I don't know if it is the same kind of problem as "I can't draw a straight line using a ruler"....and I swear, I really can't, or just because I am left handed, but I cannot cut with the rotary cutter. I am messing up fabric, and I have been practicing on scraps, too. I use my clear plastic ruler, my heavy duty wooden ruler, try religiously to follow the lines in my cutting mat...all useless. I really need to be able to cut straight with it, and not look like I was on a roaring drunk before I picked it up.

I hate to have to take my fabric to the LQS and ask them to cut strips for the quilt I am trying to make for my cousin. Not that I won't if I have to, mind you, because I really love that cousin, but I need to be able to do it myself. HELP!!!

Have you tried a left handed rotary cutter?

http://www.amazon.com/Gingher-01-002.../dp/B0026IPASQ

Did you reverse the cutter blade? They come packaged for us righties. You need to change the blade's location to the side that works best for you.

BTW, the ruler "draws" the straight line.

Most cutters can be reversed! Just change the blade location.

One idea is to get one of the cutting systems that are out there. Another would be to get some private lessons at your LQS on cutting. Have someone watch you cut and maybe they can diagnose where the problem is. If the ruler is moving on you, there are grippers to hold it in place.

Are your cuts in a straight line but not perpendicular to the edge of the fabric or are they just generally weaving?

I am left handed and I only had a problem of which side to cut. Make sure you are presses down hard enough.
Just practice and you will get the hang of it. Are you changing your blades?

I don't think it is because you are left handed, I have the same problem but was thinking it is something wrong with me. It looks straight until I cut it and then it looks like I was drunk or something I hold my ruler there and everything but still comes out crazy.

Grannie Annie is right - make sure your blade is on the right side. You want the line up to be: Your hand, the rotary cutter, the blade, then the ruler. And make sure you have a sharp blade in it.

I am left handed, but I don't think that's the problem. I have trouble cutting a straight line with a regular ruler. The June Tailor Shape cutter with the slots has been a strip saver for me. I think my problem is that my hands are very strong and I don't hold the cutter against the ruler well enough. Shape Cutter, here I come.

I am left handed and I can use a rotary cutter without problems. Be sure to keep your cutter snug against your clear ruler.