juliasb

Normally my rule of thumb is Don't Touch The Tension! However when the tension is off on a machine I always forget how to do a proper adjustment. I know the upper tension is most frequently the problem but not always. On one of the older machines I have here it has a nice looking stitch coming down with no loops. The problem seems to be in the bottom which appears to be just a straight line of thread. I know this too could be upper tension.
I know this is most likely a very repetitive question here but how do you know which needs adjusting and how do you know if is to tight or to loose? I sure would like to try my hand at fixing this myself. I know there is a world of knowledge here on this subject. Thanks

patricej

if the top thread is looping on the bottom, or if the bottom thread "just lays there" as you described, then you need to adjust the top tension.

if the reverse is true, the tension problem is on the bottom.
don't fiddle with the bobbin case tension unless the problem occurs all the time.

many times, when the tension seems to be off on the bottom, the real culprit is either needle size, or incompatible threads in top and bottom. (e.g. top thread is heavy weight or stiff, bottom is light. the bottom thread might not pull the top to the back.)

bkay

You said older machine, so I'm assuming it's all manual. Put different colored threads in the bobbin and on top. Sew a three or four inch line of stitches on some kind of fabric you usually use and the number of layers that are your usual (or whatever is giving you problem) and look at it. If your bottom thread is showing on the top, you need to loosen the top tension. If the top thread is showing on the bottom, you need to tighten the top tension. Rarely, you may need to adjust the bobbin tension. Generally speaking, you need a tiny screwdriver and the instructions from your manual to do that (make tiny, tiny adjustments on the bobbin and test, then adjust again and test). There is generally a screw that gets tightened or loosened. It's not hard to do. Optimally, you want the the tensions to be perfectly balanced so that you see the same amount of thread on each side. Usually, you can do it by adjusting the top tension only, though.

It wouldn't hurt to clean the tension disks before you start the process. You just take something like dental floss, pipe cleaners or something and run it between the disks.

There are some great tutorials on here on adjusting tension. Do a search and you'll find many. Refresh the page after you open it, or it will appear blank.

If you don't have a manual for your machine, you can download one of the free ones at ISMACS.net. The process will be slightly different if you have a drop in bobbin or a removable bobbin case.

I have to change the tension on my vintage machine when I use a walking foot and with different threads. I find that I really have to loosen the top tension when I use clear thread.

Oh, and the bottom is just a straight line of thread. The top thread loops around the bottom thread to give you a stitch.

bkay

Tartan

​First, take a picture of your tension settings. You can always set it back to where it was if the adjustments make it worse.

Jingle

Not long ago to get a great looking stitch I had to slightly loosen the bobbin tension. Seems after 8 - 10 of sewing it tightened slightly. Stitches now look great.

juliasb

Now, I have tried all these things and nothing is making a single change not for better or worse. What next the repair shop?

Barb in Louisiana

Is your thread going through the tension assembly correctly?

bkay

You are not too clear on what the problem is. Nor have you told us what kind of machine you have. What exactly is the problem?

You say the bottom is just a straight line of thread. It is just a straight line of thread. That is what it is. Nothing changes that. If you increase the top tension, it pulls the bottom (bobbin) thread up slightly toward the top fabric. At that point, it doesn't look like a straight line of thread, but that is all it is.

What are you trying to do that doesn't work? Are you saying you want to increase the tension on the top thread and it doesn't work?

If it's time to take the machine in for service, you need to have a problem. What is the problem?

Someone posted to one of the best threads on tension, which brought it up again. When I mentioned that there were great threads about tension, this is the one I thought about. I suggest you read it. If you don't find a solution to whatever problem you have, take the machine to the shop.

bkay

coopah

I had difficulty like yours. Just a straight line of thread and loops from the top. I didn't change any tension, but cleaned all around the bobbin, made sure the thread in the top and bottom were the same, reinserted the bobbin, rethreaded the top thread...that did it! I think I was probably using two different weights of thread. At a class by Nova Montgomery with my FW, I couldn't get the tension correct. Nova came and did something with the tension and it was a bit different for my machine than on most FWs. So if it can't be adjusted by all of the above hints/helps, it may be time for an expert on your machine.

Onebyone

I change tension when change thread type in bobbin or top. I set it to 0 and go up a notch until the stitches are balanced. This is how I learned to set tension in home ec class. We had the older machines but it works for any tension on any machine. Starting at 0 allows the tension discs to adjust correctly.