics, in the manufacture of home textiles – curtains, bedspreads, tablecloths, sheets, covers, etc.
The special design of the cover sewing technique ensures uniform flat stitches, which are obtained by using 2-4 needles and loopers.
Each model of the device is equipped with a certain set of needles of the upper row and a lower looper to create a flat seam in its various modifications. In addition, such devices allow you to perform a chain-type stitch.
There are models that are additionally equipped with an expander or threader, which is located in the upper part of the case.
The process of making a flat seam is simple – the needles of the upper row are immersed in the fabric, the looper removes the upper threads from them and moves to the extreme position.
In the reverse order, when immersed in the fabric, the needles remove the threads from the looper and return to their original position.
How to choose a sewing machine
When choosing such sewing equipment, it is recommended to pay attention to the functional features and technical parameters.
Reliable equipment from trusted manufacturers with a guarantee of long-term operation is distinguished by a wide range of options for working with different types of fabrics and high quality workmanship.
Platform and separate conveyor
For ease of use, this type of sewing equipment is equipped with a special platform, which is intended for processing complex elements or individual parts of products.
It will help to qualitatively trim the bottom, legs, sleeves, lapels, collars, wide straps.
Modern models of devices are equipped with three types of platforms:
- Flat removable platform. It is used for general operations, for processing the bottom in products with closed and open sections, for stitching with an oblique trim.
- Platform with a recess for the binder. It is suitable for high-quality edging of things made of soft fabrics with an oblique trim.
- With a platform in the form of a cylinder. It can be solid or with a recess, used for quick stitching of narrow and long parts, for sewing children’s underwear.
Separate feed dog allows you to collect and stretch the sliding material to obtain the desired type of gathers and folds.
Working distance between outer needles
This is a key characteristic that determines the required width of the stitch to be produced. The standard width is 5.5 and 6.5 mm. Covering devices are available: for 2 needles (seam width 5.5 mm) and for 3 needles (seam width 6.5 mm).
Devices with two needles for 3 threads allow you to sew lines of the same type, and devices with three needles for 4 threads – several variations of seams. Devices with one needle for 2 threads are used for simple stitching of knitwear parts.
If necessary, you can install only two needles, changing their position to obtain different types of flat stitches.
Types of flat seams
Four types of professional flat seams are performed on cover stitching machines:
- Triple and wide – 5.6 mm wide;
- Narrow (left and right) – width 2.8 mm;
Automatic needle threading mode
The working mode is used to automatically thread the needle eye in expensive models of devices.
Fabric feed type
The machines have a function of differential feeding of fabric for the manufacture of the product.
In the standard scheme, the rear and front conveyors feed the fabric at the same speed, some devices provide a partial change in speed for one conveyor.
This allows you to perform the necessary operations – create assemblies or stretch the canvas.
There are two options for thread tension in the sewing technique – manual and automatic. Automatic simplifies the process of sewing products and minimizes the occurrence of possible sewing errors.
With manual adjustment, the tension force for each thread is different, so this method requires skill and an eye.
Bottom looper threader
In sewing devices, a special device for threading the looper is provided, which is located in the lower part of the body.
Presser foot pressure adjustment function
The cover stitching machine has a function to adjust the degree of pressure of the sewing foot on the fabric when it is fed. For flowing and splitting tissues, the pressure is maximum, for dense tissues it is minimal.
Different models of devices have a different degree of presser foot pressure, so the adjustment is carried out manually or automatically. Automatic adjustment takes into account the type of tissue being fed and determines the degree of necessary influence on it.
Some models are equipped with an additional function of adjusting the force of tissue puncture with working needles. It ensures that the correct stitches are sewn at the selected speed, regardless of the thickness of the fabric.
Presser foot height
This distance is determined between the working surface of the machine and the uppermost position of the foot, to which it rises. The height is from 3 to 15 mm. The height is adjustable by smooth or stepped switching.
This technical parameter depends on the specific model of the machine and determines the total number of work stitches that can be completed in one minute. The average sewing speed is 1000-1500 stitches per minute.
The distance between adjacent punctures, which are made longitudinally, determines the length of the finished stitch. Short stitches are reliable and durable. In addition, the length directly depends on what the seam is intended for.
The minimum stitch length is 1-3mm and the maximum is 3-6.5mm.
A parameter that is functionally similar to the previous one, since it determines the width of the finished seam. Wide stitches are needed for decorative topstitching, so the minimum value is 1-5.6 mm, the maximum is 3-15 mm.
Number of work operations
Modern models of machines provide for the implementation of many work operations – from 2 to 51.
The device provides thread trimming after the sewing process is completed. In budget machines, it is represented by a plate with a sharp blade, which is installed at the bottom of the working platform.
In expensive models, it is implemented in the form of an automatic control button that trims the threads.
For ease of use, each thread guide has an individual color marking on the side of the body.
Container for scraps and threads
Some models are equipped with an internal container, which is designed to collect fabric scraps and threads left after sewing.
Product power and weight
This indicator determines the maximum energy consumption during operation. Modern cover-type machines are equipped with a powerful working mechanism and electronic control, which ensures the correct functioning of the device.
The operating power of the device is from 70 to 250 watts.
Without auxiliary tools and accessories, the weight of the machines can be from 5 to 12 kg.
Protective storage case
Reliable storage of the device provides a protective case of two types – soft and hard. Soft cape is made of natural breathable fabric. Provides protection of the working mechanism from dust and moisture.
The hard case of the frame type provides protection of the body of the product from mechanical impact.
According to the general classification, stitching machines are for domestic and industrial use. Household devices are suitable for use at home, for small private workshops and tailoring studios.
Industrial designs are used at large manufacturing enterprises for mass sewing of knitwear. Household models are equipped with 1-3 needles, industrial options – from 2 to 8.
Unlike household appliances, industrial sewing equipment of this type is large in size.
It is equipped with adjustment nodes, thread tensioners, multiple thread bobbin stands and a threader in the upper part of the body. The threader is designed for laying the thread with the right side of the flat stitch.
In addition, industrial devices are installed on a special table, under which an electric drive with a double pedal is placed.
Industrial devices are used for tailoring, knitwear, underwear and bed linen and home textiles. They are focused on performing highly specialized sewing operations.
High-quality sewing equipment is equipped with reliable ergonomic controls – mode switches, thread tensioners, working paws, needles and loopers.
When choosing a sewing machine, you should pay attention to the noise of the engine and the smooth running of the working foot. Expensive models are distinguished by low noise level, easy running and smooth adjustment of operating modes.
The correct operation of the device depends on the correct settings – setting the width and length of the stitch, adjusting the presser foot pressure, proper selection of threads and working needles.
The standard equipment for different models of sewing equipment includes the following tools: screwdrivers (large, small), cleaning brush, tweezers, a set of needles, a net for spools of thread, a spool holder and a looper.
When choosing a cover stitcher, all performance features are important, but the key ones are the width and length of the stitch, the ergonomics of the controls and the quietness of the operating motor.
If you need to perform several types of flat seams, then it is better to give preference to three-needle models. Sewing equipment is located on a separate work surface, so it is recommended to purchase a functional table for it.
Advertising from sponsors: //