Have you ever wanted to have perfect thread tension every time you sewed or quilted?  Are you confused with how your bobbin case works or how to calibrate the settings?  Sometimes those tension knobs at the top of your machine are confusing too!  I have been in the same boat, but recently discovered a wonderful trick to help me achieve Perfect Thread Tension no matter what type of thread, fabric or batting that I decide to use!  In this article, I will show you how I thread my Juki J350 Long Arm machine and what I do to get that perfect tension!

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Winding the Bobbin

The Juki Miyabi J-350 QVP uses M sized bobbins (which are larger than domestic machine bobbins).  I typically like to use a 40 wt thread when quilting, but I seem to always have the 50 wt thread in more color variety – so I am using that quite a bit right now.  Here are some basic steps to winding the bobbin on the J-350 QVP.

1. Begin at the thread spool and pull the thread through the thread stand guide.
2. Bring the thread through the Thread Guide Base and then have the thread come back toward the bobbin.
3. manual wind thread around the bobbin several times.
4. Place the bobbin on the Bobbin Winding Shaft and move the Bobbin Presser towards the bobbin.
5. Hold the thread end while the thread winds into the bobbin.
6. When you get enough thread on your bobbin, the Bobbin Presser will fall back.
7. Take off your bobbin and place it in the Bobbin Case.

Calibrating the Bobbin tension

Unlike the top tension of a sewing machine or longarm machine, which requires significant rotational movement to adjust tension, turning the bobbin case screw 1/4 turn in either direction can have a large impact in bobbin tension.   I was recently introduced to a nifty tool to help me calibrate my bobbin tension.   The TOWA Bobbin Tension Gauge associates a numerical value for bobbin tension.  It is easy to dial the bobbin tension in with each new bobbin or when swapping top threads. When I use my TOWA Bobbin Tension Gauge, in my quilting routine, I have saved time and it helps me to start each quilt with proper bobbin tension.  Check out this video to see how easy it is to adjust the bobbin tension.  Also check out this handy day reference chart by Superior Threads!

Threading the Machine Head

I found that threading the head of the Juki J350QVP is just like threading my Juki DU1181N.  This threading is also similar to most sewing machines as well.  Threading the head of the machine is super easy, but in case you are new to threading this type of machine, here are the step by step instructions and a nifty diagram (thanks to my owner’s manual)

Ensuring proper overall tension

Proper needle thread tension is like a game of tug of war.  When both sides are equal neither sides are winning.  When one side is winning and one is losing your tension is off.   The key to finding out which way to turn your tension dial is to find out what side is winning and losing.  Is your top thread loose and bottom too tight?  Or is your top thread tight and your bottom loose?  One way that makes this easy to tell is to use a white piece of fabric to test with two different color threads that will show nicely against one another. The graphic below explains this nicely.  I would actually suggest printing the below picture and keeping it with your sewing machine for a quick reference.  Trust me it will come in handy!

I hope you have found this guide helpful in order to achieve the perfect thread tension for your machine!  Let me know if you have any questions in the comments section and I will be sure to try and help!

Happy Quilting!