I was having that problem until I found out I had inadvertantly put my rotary cutter back together in the wrong order <wave> just in case: the blade goes between the handle and the black thingy bobber ... and the blades come two to a pack - - you may have put both into your cutter - - I have read a number of quilters warning of this phenomenon ... once I got the cutter put back together correctly, I have become concerned that I will never have to use another blade! <wave>