A tangle of yarn

I spent the last week unpicking a gorgeous angora jersey. Out of date pattern wise. I used the winder my Dad made me and put them into bundles tied nicely, as taught by my mother. I have done this many times with no problem. But this time when I washed them they all tangled together. How do they do that? There were no ends to tangle together. Very bizzare. Today I took my overlocker and sewing machine to be tension fixed, blades sharpened etc and I had been wondering what I was going to do without a sewing machine. Now I know what I am going to be doing, sigh!!