Hand wheel is siezing up on sewing machine

Initially, the "safety device has been activated" error is usually caused by a jammed thread or fabric.
2 possible causes
The upper thread has become tangled around the bobbin case,
The needle is bent and hitting the needle plate, so the machine stops.
To fix this error.
1, Unplug your machine,
2. Remove the needle ( I know it is in a down position and locked up) but you can be able to remove it.
3. After removing the needle, turn your hand wheel if still locked up or stiff. Remove your needle plate and remove all your threads both upper and lower.
4. Clean your bobbin area using a brush take a deep breath then blow.
5. After that, try to turn your hand wheel again, if the hand wheel moves freely, rethread your machine and replace your needle with a new one. Then try to sew a few stitches using a hand wheel (do not sew using a pedal) if the hand wheel creates stitches that is the time to sew using the pedal.
If the problem is still there, you possibly have broken gear that needs to be replaced

Could very well be seizing due to lack of oil or buildup of lint, etc. Sergers generally require frequent oiling with fresh good quality oil (consult the manual). Continuing to force the motor to run when the machine is seized can burn up the motor.

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the "hand wheel" on a sewing machine is meant to only advance the mechanism far enough to thread and set the needle , the motor should be used to run the machine else wise , as its turning every thing inside the machine to keep all the functions in "TimE" as models increase in there complexity there hand wheels are harder to move as more stuff needs to be kept in "time" now , also on some models the bobbin winder is directly powered by the hand wheel , if its not in use it should be disengaged completely

Oily Cotton:
1. Remove the bobbin case.
2. Wipe out the oil.
3. Bobbin case rides unto an area that looks like a race track. (Called Race). Wipe out oil.
4. After cleaning oil out take a drop and place unto race.
5. Replace bobbin. (Wipe oil if there is any.)
6. Remove oil from the needle arm. (Goes up and down holding unto the needle.)
7. Replace a small amount of oil on the needle arm.
The sewing the machine should sew very well. It may have some resistance when you turn the hand wheel by hand. Likely, this is due to the machine being new and not being broke in. Otherwise, it would need to be lubricated throughout the machine. Give it while!

before you race the machine into a service centre, most hard to turn problems are from thread and fluff wound around the bobbin shaft in the base of the machine. Use a pin/ needle to remove the thread /fluff then oil the machine using light machine oil. If it is still stiff , take it to a service centre.

Hai, I think your machine timing is changed. So you can't sewing properly. Please check the timing and put the oil everyday all oil parts properly.

Do u regularly oil the parts? It might be stiff when not oiled for a long time and had not been used for a while ;)

Hand wheel "stuck" because you have an obvious jam. Remove bobbin and clean bobbin case, put good quality sewing machine oil on oscillating hook and put new needle in flat side toward back all the way UP, and make sure presser foot UP when you thread machine. Jimmy

since the machine has been setting for 20 years, it needs to be serviced
the old grease & oil have probably turned the gunk. the servicing can also tell if any parts are damaged

hi have you recently refill bobbin seems like you need to reengage clutch tighten inner wheel on hand wheel or slide switch depending on machine refer to your manual good luck
mary h