No bobbin tension

The tension depends on what you are sewing but usually a 4 -5. Also make sure thread and needle are the correct size for the materials you are sewing. and make sure needle and bobbin are threaded correctly and that needle is not, blunt or bent. :)

The hook timing is out. If it's very new I'm assuming it's still under warranty. Take it to the place you purchased for repair.

Assuming your top thread tension at no.4 or mid range, still not good, check your bobbin thread tension ok or not. If tight try reduce the tension. Problem persist, possibly bobbin case tension spring dirty or ageing.

have you tried to tighten the bobbin tension spring??

if you have verified the needle is the right one for the machine model and in correctly (long groove the correct direction), that the bobbin is wound and in the case correctly, try a different material and/or thread. If the problem persists, take the machine to a better mechanic/shop. It sounds like it is out of sync. (hook rotation to needle throw).

check tension usually 3 or 4 is good
clean under needle plate where feed dogs are for lint
is the flat side of the needle toward the back of the machine
rethread machine
is needle the right one for the fabric & thread
it might also need to be serviced

Sounds like you need to retime the machine, if you email me I can attach instructions [email protected]

sounds like it needs a service call. if you do not have a sewing repair man you use regularly to clean machine the local fabric store should know who you could call.

It is most likely because you have it on a type of stitch but did not switch the didstance that you want the zig zag to be. Just change you stitch or your distance.

If the looping is happening on the underside, it is your top tension that is to blame, conversely looping on top is bobbin tension.........take a look HERE for detail on cleaning lint buildup.

Top tension should be set around the middle of the range, usually 4 - 6.

I would not advise playing with bobbin tensions, however, you can take the needle plate off to clean the hook race area (where bobbin case sits) ...this is good housekeeping, my wife does this every time she replaces the bobbin....just take it out and clean the bobbin case and the fixed metal hook race with a small brush to remove lint, if there appears to be fine dirty deposits, a cloth or cotton bud (Q tip) moistened (not soaked) with methylated spirit will do the trick.

Bargainbox