Crushing the lower thread into a tangle under the needle plate is a direct sign of desynchronization of work shuttle and the upper thread, arising from improper filling or wear of the parts of the mechanism. When the bottom thread in the old hand sewing machine gets confused, the needle often penetrates the fabric at the wrong moment, not having time to capture the loop, or the tension of the threads is selected so that the bottom one is simply pulled upwards by jerks. Owners of rare models singer, Podolsk or ZM They are faced with this most often after long downtime, when the lubricant thickened, and the springs of the regulators lost elasticity. Ignoring this symptom leads to a breakage of the needle, deformation of the tissue and the inability to perform even a simple connecting seam.
The first priority in the diagnosis is to check the state of the shuttle And its rotating nose, which should be perfectly smooth. Any barb on a metal surface creates resistance, which causes the thread to break or become entangled, forming a so-called "beard". Mechanical damage to the shuttle body requires its replacement, since polishing at home without special equipment rarely gives a long-term result. If the metal is intact, then the reason lies in a violation of the refueling algorithm or malfunctions in the work. transporter.
⚠️ Warning: Before starting any setup work, be sure to remove your foot and remove the needle to avoid injury and damage to the mechanism when the flywheel is rotating.
Diagnostics of the shuttle device condition
The foundation of a quality seam is the correct interaction of the upper and lower threads, and if the lower thread is confused, the inspection should begin with the node. shuttle. Older handheld machines most often use a horizontal swinging shuttle, which requires precise installation. When removing the needle plate and removing the shuttle, it is necessary to carefully examine it for corrosion, scorching from old lubrication or mechanical damage. Even microscopic roughness in the path of the thread can disrupt the uniformity of its supply.
It is important to check how it is inserted. squiggle In the cap. The thread should come out of the spools counterclockwise (for most models) and pass under the tension cap plate. If the thread just lies in the spools without fixing the tension spring, it will pop out with loops, creating chaotic knots on the back of the fabric. Adjusting the screw on the tension cap plate is a delicate process that requires the screwdriver to rotate literally a fraction of the turnover.
- 🔍 Check for the absence of pile and dust in the grooves of the shuttle shaft, as the compressed dirt changes the trajectory of the thread.
- 🔧 Make sure that the cap before clicking has stood in place in the shuttle shaft, otherwise the synchronization with the needle will be disrupted.
- 🧵 Inspect the thread itself: using cheap twisted threads on old machines often provokes them to fluff and get stuck.
Particular attention should be paid to the gap between the shuttle nose and the needle. Ideally, this gap is minimal, but the needle should not touch the metal of the shuttle. If a metal thud or grinding is heard when turning the flywheel, then the mechanism requires adjustment. On old cars. singer and Podolsk This is often solved by neat bending of the needle holder or adjusting the position of the shuttle shaft, but such work is better to entrust to the master if you are not confident in your abilities.
Rules for filling the top and bottom thread
The most common reason why the lower thread is confused is a banal violation of the refilling sequence of the upper thread. In old-style handheld machines, the path of the thread is strictly regulated by the design: it must pass through all thread leads, levers and, most importantly, get between the disks. tensioner. If the thread passes this knot or lies on top of it, and not inside, the tension will be absent, and from below an infinite tangle is formed.
The bottom thread filling also has its nuances. After the thread is passed through the spring plate of the cap, it must be stretched for 10-15 centimeters. When installing a shuttle in the machine, the tail of the thread must be held so that it does not go inside the mechanism. The first scrolling of the flywheel is done manually, without fabric, to make sure that the top thread has properly captured the bottom one and pulled it to the surface.
☑️ Filament filling checklist
The use of threads of different quality for the top and bottom of the seam is unacceptable on old mechanisms. If the upper thread is thick and strong, and the lower one is thin and weak, then when tightening the stitch, a thinner thread will break or form loops. Same threads - a pledge of stable suture. It is also worth checking whether the thread is twisted in the process of work; if the coil is not correct and the thread comes off it in jerks, this will inevitably lead to entanglement.
String adjustment of the thread assembly
The tension balance is the key parameter that determines whether the seam will be flat or the bottom thread will become confused. If the hinges of the lower thread are visible on the front side of the fabric, then the upper tension is too weak. Adjustment is made using a nut-regulator on the front panel of the machine. Turning clockwise increases tension, against - weakens. On old machines, the scale can be erased, so you need to act by the method of small steps, making test lines on the flap.
However, the problem may not be just in the upper regulator. The lower tensioner located on the shuttle cap also requires attention. If the tension screw on the cap is twisted too much, the thread will break; if weak, loops form from below. To check the correctness of the lower tension setting, there is a simple test: hang the tucked cap by the thread. If it slowly slides down under its own weight, the setting is correct. If it falls, the tension is weak, if it hangs in place, it is strong.
| Symptom of a seam defect | Probable cause | Action to eliminate |
|---|---|---|
| Lower strand hinges on top | Weak tension of the upper thread | Increase tension with the upper regulator |
| The top strand is visible from below. | Weak tension of the lower thread | Twisting the screw on the shuttle cap |
| The thread breaks when sewing | Excessive tension or burrs | Reduce tension, check the path of the thread |
| Stitches of different lengths | Problems with the transporter or foot | Check the pinching of the legs and teeth of the reiki |
Trying to adjust tension at random, without understanding the principle of operation thread-trapIt can lead to even more confusion. A nitro attractor is a metal arm with a hole that moves up and down; the thread must necessarily pass through its ear. If the thread has jumped off it, sewing is impossible.
