I lost my machine manual and don't know how to thread it

Since we don't know what machine you have, we're really limited on suggestions. The owner's manual should have instructions for tension setting. If you don't have a manual, search for:
Make Model manual

Assuming it is the top thread that is breaking. Breaking thread usually indicates either the machine is misthreaded or the tension is set too high. However, there are other symptoms that indicate other issues, ie if the thread is shredding or fraying, possibly the incorrect needle is being used or there is a snag/burr somewhere in the thread path. If the machine sews for approximately 2 inches and then breaks, something is catching the thread causing it to stretch until it breaks. Frequently, my thread slips off the thread spool and wraps around the spool pin and breaks.

AVOID old or bargain bin thread.

Remove the top thread from the machine.
Install a brand new needle.
ALWAYS RAISE the presser foot and rethread from the beginning.
Verify the thread path is correct.
Set the top tension to the midway point and retest the machine.

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How to Thread Janome Sewing Machine


http://janome.com/siteassets/support/manuals/economy-models/inst-book-7318-english.pdf

Try this link: http://www.singerco.com/accessories/instruction-manuals Type model no. in the search field and press Search. You'll be able to choose to pay or download for free! Good luck!

Go to the singer website
Go to the home page
At the bottom of the page look for instruction manual--click on it
It will take you to another page
In the box put the model number (example 1934D ) & click search
They usually have a free download

Hi I have bought a Toyota sl3304 overlocker. Unfortunately the manual is missing!!!! Can anyone help please.
Wendy

I found this site that has diagrams for threading the machine. Most Singers thread the same, so once you learn one, you've pretty much got them all.

http://www.sewusa.com/Sewing_Machine_Threading_Diagrams.htm

The bobbin thread usually goes counter-clockwise. If you find that the thread is getting caught up in the bobbin area, check to see if the bobbin has been inserted correctly.

i need information on threading a 920D brothers serger, on paper so i can take it to my machine to thread

Here is a diagram:

http://www.sewusa.com/Threading_Diagrams/Threading_Pages/Brother_Sewing_Machine_Threading/brother_LS_1217_threading_diagram.htm

You can download the manual from the link below: http://www.simplicityhomecare.com/manuals/ There is a quick start guide & full manual. Please update the question & let us know if the information given was useful to you - Good Luck!