First, every sewing machine that I know of has a part in the bobbin case called an”anti-backlash spring”.  This part looks a little different in each brand, but its function is the same -  to stop backlash.

So what is backlash?  While sewing, the bobbin is spinning along, letting out thread.  Once you stop sewing, there is a good amount of energy built up in that spinning bobbin. If left to it’s own spin, the bobbin would continue to let out thread after the machine stopped sewing.  When you start up again, the machine must first use up the loose thread before jerking at the bobbin to cause it to spin again.  This whole issue is called backlash.  That can cause problems with stitch quality.

The “anti-backlash spring” creates a small amount of back pressure on the bobbin, which helps stop the bobbin from spinning after the machine stops sewing.  The slight friction created by the “anti-backlash spring” is critical to a proper operating bobbin case. This is the primary purpose of the spring.  In addition, the spring’s positive pressure helps even out the spin and maintains a constant bobbin tension, along with the bobbin case’s own tension spring/arm.

Now that I’ve explained that function, let’s examine what the Teflon washers do.  The instructions explain to remove the anti-backlash spring, and lay this washer into the case.  As many know, Teflon is a great material for preventing friction. (i.e. Teflon coated pans don’t stick.)  With the Teflon washers, we loose the important positive pressure, and slight friction, that prevents backlash and ensures a consistent tension.  In fact, these washers counteract everything that the anti-backlash springs were designed for.

In the 10+ years I have been working as a technician for longarm quilting machines, I have always been able to get a great stitch out of the “stock – factory issued” components.  Most add-ons are created to make someone money.  Now this isn’t for everything, occasionally someone truly finds an innovative product that improves the fundamental quality of an industry.  This is few and far between.

I say this, simply as a word of caution.  I am a geek… and therefore love to find gadgets and hack into existing systems to find new and inventive ways to use things.  Yet, I am also careful not to invest to much into products that may very well be gimmicks.

Many of my technical support sessions are spent teaching users to properly tension and adjust their machines to sew well – without the assistance of various third-party products. Many of these may help – but mainly because they compensate for a machine that is not properly adjusted.  If you are having issues, consult your technician, dealership or the manufacture – and you may save yourself a few dollars and lot of frustration.