The impact of needle quality and needle holder installation
Incorrectly selected or installed needle is the second most popular reason for confusion of the lower thread. In hand-held cars of the old sample, needles with a round or flattened head are used (depending on the model, for example, 122-123 for Singer. Installing the needle flat side in the wrong direction leads to the fact that the shuttle can not pick up the thread loop at the right time. As a result, the needle simply pierces the thread or slips past, leaving chaos from below.
A dull or curved needle also causes problems. When passing through the fabric, it can shift the material or tear the fibers of the thread, which provokes the formation of nodes. On old hand machines, the needle lifting mechanism can have a backlash, so it is important to insert the needle into the needle holder to the end and tightly clamping it with a screw. If the needle is high, the loop for the shuttle forms too late and the grip does not occur.
Table of matching needles for old machines
For Singer 16, 28, 128 models, needles with a round head and a long groove are used. For Podolsk machines 2M, 3M often suitable needles with a blade having one flat side. Always check the labeling on the needle pack for compatibility with your machine class.
The height of the needle installation is another critical parameter. In some models, the needle must be raised to the highest possible position for proper installation. If the needle is lowered too low, the shuttle's nose can hit it, blunt the tip, or break the needle, which will instantly cause the thread to become entangled around the needle holder. Before each needle replacement, it is recommended to wipe the needle from the oil and pile.
Maintenance and lubrication of the mechanism
Frozen lubrication and compressed fibrous garbage are the main enemies of old sewing machines. If the machine stood idle for a long time, the oil in the shuttle knot could turn into a thick substance that inhibits the rotation of the shuttle. This leads to the fact that the speed of movement of the thread does not coincide with the speed of rotation of the shaft, and the thread begins to wind on the nose. Before setting up, a complete cleaning and lubrication should be carried out.
Use only special sewing oil. The use of vegetable oils, WD-40 or motor oils is strictly prohibited: the first over time polymerize and glue together parts, the second - too liquid and quickly evaporate, without providing protection. The lubrication process involves dripping oil into all rubbing pairs: in the shuttle shaft, in the needle guide, in the axis of the levers. After lubrication, the machine must be idly spinned, putting a flap of fabric so that the oil is distributed.
⚠️ Warning: Never blow on the mouth to remove dust. The inhaled air contains moisture, which, when combined with metal dust, will cause parts to corrosion. Use only a soft brush or pear.
Cleaning the transporter's gear rack is also important. If a felt of thread is stuffed between the teeth, the fabric will move in jerks. Uneven progress of the fabric leads to the fact that the length of the stitch floats, and the thread does not have time to tighten, remaining hanging with loops from below. Cleaning is better to carry out an old toothbrush, carefully sweeping out garbage from hard-to-reach places.
Algorithm for eliminating seam defects
If the bottom thread gets confused, act systematically, eliminating the causes one after the other. You don’t need to turn all the regulators at once. Start by replacing the needle with a new and correct installation. Then completely refuel the machine again, observing the order of threading. If the problem has not gone away, check the tension of the threads. And only last resort to disassembling the shuttle knot for deep cleaning.
Often, a simple change in the type of thread helps. Older machines can be capricious to modern synthetic threads that slide and electrify. Try using quality cotton threads or special threads for old machines. It is also worth checking whether it has deformed itself. needle-plate. If the needle hole is broken or has burrs, the thread will cling to the edges and become entangled.
In cases where no settings help, perhaps the problem is the wear of the parts of the mechanism. The stretched spring mechanism of the nit-trap or the developed shuttle shaft require replacement. However, in 90% of cases, competent tension setting and cleaning bring the old hand machine back to life, allowing it to sew a smooth and beautiful line, like on the day of purchase.
The main secret of success: 80% of problems with entanglement of the bottom thread are solved by correctly installing the needle and refilling the top thread through a closed tension regulator.
Useful advice: Before you start sewing on an old typewriter, always make an "anchor" stitch. Put a double flap under your paw, lower the needle, turn the flywheel, stretch the lower thread up, wind both tails under your paw back and only then start twisting the handle. This will prevent the thread from being pulled into the shuttle in the first seconds of operation.
Why does the lower thread go out to the front side of the fabric with loops?
This is a classic sign of weak tension of the upper thread or too strong tension of the lower one. The top thread does not hold the bottom in the middle of the thickness of the fabric, and the bottom is pulled up. It is necessary to increase the tension of the upper regulator or loosen the screw on the shuttle cap.
Can I sew on an old machine without a nitrogen ruler on the rack?
No, you can't. Niten rulers (metal staples on the rack) set the correct trajectory and angle of the thread to the needle. Without them, the thread will go jerky, which will lead to constant entanglement and breakage.
How often should you lubricate a hand-held sewing machine?
When used actively, before each sewing session or after every 8-10 hours of work. If the machine is idle, lubrication is carried out before starting work, having previously removed the old thickened oil.
What if the thread is constantly torn in the area of the needle?
Check if the needle is too high or too low. Make sure the thread passes through the ear of the puller. Check the sharpness of the needle and the absence of burrs on the needle hole of the plate. The cause may also be too much tension.