Tip & How-To about Sewing Machines

Setting Sewing Machine Tensions

When you sew you want a nice sturdy seam, one that won't pull apart or leave gaps or cause puckering. To get this it's important to have the tensions set correctly. Many seamstresses get confused about how to set their tension. It's a fairly simple process once you understand a few basic things.

BASIC LAW OF TENSION to form the stitch: The UPPER thread tension changes the look on the UNDERSIDE of a seam while the BOBBIN tension, the bottom tension effects the appearance of the TOP SIDE of the seam. That is quite opposite of what most people think. Basically what you want is for the top and bobbin tensions to equal so that the stitch forms half way between the two.

If you can see threads from the bottom side of the stitch showing on the TOP side of the seam, like the graphic below, then either the BOBBIN tension is too loose or the TOP tension is too tight.

If there are loops on the bottom side of the seam, like the illustration below, then the TOP thread tension is too loose, or the BOBBIN tension is too tight. Typically the TOP tension is too loose.

If there is puckering on the top side then most likely the TOP tension is too tight, though it may also be the the BOBBIN tension is way too loose.

So how can we tell which it is? The best way its to begin by taking a scrap piece of the fabric you will be sewing on, or at least the same type of fabric, picking the widest zigzag stitch possible with a medium to long length of stitch and sew several inches. Now examine the seam remembering which is the top and which is the bottom. If it does not look identical on both sides then one of the tension settings is wrong. (it is also possible that the needle is the wrong type but for the moment let's assume it's the tension).

If there's a problem with the stitch you can use the above rules to figure out which tension is off. However, as the top and bottom tensions work together let's begin by going through a basic check-off list.

First examine the threading of the upper thread and make sure it is correctly following the path and isn't catching on something. This is really important when you think you've looked through everything and just can't 'see' the problem. Taking the time to go through these steps can save you a lot of pulled hair!

Next pull out the bobbin and examine it in it's case. Are the threads would around it evenly or are they all jumbled and crisscrossed? Jumbled up is a BAD thing. Try a different bobbin that is wound correctly. Now examine if the thread is coming out of the proper place, through the tension slot. Pull on the thread to see if there's total resistant. If so, something isn't right. But it can also be a problem if there is no resistance so let's now do this test.

Suspend the bobbin in it's case by the thread. Let it dangle there is space, still holding it by the thread as if it was a yoyo. It should dangle there with a little slipping, the length of thread between it and your fingers getting a bit longer. If it hits the floor there's no resistance! You have NO tension. That is BAD. Now, while still dangling it gently flick your wrist like you're holding a yoyo and wanting it to drop down a little bit, which is exactly what it should do if the tension is correct. If it doesn't release any thread at all, doesn't drop down a bit then the tension is too tight. Most bobbin tensions are adjusted by turning the little screw on the casing next to where the thread comes out. (Make sure that the bobbin turns in the case the right direction too which is the same direction of the slot!)

If the bobbin drops a lot it is too loose and you will need to tighten it a bit. Remember that a gentle flick should allow more thread to come out but not reel out. There should be some resistance.

Now that we have the bobbin correctly adjusted place it back in the machine and sew another test seam and examine it. By using the rules at the beginning of this tip determine if the upper tension is just right, too loose or too tight. Adjust the upper thread tension accordingly, first raising the pressure foot then turning the dial or however your machine adjusts tension. The higher the number the tighter the tension and vice-versa.

So that you know what the upper tension should feel like pull on the thread at a point BEFORE it goes through the needle first. Pulling after it goes through the needle puts a bit more tension on the thread and I want you to feel the tension before that point. If the tension is too tight and you pull on it after it goes through the needle it may break the needle if it's a small sized needle. You should feel some resistance. You shouldn't have to tug hard on it to pull more thread through but it also shouldn't reel out without any resistance. If the thread is breaking either the tension is very high or the thread is catching somewhere. Check the threading as well as look to see if the spool is turning freely on the spindle. Sometimes the thread will catch on the spool itself. When you buy a new spool of thread remember how the end was through a tiny slot on the side of one end? If that slot is on the bottom of the spool on the spindle it can sometimes catch the thread as it turns. Simply turn the spool upside down and re-thread the machine if needed.

