I cannot thank you enough for posting this. I was in nearly in tears when my embroidery machine started doing this. I used the bobbin case from another machine and the problem was solved. I bought two from amazon.

A very helpful video that clearly shows the effect of such tiny details in the bobbin case. Definitely going to carefully going to pay close attention to this with my machines.

OMG thank you soooo very much. I am new, bought a new machine, and well , mistakes were made. My machine that I wanted to love started doing this. After awhile I was just about to give away my new machine out of frustration but in my heart I still was blaming myself so I started searching. Your video popped up this morning and I just knew. I am ordering the part this morning. Definitely a user error that turned into a mess. 😂

Ive had this issue for 2 days now. Thank you!! Great info. Suggestion: Editing is your friend.😊 Thanks again

This actually helped me, but instead of buying a new piece, I just smoothed it out. I figured if I was gonna have to buy a new piece might as well just try it.

if you’re in need of a quick fix, superglue any holes and slits, leave for half hour or so and then file smooth down with a multi sided nail file/ emery board. If you can run a pair of tights over it without snagging you’re good to go. If you have a needle strike or break it’s one of the first things to check.

This is incredibly helpful, as I'm just getting started with my Mom's old sewing machine and it is having this problem. I'm going to check this out now. Btw you seem really humble and down to earth, and I'm glad I liked this video. Thanks!

I want tell you thank you for your insights. For two weeks I have tried everything to stop the excessive thread build up along my seams, no repair shop is close, your suggestions were applied and now my machine is sewing great again. The one thing I did differently was a very thin layer of clear nail polish applied to any filed areas.

Thank you for the suggestion! I think the piece you were struggling with is to hold down the bobbin case so it doesn't vibrate so much when you sew. I had a bear of a time unscrewing mine for the first time from my Singer because the factory had it screwed in so tight.

Omg! Thank you for this video, my sewing machine started doing this last night and making the same sound yours was making. I FREAKED OUT! being so close to Christmas and projects up to my eyeballs, i had no clue what i would do. I am never able to find anything online that relates to my issue(s) for my singer patchwork machine. It's so frustrating 😢. I am going to try this remedy and hoping it corrects my problem. I am new to the sewing machine and have done pretty well so far....until this happened.... . Thank you again!! 😊

Thank you. I've been having this problem with my Brother SE630.

Serger tweezers help immensely with working inside the machine

Thank you for the video, I appreciate it.

Great video thank female engineer you go girl🎉🎉🎉🎉

Thank you Thank you! This is a big help!!

thank you for this video!

Bobbin cases are easily damaged. Now I have a spare, bought from Amazon.

I feel your pain l have the same problem. I am going to use your method.

Can I buy you and the mechanic a coffee? What is the mechanic's youtube channel? I want to pay him for the consulting.

Helped me to understand. Thank you

Good video. Doesn’t seem to be my issue tho. Back to the drawing board I have no idea why this keeps happening! So Anoying

What kind of screwdriver were you using?

If I had to sew on that machine I would loose interest in sewing real soon. A singer 401A is the newest I'll use.No plastic bobbin cases ever.