Bobbin Wrap - At start up

[baileyuph]

When starting to sew, we hold the threads to prevent bobbin hook wrap.  If the wrap condition tends to be worse, what are the checks?

This condition seems worse with certain threads.

The items checked are:

Both thread tension
Take up tension (upper thread)
Bobbin case opener (vertical axis)
Checked for metal burrs in thread paths (upper and lower)
Hook timing
Feed plate for debris
Belt tension
Pressure foot tension
Bobbin burs

Probably more than this, but is there usually one or two items that contribute most to hook wrapping? 

As a note, when I use cotton threads, it did not seem critical to even hold threads.  Just place material and sew. 

Any wrap experts around?

Doyle

[sofadoc]

Interesting, that you don't have to hold cotton thread.
I don't suppose you got your hands on any "right hand twist" thread have you?

[Grebo]

Is it certain threads or certain materials ?

On a side note  ;)  Sometimes my bobbin /bobbin winder just will not start wrapping right, pulls loose time after time then another time works right first time  ???  Same thread each time. 

[Gregg @ Keystone Sewing]

No hard and fast rules here, but for canvas upholstery work, the threads and materials tend to be heavier, and do not 'catch' on the first stitch, allowing at times the top thread to get jambed down into the hook area.  I don't tell many this, but it's really only the top thread, not the bobbin thread, but I normally will tell people to hold both.

Now, from the garment World, think of dry cleaners, tailors, alteration shops, many seem to be able to get away without holding the threads, and the seem to work out fine.  The stitches with fine threads and materials seem to hold fine, or enough that you don't have to, but should anyway, hold the threads. 

Of course this applies to lock stitch, or any machine that uses a bobbin.

[gene]

I use a mono thread on a juki wannna be machine and I never hold the threads. Did at first because I was told to, but would forget to and realized that I didn't need to. It must be able to catch that first stitch.

gene

[bobbin]

I generally hold the thread when I'm at work (Juki 1508, Consew 255RB, Juki 241), but here at home I never bother to hold the threads on my 1541.  But, it's a horizontal axis bobbin and it's a full function machine. 

Is the dreaded bobbin wrap more prevalent in vertical axis machines?  I've never really thought about it before.  Good question, Doyle. 

[baileyuph]

The things all you people say, I do agree with.  The thread and the things being sewn seem to be associated with "wrapping".  In concert with your comments, when I use 24/4 cotton thread, I never have to hold a thread. 

The right and left twist idea, however is worth pursuing, but how do you check?  Is it stated on the spool?

Is it more prevalent for a vertical axis?  Very possible.  I do have both machines and could be encouraged to think so.  That isn't a scientific justfication, however.

I would like to pursue this and will when the work load is lighter. 

Doyle

[sofadoc]

The right and left twist idea, however is worth pursuing, but how do you check?  Is it stated on the spool?

Cut off a 6" piece of thread.
Hold one end of thread in left hand.
In right hand, hold the other end between thumb and index finger.
Twist toward you (with right hand).
If thread gets tighter, it's left hand twist. If it gets looser, it's right hand twist.

Thinking more about it though, I don't know if that will cause bobbin wrap. What using right hand twist thread usually leads to, is the hook catching between the strands, and breaking the thread.