Serger Class

You might remember waaaaaay back in December, I got a gently-used serger--a Bernina 2000DCE. Well, I finally was able to make it to a Serger 101 class to learn how to use this beauty! Above, you'll see my serger, all threaded and ready to go. Below, are my test swatches. I am now able to successfully sew a 3-thread overlock, 3-thread rolled hem, and 3-thread flat lock. Unfortunately, it looks like I won't be able to do any 4-thread stitches, unless I take the machine in to be looked at. I think that's ok though--- from what I've read on other people's blogs the 3-thread overlock is the stitch most commonly used.

We practiced on cotton muslin and some pretty stable knits. On my own, I tried serging some of my really stretchy knits, and had some trouble. At the end of each piece, it wants to bunch funny and I miss stitching on the last bit of the fabric. Any tips on serging super-stretchy knits? Also, any tips on keeping the seam allowance even as you feed the fabric through the machine?