Let’s talk about Thread Breaks!

A few weeks ago a customer called customer service because a design kept breaking thread in the same place time and time again. He was convinced there was a problem with how we digitized the design. In the wonderful world of embroidery thread breaks in the same place can indicate a problem with digitizing but digitizing is not always the case and a full review of what is going on is required to fully understand the problem. In this case the culprit turned out to be thread tension but in order to make that determination we had to examine numerous factors.

Digitizing: Poor digitizing can contribute to multiple thread breaks but in reality the digitizing has to be REALLY bad in order to cause thread breaks. Digitizing can play a role in multiple thread breaks but it is usually a contributing factor but not the cause. On multi-head machine it is easiest to determine if the problem is digitizing because it if it is, the thread break will occur on all of the heads in the same place at the same time or in very close proximity. On a single head machine this is much more difficult to determine. When a customer tells me they are having a multiple thread break problem with a design and they suspect digitizing my first question is always, “are you embroidering on a multi or single head machine.” Depending on the answer the conversation will go in different directions.

Is it really a thread break: This might sound like I am trying to “pass the buck” but I’m not. Many times what appears to be a thread break is not. Rather it is a “pull out” which will usually happen immediately after a thread trim or color change. Pull outs are mechanical in nature 99.99% of the time. Pull outs are usually caused because after a trim the tail on the bobbin thread is not long enough and the bobbin thread will not be able to tie a knot with the top thread causing the top thread to pull out from the eye of the needle. This is very easy to see. If you suspect this problem watch the thread path close to the take up lever on your machine as your machine trims. Right after the trim if the thread seems to “bounce” instead of going slack then taught as a stitch is forming then you are having a pull out. There are usually two ways to fix this. Most machines will have a software setting which will allow you to control the length of the bobbin tail after a trim. Short, medium and long are usually the choices. Try going up one level to solve the problem. If that does not fix the problem you will need to look at adjusting the “fork” that goes in and out by your bobbin case every time your machine makes a trim. This forks needs to briefly (and gently) come in contact with the bobbin at the time of a trim. If it doesn’t you need to adjust accordingly.
 

Mechanical: Thread breaks are notoriously mechanical in nature. Unfortunately almost everything that is not related to digitizing can fall under the mechanical umbrella but for the sake of this conversation I am going to limit mechanical causes (in order of ease to correct) to problems with condition of the needle, presser foot and throat plate, the thread path, needle depth machine timing and thread tensions.
 

Condition of needle, presser foot, hook and throat plate: As your machines forms stitches thread will come in to contact with several metal parts on your machine. If you are having problems with thread breaks you need to carefully examine the needle, presser foot hook and throat plate for any burrs. Use a magnifying class to do this. Even the smallest burr can and will cause thread breaks. Thread breaks that FRAY before a break are almost always caused by burrs on one of these metal parts. If a thread snaps cleanly it can still be a burr but it will usually be a bigger burr and much easier to see. In either case the remedy is the same. For needles, throw out the old and replace with new. For the other parts keep crocus cloth (an ultra-fine type of sand paper for buffing machine parts) and crocus cord in your shop to buff these parts smooth. If the burrs are really bad you might need to replace the part. You should always keep a supply of needles and at least one extra rotary hook in your shop at all times as well as a few presser feet and one or two extra throat plates.

Thread Path: Is your machine properly threaded? This might seem basic but I wish I had a dollar for every time I have seen an embroidery machine improperly threaded. I bet you I could have bought a very nice car by now. You might think I am exaggerating but I am not. One time I was called in to a shop to consult why a set of machines would not embroider as well as expected. There were a lot of problems with tensions and thread breaks. As it turned out 100% of the needles on more than one hundred heads, fifteen needles per embroidery head (1,500 needles baby) were incorrectly threaded.
I can’t tell you exactly how to thread your machine because all machines are different. However, I can tell you this. Your machine came with a manual that specifically describes how to thread the machine. You must follow this exactly. Your machine was engineered to strict standards. If you change the thread path (even a little bit) you have re-engineered the machine and that will almost always cause problems. Check your thread path!

Needle Depth: When your embroidery machine is at the bottom of its stroke your needle must be in a very specific position. Check your manual for this position and adjust your machine accordingly if required. Some manufactures will have you check needle depth when your needle is in the hook timing position. Either way the position is critical. You should become comfortable making this adjustment. However…and this is important. Before you make an adjustment make sure the needle is fully seated (all the way up) in the needle bar! I have mistimed an entire multi needle head because the needle I used to check needle depth was not properly installed in the needle bar. This is a frustrating and time consuming mistake to make!

Machine Timing: If you are having a lot of problems with thread breaks and you have checked your thread path and needle depth there is a good chance your hook timing is off. Your embroidery machine moves at very high speeds. The relationship between the rotary hook and the needle is of critical importance and must be properly maintained. Timing is easy to do but if not done incorrectly can cause big problems. If you are not mechanically inclined find a machine mechanic and have them check and adjust your timing as required and as part of a routine maintenance program. If you ever “crash” a needle in to a hoop you will for almost 100% certainty have to adjust your timing for the whole machine and the needle depth for the needle that crashed.

