I've just posted the first of several articles related to getting the most accurate results from your rotary cutting and machine piecing.

This forum post is available for you to use to ask questions of me. I'm more than happy to answer your queries, so here you go, here's your space. I'm at your service

What do you mean by "dog legs?"
How does folding the fabric into 4 layers increase your accuracy? When I do this, I get a distortion in the middle. Is that the "dog leg?"

Yes, CDM that's the dog leg. When you fold the fabric into four, it is essential that you make sure the fold at the top (which has four layers) is felt with your finger tips as ONE FOLD. If you feel more that one fold, it means the fabric is not sitting exactly on it's straight of grain, and you'll get the "dog leg" thing happening. Let me know if you need more info CDM, I'm happy to take any questions. Cheerio for now, Judie B