How to adjust the tension on your sewing machine
Adjust Sewing Machine's Tension
Following up on my first hub "Undocumented tips on how to set your serger/overlocker's tension", I have dotted down a few tips that does not usually get mentioned in a manual or not in such detail.
The first thing I look at, is if the machine is threaded properly and sometimes, just by re-threading the machine, helps. But if that fails to solve the problem here are a few more tips.
If the problem is stitches that are not interlocking in the middle of the material - the bottom thread is visible on top or the top thread is visible at the bottom - it is either because the needle thread could be too loose or too tight and the same applies for the bobbin thread.
The normal setting for the tension of the needle thread is generally between 3 and 5 on the tension wheel/knob. (Fig 1) The higher the number, the tighter the tension and the other way around. If the needle thread is pulling through to the bottom, you need to tighten the tension and if the bobbin thread is pulling through to the top you need to loosen the tension.
If the tension knob/wheel does not make a difference, check the bobbin case's tension. The correct tension for the bobbin case is, when you hold the bobbin-case in your one hand and with your other hand make a brief, sharp upward movement, the bobbin must gradually slip downwards. (Fig. 2) If it is sliding down too fast, tighten the tension screw and if it is not sliding at all or having trouble sliding, loosen the tension screw. When tightening or loosening the screw, do it 1 or 2 millimeters at a time. (Fig. 3)
If none of the above mentioned works, check if there is no loose threads or wool (material dust) lodged between the tension-plate of the bobbin-case and the bobbin-case. If not, check between the tension blades through which the needle thread goes. I would also advise you to clean between the top tension-blades on a regular basis to get rid of the wax build-up or "wool" caused by the thread. To do that, take a sturdy, folded piece of cloth, push it in between the two blades and rub it up and down.
If you are still having problems, try changing the needles. Use thin needles for fine materials and thicker needles for thick materials.
NOTE: If you use a thin needle for example to sew chiffon and you loosen the needle tension to about 11/2 - 2 on the tension wheel/knob, it should prevent the material from puckering.
If your machine is skipping stitches, it is because the the machine's timing is out or the needle is not lodged deep enough into the needle casing. If adjusting the needle doesn't help then it is most likely the timing. You will have to then take it to the dealer or someone that fixes machines, to adjust the timing for you. It is usually then a good time to have the machine serviced as well.
It is a good idea to clean your machine on a regular basis, especially the bottom part. To do this I prefer to use a paintbrush of about 2.5cm (1inch) wide. It cleans quite effectively. When cleaning you could also loosen the feeder plate (Fig. 4) to clean between the feeders. Some just click off but with others you will have to screw out the screws. If you are like me, it is a good idea to put the screws in a "safe place" so that you won't lose them and it helps to remember where that "safe place" is.
Another thing that can also have an effect on the tension, is when the thread wasn't wind onto the bobbin properly. It was either wind on too loose or too tight.
I hope these tips will be helpful.... I sold two perfectly good machines because of, what I thought was i-repairable tension problems, before I knew these smaller details.
- How to adjust your serger/ovelocker's tension
A few tips on how to adjust your serger/overlocker's tension that's normally not mentioned in your machine's manual.