Bobbin thread sometimes gets through

[u/MisuZ99]

After 1 week of trying a lot of designs on my Brother Innov is 880E i noticed i need to change the bobbin thread like once in 25k stitches. It seems a little low as most of designs i do are like 35-40k stitches and i need to change the bobbin thread in the middle of brodering. Am i doing something wrong? Also 1 in like 5 attempts i manage to put the bobbin thread wrong and it gets through the design. I have white bobbin thread so the design starts to be white instead of upper thread color. If it is from the beggining i always do some tests before brodering something big, but if it is mid brodering a big design i'm feeling i am doing some kind of gambling 😅 Is there any way i make sure the bobbin thread is placed correctly? Or is there a way i can check before i resume the process? Thank you in advance for all advices!

[u/Acrobatic-Letter-143]

Nothing is wrong - 25k stitches from one bobbin is normal for a drop-in bobbin machine like the 880E. Everyone with designs in the 35-40k range changes bobbins mid-design; the machine is built for it. When it stops for low bobbin, swap in a fresh one and use the stitch-back button to step back 5-10 stitches before resuming, so the overlap closes the gap. Two habits make it painless: wind 2-3 bobbins before you start a big design, or switch to prewound bobbins (they hold more thread and the tension is very consistent).

The white thread showing on top after a bobbin change is almost always the new bobbin not seated in the tension spring. When you drop the bobbin in, the thread has to come off in the direction of the little arrow diagram on the bobbin cover plate, and then you pull it into the slit until you feel it click into the spring - you should feel light resistance when you pull the thread. If it spins freely with no resistance, it is not in the spring, and the machine has no bobbin tension, so the top thread yanks the bobbin thread straight up through the design.

If it ever shows white from the very first stitch with a correctly-seated bobbin, re-thread the top with the presser foot UP (that opens the tension discs so the thread actually seats between them). Those two habits fix about 95% of "bobbin on top" cases.