Did you get the book with both of them, if you did please read the book before you use it.
I bought a new serger with a book, and it said to cut the threads and tie the new threads
to the old thread at the top where your thread goes, and don't forget to cut the thread at
the needle, and then start pulling it through, so the old thread will go through the machine
and bring the new through with it. If you pull the old thread out before you tie it to the new
thread you will have a hard time threading the machine. I made that mistake, and it took me a
long time to get it threaded right. I don't want to make that mistake again. Good Luck, and
you got the good deals I like to get.