u need a silicon based nylon thread and a larger needle. needle may be getting hot too depending on thickness of work. spray some silicon on upper thread.
Go back to basics. Sometimes it's something obvious you've simply missed when setting up the machine.
First check the bobbin is inserted correctly.
Next check the needle is fitted correctly. Some needle shafts are shaped and need to be fitted a specific way around. Have you tried a new needle as a bent or blunt needle can cause issues as well.
Recheck how the machine is threaded as this can affect how a needle moves.
Lovely machine, sounds like it may need some age related maintenance. Start by oiling all the red dots. If you are not familiar with the oiling spots internally, I’d suggest checking out Facebook group vintage Bernina sewing machines, the group has files including manuals and service manuals. There is about 14 points to lubricate these. Good quality sewing machine oil, not household or 3-in-1.
Question edited for typos and add the magic word.
Question moved from Computers to Sewing Machines category.
Hi Joy
All questions need 'make model (what it is)' as first 3 words please
Generic information and videos below, but the answer in general terms is yes you can. Nearly all of the manuals are available online.
https://www.google.com/search?q=How+to+make+sentences+on+embroidery+sewing+machine
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