Troubleshooting; Thread Breaks - Brother BES-100E Workbook

Thread breaks

Cause
Incorrect position of hook
retaining finger
Holding loose end of
thread during start-up
Thread color
Excessive friction
Bruised cone
Using tape to tie off loose
thread ends
Old, dry thread
Too tight or inconsistent
twist on the thread
Lint build-up in tension
discs, throat plate or bob-
bin case
Build-up of thread behind
hook
Incorrect needle depth
Improper timing
Trimmer mechanism not
working properly
Needle too close to hole in
throat plate
Too much or incorrect
adhesive spray
Bent needle tip

Troubleshooting

If the hook is set too close to the needle or the retaining finger is bent, the
thread can't pass through. Make adjustment in position or replace bent retaining
finger.
Pulling the thread too tight and either wrapping it around the holding disc or
holding it in your hand causes the needle to bend and the needle and/or thread
to break.
Some colors are more susceptible to thread breaks than others due to the
amount of chemical processing involved. For example, some dark colors require
more or stronger dye solutions, which place increased stress on the thread.
Replace thread.
Increased friction between the needle and thick or abrasive fabrics or backings
can cause the needle to heat up, breaking the thread. This can also happen on
fabric or backings with excessive chemical coatings or treatments. Reduce
machine speed, use a Teflon-coated needle, apply silicone spray to the thread
or re-punch the design with longer stitch lengths.
Bruising occurs when thread cones fall on the floor, causing the lower windings
to loosen and catch as the thread spools off. Pull off the affected portion of the
thread or replace the cone.
Tape leaves a residue that causes friction and breaks. Pull off the affected por-
tion and don't use tape.
Replace thread. Thread becomes brittle with age and prolonged exposure to
light, air, and heat. Store new thread in a cool, dark place.
Replace cone of thread.
Clean these areas with canned air or a brush.
Using a brush or tweezers, remove thread build-up on the hook shaft. In severe
cases, the build-up may push the hook out of alignment and affect timing. If this
happens, remove the hook, clean the area and reset the timing.
Commonly occurring after hitting the hoop or throat plate, this problem shows
up when the thread splits and one ply continues to sew while the other peels
back. The thread eventually breaks, leaving previous stitching thinned out.
Reset needle depth, and possibly timing, according to machine instructions.
Also check for needle damage.
This causes many problems, such as broken needles, poor stitching (or no
stitching) in addition to thread breaks.
Thread ends may not be cut cleanly or thread ends may be cut too short, acti-
vating your machine's thread break detectors. Adjust trimmers
This causes thread to fray and eventually break. Adjust throat plate and/or nee-
dle position.
Use only spray adhesives designed for embroidery applications—and use spar-
ingly! Excess adhesive build-up on needles causes them to drag and break
threads. Replace the needle and examine your adhesive application technique.
Usually happens after the needle hits an impenetrable object (hoop, throat
plate, hook). Replace the needle. (Also check the hook for burrs and the timing
after hitting a hard object.)
Action
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