 

Tension: Last but certainly not least is the thread tension. For experienced operators adjusting tension is actually pretty easy but for newbies it can really be tricky and quite elusive. If your thread tension is not correct you can have all kinds of problems from poor quality to thread breaks and bird nesting that will completely destroy a garment in a fraction of a second.

Thread tension is the balance between your top thread and bobbin thread on your machine. These tensions must be roughly equal. You can run soft tensions (thread tension is on the lighter side of the scale) or firm tensions (tension on the tighter end of the scale) but either way your top and bottom must be close to the same.

There are several ways to test for this but before I go there let me say, “in my humble opinion it is always best to set the bobbin tension first and then adjust your top thread to the bobbin.”   To set the bobbin tension there are fancy tension gauges you can purchase but a simple test that does not require a tension gauge is this:

First – Make sure the bobbin is clean and there is no lint underneath the flat spring on the side of the bobbin case.

Second – Thread the bobbin as usual but do not put the thread through the pig tail on the top of the bobbin.

Third – pull out about 4 to 5inches of Bobbin thread.

Fourth – Dangle the bobbin, with the bobbin in the case.   The case should not freely release bobbin thread. It should stay put when you are holding the bobbin thread.

Fifth – Gently tug the bobbin thread like you are playing with a yo-yo. The bobbin case should drop a couple of inches and stop. If it goes all the way to the floor your tension is too loose. If it doesn’t drop at all or it just drops a teeny bit your tension is too tight. Adjust the “larger screw only” on the side of your bobbin case to adjust bobbin tension. If you cannot get the bobbin case to drop or prevent it from dropping to the floor replace the case with a new one. DO NOT try and replace the spring. Unless you are a glutton for punishment you are wasting your time.

After a while you will develop a feel for correct bobbin tension and will not need to do this test. But until then this is and free and good method for checking tension.

Once your bobbin tension is set you must adjust your top thread tension. You CANNOT check top tension on a needle unless the needle is in the sewing position. To check tension make sure your needle is in the sewing position and correctly threaded through the full path. With the thread through the eye of the needle pull the thread toward you in a straight line. The tension on the thread should “feel “ the same as on your bobbin. Adjust your tensioners accordingly to get the right feel. I can’t tell you which tensioners to adjust because all machines are different…and for better or worse you AMAYA guys don’t have top tensioners at all and this part of the discussion does not apply.

Once you have your top tension where you feel it is close you need to do an XOH test. What this means is you need to embroider a digitized pattern of a capital XOH programmed at about .50” tall and with 2mm column widths. Embroider this pattern on all heads and all needles. After you sew an XOH set take the pattern off of the machine and turn it upside down. Examine the embroidery. You should see two thirds top thread and one third bobbin thread. Unfortunately I cannot tell you which to adjust because what it really means is your tensions are not in balance. But from experience I can tell you the problem almost always starts in the bobbin. If you can get your bobbin set right then adjusting the top is usually pretty easy.

Bird Nesting is a “total failure” condition in thread tension and is easy to spot. Bird Nesting is apparent when it seems like your garment is trying to get sucked through the hole in your machines throat plate and underneath you will find a big gob of thread. I have had customer blame this on digitizing and while it might sound self-serving I can honestly tell you in 25 years I have never seen this to be caused by anything other than poor tension. And 99 times out of 100 it has been poor bobbin tension. There is virtually nothing a digitizer can do to cause bird nesting in a pattern. If you are getting bird nests check all of the basics. Start with your thread path to make sure your needle is threaded and then verify all tensions are properly adjusted. Pay particular attention to where thread passes between tension discs. Sometimes thread will pop out from between a disc and lose its tension.

One last thing on tension. Different color threads will have different tensions. Do not assume you can set and forget tension. While you want to avoid micro managing tension tension you can’t forget about it either. And finally…Different thread brands and different types of thread (polyester vs. rayon) will require different tensions settings. And if you go between 30, 40 and 60 weight threads you are really in for a treat and will need to know your stuff.  Even thread color can affect tension.  Black thread tensions differently than white.

Thread breaks can be excruciatingly frustrating to deal with. I know. I have been there, I have done that. No one on the planet understands better than me how annoying thread breaks can be. Nine out of ten times your thread break problems will be at the machine level.   But 10% of the time it will be the digitizing. When it is digitizing…you know Qdigitizing will do all we can to correct the issue for you. But I am here to tell you that if you take the time to properly maintain your machine, follow your thread paths correctly and keep your tensions properly adjusted you will reduce your thread breaks to a manageable level and produce extremely high quality embroidery.

As always – if you have any questions please do not hesitate to reach out to me here or feel free to call us during normal business hours on our toll free number, 877-733 -4390.