Friday, 17 July 2009

Passing The Sewing Machine Driving Test! Lesson 4

Sorry it's been so long coming! For those of you who have been following and have your machine threaded and ready to go, tension is something you need to understand.

For perfect tension on the top and bottom thread, you are aiming for the two threads to join exactly in the centre of your fabric or card. The bottom thread should not be visible on the top layer and equally, the top thread should not be visible on the bottom layer. If you achieve this you have perfect tension. Due to the thickness of threads, sometimes the tension needs altering. (Sometimes we want to alter it on purpose too - to get special effects - more about that in a later lesson.) Also, sometimes the tension alters with wear, as screws loosen off with the vibration of the machine. Checking three main things can sort out most stitching problems, tension is probably one of the main causes of problems.
The top tension is easy to adjust as there is usually some kind of dial or wheel with numbers on, with an indicator of where the mid point is. The bigger the number, the tighter the tension, usually. If the top tension is too loose, you will see loops of the top thread appearing on the back of the fabric and the bottom thread will be laid on the lower layer in a straight line, as in this diagram.

Working out if its your top tension too loose or your bottom tension is too tight is easy - check both!!
If the lower tension is too loose then loops of the lower thread will appear on the top surface of the fabric, where the top thread will be laid on the surface in a straight line.
To adjust the bottom tension you need the tiny screwdriver that comes with the sewing machine, as it is all controlled by a small screw on the spool case. Usually turning clockwise tightens the tension and turning anti clockwise loosens it.How do you know when it is just right? I'll tell you! Place the spool inside the spoolcase and pull the thread under the little spring until it clicks, as shown in a previous lesson. Now hold the whole assembly by the thread as in this diagram.
If the spool and spoolcase go flying down to the ground by gravity, (Like a yo-yo) the tension is too loose. Perfect tension should only allow the spool to move if the assembly is given a little shake and it descends a short distance. So, if you shake it and it does not move at all, you know your tension is too tight and it needs loosening. Simples!!!!
Right, off you go and check. Start by stitching a simple row of stitches and checking if they look the same from the top and underneath. Check it out! If they don't see whether the top thread is showing underneath or the bottom thread is showing on the top surface and adjust it yourself! let me know how you get on! Once you master tension, we can do some great tricks with it too! I promise to let you in on some secrets at a future date! TFLx


jackie(worcs) said...

Hello CC, thank you for the new lesson. My machine doesnt have a spool case. I just slot the bobbin in the area under the foot. Do you know how I would alter the tension on it? Im not going to meddle with it at the moment as it seems ok.
Love Jackie :-)

Crafty Dawn said...

I need one of these (plate to measure seems)when i bought my machine it didn't have one of these! shock horror! (it has a plte but NO measurements) so if I want to start sewing again seriously I need one.

Now I bought my machine a few yrs ago from Tesco I was seriously flabbergasted when I saw it didn't have one. I have made a dress and a few things cusions & so forth I really struggle with seems because of this. I have tried to look my modle up on the internet with no success (only £70 from Tesco but it is a little belter!) it's just this plate I need.

Love Dawnxx

Enjoy Italy you lucky thing, I look fwd to seeing what you pick up on your travels. I love what you bring back from France, buttons 'n' stuff

Gemma said...

Great tutorial re:using a sewing machine :D I'm now a follower
Gem x