Now once more do a test seam and examine it. Follow the above steps until the top and bottom of the zigzag are identical - perfect!

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ZIGZAG STITCH PUCKERS MATERIAL


Most sewing machines will cause puckering when zig-zaging, especially when sewing light-weight fabric like chiffon, etc. Try a brand new needle. You can try narrowing the zig-zag so there is not such a large gap between the left & right swing. Can also try loosening the tension a bit so the thread is not pulling so tightly. Another possibility (if your machine has the capability) is to increase the presser foot pressure so there is more pressure applied between the presser foot and the feed dogs. Or, try using a layer of wash-away stabilizer or clean (unused) newsprint paper with the fabric to help give it some stability.

How to Adjust Sewing Machine Tension on Craftsy

How to Prevent Your Sewing Machine from Puckering Fabric Howcast

https://groups.google.com/forum/#!topic/alt.sewing/AOhNY36JOa0

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May 22, 2016 | Sewing Machines

1 Answer

My seams are puckering. I have a Brother sewing machine. What am I doing wrong?


Puckered seams are usually caused by incorrect tension. But first check to make sure your bobbin is inserted correctly and that there is a good tight wind on the bobbin itself. Then, check the tension disks in the upper threading and make sure there is no stray thread lodged in there. Next, check the upper threading to be sure you have the thread going correctly through each of the thread guides and between the tension disks/plates. Finally, check the tension. Generally it should be on 3 but each machine has different symbols for the tension. My Brother product uses a 3 tension. I've been sewing for over 50 years and I still occasionally have pucker problems. It's usually because there's a small stray piece of thread in between the tension disks. I hope this helps you. If it does, please come back to Fixya and rate my information! Thanks.

Aug 02, 2011 | Sewing Machines

1 Answer

My singer cg 590 c puckers when I zigzag and sometimes when I sew straight seams


a wide zig-zag on a light weight fabric single layer is almost guaranteed to pucker up, just because the thread is under tension and this is often stronger than the fabric being pulled together by the stitches.

However, if a straight seam is puckering, this could be caused by a blunt needle, too big needle, or too tight tension or too long stitch length. You should be able to vary some of these variables to reduce the puckering and improve the stitch appearance. Other things to check might be the top thread being caught up somewhere in the thread path and pulling on the stitching.

If I am finishing the cut edge of aa single layer of light weight fabric I would use a three step zigzag to hold the fabric firmly and neatly.

Hope this helps a little?

Mar 29, 2011 | Sewing Machines

1 Answer

what tension should I use for fine materials? I have a Toyota RA41


The proper tension is a tension that locks the threads together tightly (you don't see a gap in your seem when you pull the two separate fabric pieces apart after sewing). But the biggest problem I see is when people have the thread tension so tight that it puckers the fabric as it's sewn. Thread tension is a balancing act between three forces top tension, bobbin tension, and fabric

Hope this helps...
Chris
glfi.com

Jan 20, 2011 | Toyota 803508 Sewing Machine

1 Answer

My white speedylock 1600 is being difficult.. The top threads lay and look perfect.. but the bottom threads are loose.. What can I do about this?


This machine has differential feed (top tension is different from bottom and fabric feed rate can be different from bottom). turn the dials for tension and feed rates to adjust. Adjust bottom tension to tighten bottom threads and possibly speed up bottom feed rate. Tough to say without more info.

Good luck and please rate me.

From White Sewing web site.

"Are wavy fabrics making you seasick? Do puckers leave a sour taste in your mouth? Then you need differential feed. It eliminates distortion and wavy seams when serging knits, plus it prevents puckers and pulled seams on lightweight fabrics. Turn the dial again for instant gathers.

Nov 23, 2009 | White Sewing Speedylock 1600 Mechanical...

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