Drawing up the lower thread

Try a brand new needle. Change thread. Make sure the needle is installed facing the correct direction and is pushed all the way up. The upper tension may be too loose.

Short of that, could be the machine's timing is off.

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Check the spindle the thread is mounted on and see if it\'s wrapped around it. Sometimes thread will catch and wrap around the spool spindle and break.

Check thread guides to be sure there are no nicks that might be catching the thread or damaging it.



Replace the needle.. a burr in the eye can cause upper thread to break. Needles should be replaced often, modern fibres can be hard on them, they get dull and that\'s no help for anything either.



Make sure the thread spool is mounted on the spindle with the thread coming off as directed in the manual. Some machines only work when the thread feeds in the right direction from the spool.



It can also be a tension issue.. tight upper tension or tight bobbin tension. Bobbin tension may be adjustable manually, but it\'s pretty rare for it be a problem. Upper tension, I don\'t know. I\'ve yet to get into computer machines so am not familiar with how they set upper tension.



But the mechanism that produces the tension can wear out or break and need replacement.

Be sure to install a brand new needle.

If the machine is threaded correctly and it still will not pick up the thread, the machine has probably been knocked out of time. Search for sewing machine timing or take it for service.

You should do this by putting very slight pressure on the foot control (or turning the wheel by hand) with the machine's pressure foot up. Then pull the threads by hand to the back of the machine. If the upper thread does not catch the lower thread then the bobbin is not correctly threaded in the bobbin case.

try changing the needle
rethread the machine top & bobbin
check with sewingpartsonline.com-- to see if they show a picture of the bobbins for that machine

make sure to use every thread guide
try a new needle
make sure the bobbin is inserted correctly
if these suggestions don't help & if the machine is still under warrenty take it back & let them check it

You might take a look on ebay item with bernina 700d/800dl instruction manual

my guess is that the lower drive train gears are shot. having the gears replaced would run you about $300

sounds like your keeping the upper thread too tight when you drop your needle down to catch the bobbin or the bobbin thread that you left hang out is too short, let me know if it works amy

Check the needle to be sure it is installed per the manual.

This is usually with the flat side of the shank facing the back of the sewing machine.

Last resort - take the machine in for service as it could be the timing needs to be adjusted.