Sewing Machine Basics-The Lockstitch
Good Morning, Quilters!
It is important to understand how our sewing machines work in order to better understand how to troubleshoot when things go wrong.
For a better understanding of the lockstitch that our machines use – check out this short video.
What I’d like to point out is that the a large loop of top thread is pulled into the bobbin case for every small stitch. That means every point on a length of thread is pulled down into the case and back up again more than 100 times before it is laid down as a stitch. Thats a lot wear and tear on a strand of thread!
Consequently, if there is a burr anywhere in the thread path-(the stitch plate and the hook are the most common culprits) the thread is rubbed against that burr 100 times. It is easy to see how thread would shred and break!
Another place where the thread is vulnerable is against the inside of the eye of the needle. Think of that thread flossing against the needle eye more than 100 times. When a thread breaks and we replace the needle it is because of the eye of the needle. The eye gets worn and then damages the thread. (When we have skipped stitches–it is more likely the tip of the needle that is the problem.)
Today’s tips for Happy Quilting: Replace your needle frequently. Stitch with good thread. Keep your machine in good working order!
What about YOU?
Do YOU ever consider how YOUR machine works?
Do YOU take your machine for granted?
Do YOU take your machine to the “spa” regularly?
Do YOU change your needles frequently?
We’d LOVE to hear!
Your Carefree Quilter,
Lori
PS…All tutorials, images and information are the property of Lori Kennedy at The Inbox Jaunt and are intended for personal use only. Feel free to re-blog, pin or share with attribution to The Inbox Jaunt. For all other purposes, please contact me at lckennedy@hotmail.com. Thanks!
I clean my Bernina 710 and change the needle regularly. I have the machine serviced yearly.
I clean my machine fairly regularly, but always hope to do one more thing before I tackle that and then sometimes run into trouble. I’m really lucky as my husband has learned to repair sewing machines and can hear from his office when my machine is “thirsty” or needs a cleaning :-). He has also taught me many things about what to look for when thread breaks or tension is off. I’m getting quite fearless about turning bobbin case screws, oiling, looking for burrs, taking things apart….an easy process on the mechanical all metal machines! Practise does make perfect (not there yet, but on the road to it LOL).
Hi Lori. From looking at the video I now understand how it works. But I am not understanding your comment : That means every point on a length of thread is pulled down into the case and back up again more than 100 times before it is laid down as a stitch. You are not saying each stitch is a 100 times as that does mot make sense to me? Can you clarify?
I think….. this might make sense. Once the thread leaves the safety of the spool above, it gets tugged by the force/activity below.
For example, let’s imagine you made a tiny red dot on the thread that is immediately to the left of the spool, and watched that dot move down the path to the bobbin, and then into the fabric. Kind of interesting. Let’s try it.
I didn’t understand that point either and hope Lori will clarify it.
In order to form a stitch, the upper thread (yellow thread in the video) makes a loop that is pulled around the bobbin case by the hook mechanism. This loop pulls out far more upper thread than is needed to form the stitch. After the stitch is made, the take up lever pulls the extra upper thread (from that loop) back up. This is the part of the thread that goes in and out of the fabric & around the bobbin about 100 times before it is used to form a stitch. I hope that helps to clarify.
Good explanation Brenda.
I wondered the same thing. I don’t understand either.
Neat little video, but I also don’t understand the 100 times comment.
Good Morning Lori, Thanks for the reminder about watching out for burrs on the throat plate and the tip about the inside of needle eye being the culprit when our thread breaks. We are so blessed to have these wonderful machines and sometimes its the simple things that keep them going!
I sew or quilt almost every day on a Brother VQ3000 so I clean it at least once a week. And I get a little goofy (or perhaps anal) about changing needles. I keep a lot of them on hand so I’ll often do it in the middle of a large project to prevent a problem before it happens. I don’t throw out the needles right away; I save them and use them for smaller projects such as pot holders, placemats, bowl cozies that require less precision – then they’re thrown out.
Having sewn for most of my life, I’ve become experienced in carefully adjusting the tension screw on the bobbin case and I keep a jeweler’s loupe handy to check for burrs; my eyes aren’t what they used to be!
My machine “tells” me when it’s time for a tune-up, so that’s when I take it in for service.
Thanks for all your help and encouragement Lori!
My machine was recently skipping stitches. I changed needles, cleaned out the “fuzzies “ and then continued sewing . It was much improved!
I take my two Pfaffs in regularly. Love them so much the thought of replacing them fills me with dread. Problem free since 1994 and 2001 and I feel “at one” with my machines. I change needle at a minimum at the end of each hard day of sewing. I end my sewing session with a thorough cleaning and oiling before turning off the room lights – smiling in gratitude for another day of problem free stitching.
i have noticed that if fluff builds up in the bobbin case, then that too can contribute to thread breakage. So if a break happens I make sure that the bobbin area is clean.
I change my needle at the beginning of every project, in the middle if it’s a really big project, or if I am switching to a thread that needs a different size needle. I keep air cans to blow it out about every third time I sit down to quilt. If the bobbin case has to come out for any reason, it gets blown out. If I am changing needle plates, it gets blown out. (My VQ2400 has a bit of a lint phobia.) Easier to do those things often than to rip out the mess I get if I don’t do them.
You shouldn’t use air cans because they force lint farther into the machine and they add moisture that causes rust.
For more info, see https://weallsew.com/how-to-remove-lint-from-your-sewing-machine.
I had heard that, and didn’t use them for years. Then my Brother dealer told me it was perfectly OK to use them, and it is how their technician cleans machines.
I received “More Free Motion” this afternoon and love the book. Thank you for signing it and thank you for the enclosed gift—such a pleasant surprise that I will cherish ‼️‼️????
I had my Bernina 1130 cleaned and serviced a coupe weeks ago after a squeal developed! What they found was almost a whole spool of thread had come off from the thread spool and wrapped itself around the fly wheel! No wonder it let out a squeal! We need to have our machines cleaned once a year.