If you are experiencing problems with embroidery designs that don't sew out well and you want to find out why, then you need to go back to basics:
If you're not sure then try a stitch out using a good quality, non-stretch, woven fabric with a good quality medium weight cut-away backing. Make sure that both backing and fabric are caught in the hoop and are hooped tightly.
Tip: Don't cut a piece of backing and then slip it under the hoop after the garment has been hooped. The backing must be hopped with the fabric!
If that works well then try that same backing with your knitted garment / fabric - once again making sure that both are hooped tightly.
If that works then you might try using a lighter weight backing.
Using this process you will eventually find the reason for the low quality stitch-out.
Let's try and avoid problems like this!
Correctly adjusted bobbin thread tension should always be the first step in setting up the needle thread tension on ANY sewing or embroidery machine.
You must set the bobbin thread tension first and then adjust all of the needle thread tensions so that they are balanced with the bobbin.
If you are finding it difficult to set the bobbin tension then there are a number of possible reasons why :
A good, balanced bobbin thread tension should show up on the reverse side of the fabric as 1/3 needle thread, 1/3 bobbin thread and 1/3 bobbin thread. Ideally those three should show up 3 balanced and even columns.
Here are the most common problems with the bobbin thread tension:
Low quality bobbin thread with uneven winding and/or slubs
This will typically show up on the reverse side of the fabric as a very irregular change in the amount of bobbin thread that you can see. As the slubs pass under the bobbin tension spring, the tension suddenly increases and this will show up as a sudden narrowing of the column of bobbin thread. REPLACE THE THREAD
Damaged bobbin - may have been dropped and is bent
When a bent bobbin is used, what happens is that the bobbin touches the bobbin case once every revolution. This shows up as a very regular change in bobbin tension with an equal distance between the waves in the bobbin thread column. REPLACE THE BOBBIN
Damaged bobbin case - side is bent in catching on the bobbin
This may show up as similar to a bent bobbin but is likely to cause more changes and they may not be quite as regular and even. REPLACE THE BOBBIN CASE. The metal is very brittle - If you try to bend it it will most likely snap.
Lint or wax stuck under the tension spring making thread tension too loose
This problem would normally show up as too much bobbin thread on the reverse side of the fabric and possibly even bobbin thread pulling up to the top surface of the fabric. Tightening the bobbin tension screw will not necessarily help because the wax or lint under the spring prevents it from pressing down any more onto the thread. REMOVE THE SPRING AND CLEAN UNDER AWAY ANY WAX OR LINT. CHECK AND ADJUST THE TENSION.
Thread tension setting is really quite simple but unfortunately some machine manufacturers will tell you that it is TABOO to try and adjust the tensions yourself. They might even suggest that you will void your warranty. I say nonsense!
You know why? Because during manufacture, they set the bobbin tension perfectly to suit the bobbin thread that their own company sells, knowing very well that if you try another type of thread which is thicker or thinner then the tension will change.
If you have a small bobbin screw driver and a bobbin thread tension setting device then it is child's play to adjust the bobbin tension to suit your own thread.
Just take out the bobbin case with your current bobbin thread and put it into the tension setting device. Wind the thread around the tension pulley and gently pull out a few inches of thread. You will see the exact tension reading for your current thread as the tension needle moves up and down the readout scale. Take a note of the tension reading.
Now all you have to do is put your new bobbin thread into the bobbin case and carry out the same test.
If the tension is different to your original thread then adjust the tension spring on the bobbin case a little. Try a 1/4 turn of the tension screw in the anti-clockwise direction to loosen the tension and clock-wise to tighten the tension.
Now test with the tension gauge again. Try it! You'll be amazed at how easy it is to become a master of bobbin thread tension.