As a Nolting Longarm dealer, I have received many calls over the years for longarm help and advice. The calls can be broken down into two categories, (1) mechanical, such as broken needle, timing, or frame problem, and (2) stitch quality and quilting problems. Tension issues seem to top the list over all.
This may come as a surprise to you, but there are many situations where adjusting the
bobbin and top tension will NOT solve the problem. In other words, when there “seems” to be a tension issue, there can be one of a number of other reasons causing the tension to be unbalanced. When you find that adjusting the bobbin and/or top tension are not helping, then you need to look further to see what the real reason is for the poor tension. Here is a check list of some common issues that can cause poor tension. Some of these can be corrected by adjusting the bobbin or top tension, but for most of these, the problem must be corrected.
What is good tension versus poor tension. Good tension is when the top and bobbin
thread form the stitch in the middle creating a balanced stitch. When quilting, this is in the batting. Poor tension is defined as an unbalanced stitch with either the top thread or bottom thread laying on the fabric surface or railroading. Railroading is when the top thread is pulled below the backing or the bobbin thread is pulled through to the top of the quilt. Poor tension never looks good and can even be felt with the fingers. The flat line thread can be felt, and railroading feels bumpy. When the tension is balanced, both the top thread and bobbin thread will pull slightly into the batting giving the quilt texture. The fingers feel a slight indent in the backing and top and the thread feels smooth.
Tension Check List – What To Check To Correct Poor Tension
Poor quality batting. Regardless of what you pay for batting, if the batting is inconsistent in thickness, you are asking for problems. Batting that is inconsistent in thickness will be thick in places and very thin in places. In the thin areas of this type of batting, there simply is no place for the top and bottom thread to form a stitch. As a result, the stitch is pulled to either the top or bottom of the quilt.
To prove this point, I stitched a side by side sample using Quilter’s Dream select cotton
next to a poly (unknown brand) that varied in thickness from very puffy to so thin you could see your finger prints. I FMQed (free motion quilted) feathers and other designs across the sample without making any tension adjustments. Results: The tension was perfect on the Quilter’s Dream batting top and backing, but varied from acceptable to poor to unacceptable on the inconsistent thickness poly. In poor places the thread laid on the top of the fabric and in unacceptable places there was railroading (the top thread totally pulled to the bottom).
Purchasing the best quality, same consistent thickness batting is a small investment to make to assure quality stitching, a quality quilting job, and time spent without frustration trying to constantly make tension adjustments.
Needle. The machine needle is a very important part of a successful quilting equation as poor tension can result from a number of needle issues.
- Using the wrong type of needle. Have you experienced tension or inconsistent tension problems when quilting batik, especially when batik is on both the top and backing? We now recommend using a ballpoint needle when quilting batik fabric. Because most batik fabrics have a higher thread count, it is harder for the needle to pierce the fabric to deliver the top thread to the correct spot to make a balanced stitch. The ballpoint needle for longarm machines (different than the ballpoint for sewing knits on home machines), has a slightly rounded point that pushes the fibers apart making penetration better and placing the top thread correctly to make a stitch. Groz-Beckert makes a needle with a “light ball” point that is suitable for woven cotton fabrics. The Groz-Beckert ballpoint packages are labeled with
“FFG”, the needles are titanium coated, and are SAN 11. (these work with Nolting L and M hook machines) To avoid damage to your longarm, make sure the numbers match the needles required for your machine.
- Needle incorrectly inserted in the machine. For a perfect stitch to form, the hook point must pass behind the needle in the scarf (indentation) to pick up the top thread loop as the needle starts pulling up. If the needle is inserted backwards (will likely hear clicking), or turned slightly to the left or right, the thread loop will not be in the correct spot to be picked up by the hook, or will be picked up too soon, or too late, causing the tension problem.
- Dull needle or damaged needle. Needles do wear out. In fact, the point on them wears down much faster than you would think. I have often solved a tension problem by simply changing the needle. The reason is that a dull needle has trouble penetrating the fabric resulting in a delay in delivering the top thread at the optimum time for a balanced stitch. Always change the needle every 8 hours of quilting. Remember, too, that even a new needle might be defective. If you are experiencing problems, replace the needle.
