Necchi royal series

1. Check the thread tension: Make sure the upper thread tension is set correctly for the type of fabric and thread you are using. If the tension is too tight, it can cause the thread to break.
2. Check the thread path: Make sure the thread is correctly threaded through the machine and there are no tangles or knots in the thread path.
3. Check the bobbin tension: Make sure the bobbin tension is set correctly. If the bobbin tension is too tight or too loose, it can cause thread breakage.
4. Use the correct needle: Make sure you are using the correct size and type of needle for the fabric and thread you are using. Using a damaged or bent needle can also cause thread breakage.
5. Slow down your stitching speed: If you are stitching too quickly, it can cause the thread to break. Try reducing your stitching speed to see if this helps.
6. Use high-quality thread: Make sure you are using high-quality thread that is suitable for your project. Poor-quality thread can be more prone to breakage.

thread is not between tension plates but behind one

make sure tat the thread is between the tension plates and not behind and jamming on the bolt
proper tension is a slight resistance when you pull the thread to thread the needle

Have you tried loosening the upper tension? Remove the upper thread, RAISE the presser foot and rethread from the beginning (make sure it follows the correct thread pathway). Sometimes the upper thread jumps out of a thread guide or wraps around something. Or try a different brand of thread? Avoid old or bargain bin threads--use good quality thread. Could also be the incorrect needle for the thread/fabric, ie thread too large for the needle eye.

Sewing Machine Thread Keeps Breaking

NMSU Checklist of Common Machine Troubles

Why Does My Thread Keep Breaking While Sew

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Search the internet for:
Manufacturer + Model + the word "Manual"

or search YouTube videos for "sewing machine threading." You may not find your exact machine, but many machines have similar threading patterns. Be sure to raise the presser foot before threading the upper thread so it will seat properly in the tension disk.

If the thread is breaking at the needle, it could be several problems:
Threaded incorrectly--#1 cause
Upper tension too tight
Install a brand new needle compatible with the fabric & thread
Make sure the thread is not too large for the needle eye
Avoid old, fuzzy, bargain bin thread

All About Needles

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loops under fabric means top tension needs to be tightened
try cleaning the top tension dial with some unwaxed dental floss and see if that helps. if it doesn't then the tension dial may need to be replaced
also check to make sure the spool of thread is not getting caught on the spool holder
also try a new needle--one that is correct for the fabric being sewed

I also own 2 necchi sewing machines, my mechanical is a 4595,,
lower thread tension
to test the bobbin tension, remove the bobbin case & bobbin & hold it by suspending it byb the thread, **** it once or twice, if the tension is correct, the thread will unwind by about an inch or two.
if the tension is too tight, it does not unwind at all, if the tension is too loose, it will drop too much.
to adjust the tension,, left is loosen & to the right tighten

thread breaks
rethread the machine making sure to get all thread guides
top thread tension usually 3 or 4
replace needle- make sure the needle is inserted correctly
some needles don't work with some thread, here's a tip

Cut 6-8 inch piece of thread of the spool you are going to use for your project
Take the needle you are going to use for the project
& insert the thread thru the eye of the needle
& lift one end of the thread to a 45 degree angle
& if the needle is the right size for the thread it will slide down the thread
But if the needle hangs on the thread you need one size larger needle for the thread

try some of these solutions
check your upper thread tension number & see what it's on
the higher the number the tighter the tension
the lower the number the looser the tension
try rethreading the machine
check to make sure you have the right size needle for the fabric
check to make sure your needle is inserted in the needle clamp correctly(the flat side toward the back)
check to see if the needle is bent-roll it on a flat surface to see if it rolls correctly
if it's blunt-it makes a popping sound when going into the fabric

Hi! I found your manual at http://www.sewusa.com/Sewing_Machine_Manuals/Necchi_Manuals/4795_Instruction_Manual.htm

Happy Sewing!

Robbie