Here is a video about calibrating the Ruby 76. Yes, I know it is not the 90. Husqvarna Viking Designer Diamond 76 Calibrating the Embroidery Hoop - YouTube Well, the only thing you learned there is calibration was supposed to be automatic. Moving right along...
Make sure the embroidery module is seated, i. e. attached to the machine properly. Check that the fabric is tightly hooped and that the inner hoop matches the outer hoop.
There are plastic gears driving the unit that may break yielding a grinding sound. Fine wires in the unit may also break, rendering in inoperative. Such repairs call for a serviceman. No seeing the machine, it is difficult to know what the exact problem is.
I suppose you have used the user's guide built into the machine. It offers detailed instructions on calibration. My Sewnet offers a support link near the bottom of its page. The dealer locator is supplied for your convenience. My apologies for not being of more assistance. I am uncertain of the problem.
The User's Guide on the Husqvarna Viking Designer Ruby 90 - YouTube
Dealer Locator ' mySewnet
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.
You can find Adler Manuals on following links. I am sorry I could not find 310 Model. But most of the time, companies make one manual for many models. I hope you can find a manual matching to your machine.
D?rkopp Adler sewing machine manualsUseful Manuals (bootmaker.com)
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.
I am not familiar with this particular machine, but I found references to the thread cutter. Did you try turning it off? Could the cotton thread be rotten, have you tried sewing with button thread?
Thread Trimming Function correlates with the scissors icon on the face of the machine. The G210 in unique in the fact that it has this function, which will automatically trim the thread for you, leaving virtually no mess! This one is a life saver as it relives you from having to spend time cutting and cleaning loose threads!
The text above was from here
https://www.instructables.com/Juki-Sewing-Machine-1/
More here
https://www.google.com/search?q=Juki+HZL+G210+trimming+thread+while+sewing
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