Sewing Machine Bobbin Case

Sewing machine bobbin case

Bobbin case is an important part ofany sewing machine. If your sewing machine keeps breaking (top or bobbin) threads, has bobbin thread bunching, looping and tangling you need check a bobbin case first.
In this tutorial you find a description of bobbin case and a few tips that help you troubleshoot most problems.

Device of bobbin case

Firstly, let's learn a device of bobbin case.

Thread Tensioner of Your Sewing Machine. How to Adjust Thread Tension on Front Load Bobbin Case.

Two types of bobbin cases

Bobbin case of rotary hook system

The are most common two kinds of bobbin cases. There are which have a "finger" and there are bobbin cases without such 'finger'. It depends on type of shuttle hook system.
Read more about shuttle hook types in articles: Vertical oscillating shuttle hook and Vertical rotary shuttle hook.

Plastic or menal spools ?

Plastic bobbin

Tips: Use plastic bobbin only. Such spool is lighter and it will better slide inside bobbin case.

How to thread a bobbin

Holes on bobbin sides

Do you know for what is needed the holes on both sides of bobbin? On this photo is shown their purpose.

Thread tension adjusting

Thread tension spring

Any bobbin case has a thread tension spring. Adjusting of bobbin thread tension is done with turning this small screw under spring.

Screw on bobbin case

Be careful, do not turn out the screw more than one turn. It is easy to lose and almost impossible to replace with another.

Two types of bobbin cases

On this photo you see two different types of bobbin cases. Try find three main differences.
Bobbin case on right side is designed for industrial sewing machines.

Making a liner from plastic file

Making a liner from plastic file

Now I offer you my own trick that helps you adjust a bobbin thread tension correctly.
Note: This advice is best suited for mechanical old models of sewing machines, like Singer, etc.

Rounding a spool contour

Cut a little piece from hard plastic file and place a spool on it.
Outline rounded contour of bobbin with pencil.

How to cut a plastic liner

Now you need to cut around the contour circle.

Plastic liner on bottom a bobbin case

I forgot to explain for what we do it. Dirty and rusty inner metall surface of bobbin case will interfere with good sliding of bobbin. It's may be reason for emergence of many various problems connected with thread tension in stitch lines.
Such thin round plastic liner on bobbin case bottom provides more easily sliding of metal spool.

How to make inner hole of gasket

Inner hole of plastic gasket

For trimming this inner hole of plastic gasket will be better to use small manicure scissors.

How to insert the gasket into bobbin case

Now you need to insert the gasket into bobbin case.

How to trim outer edges of gasket

If it's size is too large you need trim outer (and inner) edges of plastic gasket.

Bobbin case cleaning

Bobbin case cleaning and oiling

Everyone knows that a sewing machine is needed periodically lubrication. But not everyone knows that a bobbin case should be cleaned periodically and oiling also.
Note: Outer metall surface of bobbin case must be ideally clean and shiny as a mirror.
To oiling any small joints of sewing machine is very convenient to use an usual medical syringe.

Oiling bobbin case

Before cleaning and oiling a bobbin case, insert small screwdriver under bobbin case latch, as shown.

Sewing machines oil

Add a few drops of sewing machines oil into slots of bobbin case latch.

How to adjust a bobbin thread tension

How to adjust a bobbin thread tension

Now you get last tip. I will teach you how can quickly and easily to adjust tension a thread going from bobbin case.
Insert a spool into bobbin case. Pass the thread under spring through the thread slot. Pull out the thread about 30-40 cm.
Hold this thread with fingers and lift the bobbin case. Now you need pull the thread sharply up when bobbin case is in hanging position. Thread should come out only a few centimeters.

Problems Thread Tension of Sewing Machines
Problems Thread Tension of Sewing Machines

If you have thread tension problems here you find tips how to fix many of them. Tips and tricks from professional sewing machines mechanic.

Vertical Rotary Shuttle Hook System
Vertical Rotary Shuttle Hook

Most of sewing machines middle and upper classes have rotary vertical or horizontal hook system. In this post you will learn how works a vertical rotary hook. Main features of this device and repair tips.

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Tips For Choosing a Sewing Machine

How to choose and buy your first sewing machine or upgrade your old model? Few key features of sewing machines you need to know necessarily.

Bobbin and Top Threads Problems
Sewing Machine Threads Problems

If your sewing machine keeps breaking thread this tutorial help you to fix these problems.

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How to Make an Inverted Pleat Skirt

If you will sew a skirt with pleats around, you need read this tutorial. These steps help you make inverted pleats correctly.

Rolled Hem Presser Foot Tutorial
Rolled Hem Presser Foot Tutorial

Using a rolled hem presser foot is simple way to hem thin fabrics. Tutorial has photos with pro comments.

My sewing patterns pdf
Patterns and Tutorials PDF