- Needle too small for thread. A needle that is too small for the thread being used does not have a deep enough groove on the front of the needle to carry the thread through the quilt sandwich. As a result, there is a delay, or even non delivery of enough thread to make the loop. When the thread loop is not picked up at the right moment, the thread tension will not look right. It is always better to over size the needle rather than undersize the needle. Yes, the slightly larger needle will leave a little larger hole, but the holes will close up. The higher the number on the package, the larger the needle and the larger (wider and deeper) the groove.
Top thread caught. If “all of a sudden” there is a change to terrible tension, look for a problem with the thread path or thread delivery from the bobbin. Once in awhile the top thread will spin off the cone so fast that a loop of it will get caught some place. Recently this happened to me. When the tension changed and the bobbin thread was visible on the top, I started tweaking the top tension, but the tension problem did not go away. When I checked the thread path I found the top thread looped around the three-hole thread guide above the tension assembly. Rule of thumb, always look for something obvious when tension changes “all of a sudden.”
Quilt sandwich too tight on the frame. Remember that the machine is constantly moving in different directions as you quilt. It does not stop moving as each stitch is made. As a result, the needle will flex as it is going up and down through the quilt sandwich. If the quilt is loaded too tight on the frame, there is more needle flex displacing the position of the top thread loop, often causing what appears to be a tension problem. Loosen the quilt roller on the frame one or two cogs. You should be able to see the throat of the machine moving under the quilt.
Quilting too fast. Just because we can make our longarm machines go fast doesn’t mean we should. Do you rush your brownies baking in the oven 10 minutes instead of 25? It takes time for the brownies to bake to the right doneness. The same is true for quilting. The faster you go, the more needle flex and the more likely there will be what looks like tension problems. Slow down and enjoy the journey.
Thread quality. Poor quality thread and thread not designed for machine quilting can be weak, inconsistent in thickness, have slubs, or even be knotted part way through the cone. Using poor quality thread or thread not meant for machine quilting could result in thread breakage which can cause broken needles, scratches to the hook and pricks in or around the needle hole from a broken needle, and could even knock the machine out of timing. This is in addition to the thread not performing causing what looks like a tension problem. Always select thread that is labeled for machine or longarm quilting. These threads are designed with extra strength for the rigors of machine movement as well as running through the machine and stitching three layers together.
Type of batting and thread. Battings and threads are made from different types of fibers. Some battings and threads are more abrasive than others. This wears on the needle eye and point and can result in needle penetration problems and poor stitch quality. Realize that every quilt is a different set of variables. With each quilt project, start fresh with a new needle sized for the thread being used. Sometimes a particular thread will be more difficult to use with some battings, causing the thread to “drag” creating tension problems. If the particular thread combination (top and bobbin) is not working with the quilt sandwich, try a different thread.
The weather. Do you have more tension problems quilting in the summer than during the winter? It could be the humidity. Cotton can absorb up to 40% its weight in moisture, right from the air. The quilt top and backing is usually cotton, the batting is often cotton, as wellas the thread. As the temperature outside and inside goes up, the air can hold more moisture and the relative humidity goes up. The science principle of substances moving from where there is more to less holds true here. The moisture in the higher moisture air moves to the lower moisture cotton fabric, batting and thread. As the cotton absorbs moisture, the fibers swell. Thread may not flow as easily through the machine or needle eye and the fabric and batting may resist the stitching, all of which may cause what looks like tension problems.
Solution: Keep batting in the package until ready to use. Fluff it up in the dryer on no heat. Run a dehumidifier, especially if your studio is in a basement, or run the air conditioning which typically removes moisture from the air. If you had no problems yesterday and today everything is the same with the same quilt and same thread, but the tension is terrible, run the dehumidifier or air conditioner, wait a day or two, then try again. When the humidity goes back down, everything will work better. I have experienced this problem as have other quilters. If you are feeling uncomfortable from the humidity, your quilt is, too.
Tension problems can be very frustrating. Even becoming comfortable adjusting the bobbin and top tension can take time. It is important to realize that there are many factors that can affect the creation of the perfect balanced stitch. The next time you run into a tension problem and adjusting the bobbin or top tension doesn’t work, take time to go through this list and analyze what might be causing the problem.