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1661 Botelho Drive, Ste 180
Walnut Creek, CA 94596

Open Tuesday - Saturday 9-5
Questions? 925-937-7575

Automatic Thread Delivery


Automatic Thread Delivery:
The Most Underrated Technology in Sewing
The goal of this email is to help you better understand the magic that is Baby Lock's Automatic Thread Delivery (ATD) System. In order to make a stitch, Baby Lock Sergers use ATD instead of traditional tension systems. To best understand ATD, it is important to first understand traditional tension systems and other basics of sewing machine engineering.
The Basics
Traditional home sewing machines tie knots with 2 threads-- the top thread and the bobbin thread. On the other hand, sergers generally use 3 to 5 threads to tie a knot that is more complicated than that of a home sewing machine.
Think about the knot you tie when you tie your shoes-- you must cinch the knot firm by pulling the two laces tightly. If you don't cinch it firm, the knot will not hold. The same principle applies to sewing machines-- to successfully make a stitch, the machine must cinch the knot firm. How does your machine cinch the knot? Through the machine's tension assembly.
Pictured above is an image of a home sewing machine's tension assembly. Traditional sergers (without ADT) also use a similar tension assembly. As you can see, the pictured tension assembly contains two metal discs.
When you thread the top half of the machine (with the presser foot in the raised position, of course), those discs separate and the thread slides between the discs. When you are ready to sew, you lower the presser foot onto the fabric and discs close together around the thread. As the machine sews, the thread is constantly pulled through the closed discs. The closed discs apply constant tension on the thread, which helps cinch the knot on each stitch.
As many already know, you are able to adjust your tension. On a home sewing machine with two threads, you might adjust the tension depending on where the knot is sitting in the fabric. In a perfect world, the knot sits right in the middle of the fabric. However, the knot might start poking up on either the bottom or topside of the fabric. If the knot is coming up to the top, then we loosen the tension. If it is poking down through the bottom, then we tighten the tension. That is the general rule.
Traditional Sergers
What about sergers? Although traditional sergers use a similar tension system as home sewing machines, adjusting the tension is not as simple. Because sergers use 3-5 threads instead of 2, the knot they stitch is more complicated. If the tension is unbalanced, balancing it is not as simple as readjusting for the knot poking out of the fabric.
When tension is off on a serger, the stitch looks ugly and it is not clear why. Often you will be using 4 threads, which means 4 sets of tension discs. If your stitch is off, which tension disc do you adjust? The left needle or the right needle? The upper looper or the lower looper? Do you need to tighten it or loosen it?
Serger tension is notoriously difficult to balance. The tiniest external factors can throw it off, such as switching to a different colored thread that is more heavily dyed (for example, tension will naturally increase when you switch from white thread to black thread). Until the invention Automatic Thread Delivery, balancing serging tension would require tinkering with the different tension dials. This could easily result in at least 30 minutes of troubleshooting. Your tension is off? Adjust 1 or 2 of the tension dials and sew. Did that not work? Adjust the other 2 and try again. Does it look worse than it did before? With a traditional serger, you will have to accept that achieving perfect tension will require lots of trial and error.
Automatic Thread Delivery
Baby Lock's Automatic Thread Delivery puts an end to all that tinkering and trial and error. Rather than putting tension on the thread itself, ATD delivers the required length of thread to form a balanced stitch. This is achieved by an internal mechanism of the machine-- sliding metal plates that determine the length of the thread delivered into the stitch. Machines with ATD work in a manner that is binary-- thread is either being delivered, or it is not being delivered. There is no tension. Therefore there is no tension adjustment-- no tinkering, no repeated trial and error. And, on top of all that, ADT is a purely mechanical feature. No computers are involved whatsoever.
Automatic Thread Delivery System lays the thread on the fabric as each stitch is formed. The fabric is not responsible for pulling the threads through the tension discs as on other overlockers. That means there is no stress placed on the fabric, allowing it to flow under the foot without being stretched or damaged. This allows you to sew from delicate tissue or silk chiffon through to lycra and layers of denim or fleecy without having to make any adjustments to the machine settings. Furthermore, the machine does not care what kind of thread you use-- you can switch from white thread to black thread seamlessly, as well as switching between Maxilock (which we sell) as well as Surelock (which we do not sell). Because there is no tension, the machine does not "feel" the thread like other sergers. No matter what you use, a perfect stitch is delivered every time.
In Conclusion
History tends to repeat itself, and I have noticed a pattern when it comes to the history of Baby Lock sergers. Time and time again, Baby Lock is at the forefront of innovation, and the rest of the sewing machine industry is forced to play catch-up. Then, without fail, Baby Lock will innovate again, and the rest of the industry must catch up again. This happened at the genesis of the company, when Baby Lock created the first "baby" overlock machine for home use. It happened again when they invented air-jet threading. It has now happened yet again, with the invention of thread release. The difference with thread release is that baby Lock still has a patent onthe technology, so the rest of the sewing machine industry cannot catch up. To this day, Baby Lock is the only manufacturer who has Auto Thread Delivery, the most underrated technology in sewing.
Below are a few Baby Lock Sergers and Coverstitch Combination Machines that are designed with Automatic Thread Delivery:
Call (925)-937-7575 for more information.
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Tuesday-Saturday
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