Bernina 730 Instruction Manual download pdf (Page 259)

255Embroidery Support – Messages

Titel 1

Trouble Shooting

Prevention and Remedy of Failures

Note the following advice to recognize the causes of most of the operation failures in the

embroidery computer that might occur.

Check First Whether:

• upper and lower threads are threaded correctly

• the needle is inserted correctly - flat part of the

shank to the back

• the needle is the correct size (see Needle/Thread

Chart on pages 17-19)

• the embroidery computer is clean - remove any

thread lint

• the hook race is clean

• bits of thread are trapped between the tension

disks and under the bobbin case spring

Removing Trapped Thread

If the lower thread breaks and the thread is trap-

ped in the area of the take-up lever, proceed as fol-

lows:

•

power switch to «0» (off)

• remove the screw on the head frame with the

angular Torx key

• pull head frame to the left

•

remove remnants of thread

• attach head frame and tighten screw

Upper Thread Breaks

Possible Faults:

•

upper thread tension is too tight

• use of low quality needle. It is best to buy

needles in a BERNINA store

•

needle has been inserted incorrectly. The flat

part of the shank must be to the back

• needle is blunt or bent

• use of poor quality thread, thread with knots,

thread too old or dried out

Possible Solutions:

•

attach foam pad

• use appropriate spool disc

• use net for even unwinding of thread (pull over

upper thread spool)

• stitch plate hole or hook tip is damaged: take

the embroidery computer to an authorized

BERNINA dealer

• reduce embroidery speed

Lower Thread Breaks

• lower thread tension is too tight

• lower thread is trapped in the bobbin case:

•

Replace bobbin

• needle is blunt or bent

• the stitch plate hole has been damaged by the

needle:

• It must be polished by a BERNINA Technician

Skipped Stitches

• incorrect needle used

•

Use only 130/705H needle system

• Needle is bent or blunt

• Needle is not correctly inserted

• Push all the way to the top when inserting

• low quality, badly polished needle used

Needle Breaks

• needle clamp screw is too loose

• defective stitch plate

Unsatisfactory Stitch Formation

• remnants of thread between tension disks:

• pull folded thin fabric (use the fold, not an outer

edge) back and forth between the tension disks

to clean the left and right side of the thread

tension

•

remove any remnants of thread from under the

bobbin case spring

• adjust thread tension

•

used wrong or no stabilizer at all

• incorrectly threaded;

check upper and lower thread

•

when embroidering, thread pigtail tensioner with

lower thread

• use appropriate spool disc

• clean and oil hook (use original oiler only. See

Cleaning and Lubricating on page 185)

Embroidery Computer Fails to Run or Runs

Slowly

• plug not fully inserted

•

power switch in «0» (off) position

• embroidery computer requires normal room tem-

perature for operation

Defective Sewing Light

• take the embroidery computer to an authorized

BERNINA dealer

Lower Thread Indicator Sensor

• bobbin cover is not closed

• not activated in the Setup Program

•

remove any thread lint and remnants

from the bobbin case

Upper Thread Indicator Sensor

• not activated in the Setup Program

032131.70.04_0509_a730_EN

1 2 ... 254 255 256 257 258 259 260 261 262 263 264 ... 284 285

Comments to this Manuals

No comments

Bernina 730 Instruction Manual Page 259

Comments to this Manuals

Related products and manuals for Sewing machines Bernina 730